FuelCell Energy (FCEL) 10-K 27 Dec 24 2024 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Oct. 31, 2024	Dec. 23, 2024	Apr. 30, 2024
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Oct. 31, 2024
Document Transition Report	false
Entity File Number	1-14204
Entity Registrant Name	FUELCELL ENERGY, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	06-0853042
Entity Address, Address Line One	3 Great Pasture Road
Entity Address, City or Town	Danbury
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06810
City Area Code	203
Local Phone Number	825-6000
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	FCEL
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
ICFR Auditor Attestation Flag	true
Entity Public Float			$ 424,996,599
Entity Common Stock, Shares Outstanding		20,449,715
Auditor Name	KPMG LLP
Auditor Firm ID	185
Auditor Location	Philadelphia, Pennsylvania
Entity Central Index Key	0000886128
Amendment Flag	false
Current Fiscal Year End Date	--10-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Current assets:
Cash and cash equivalents, unrestricted	$ 148,133	$ 249,952
Restricted cash and cash equivalents - short-term	12,161	5,159
Investments - short-term	109,123	103,760
Accounts receivable, net	11,751	3,809
Unbilled receivables	36,851	16,296
Inventories	113,703	84,456
Other current assets	12,736	12,881
Total current assets	444,458	476,313
Restricted cash and cash equivalents - long-term	48,589	44,465
Inventories - long-term	2,743	7,329
Project assets, net	242,131	258,066
Property, plant and equipment, net	130,686	89,668
Operating lease right-of-use assets, net	8,122	8,352
Goodwill	4,075	4,075
Intangible assets, net	14,779	16,076
Other assets	48,541	51,176
Total assets (1)	944,124	955,520
Current liabilities:
Current portion of long-term debt	15,924	10,067
Current portion of operating lease liabilities	807	599
Accounts payable	22,585	26,518
Accrued liabilities	30,362	26,313
Deferred revenue	4,226	2,406
Total current liabilities	73,904	65,903
Long-term deferred revenue	3,010	732
Long-term operating lease liabilities	8,894	8,992
Long-term debt and other liabilities	130,850	119,588
Total liabilities (1)	216,658	195,215
Redeemable Series B preferred stock (liquidation preference of $64,020 as of October 31, 2024 and October 31, 2023)	59,857	59,857
Stockholders' equity:
Common stock ($0.0001 par value); 1,000,000,000 shares authorized as of October 31, 2024 and October 31, 2023; 20,375,932 and 15,020,872 shares issued and outstanding as of October 31, 2024 and October 31, 2023, respectively	2	2
Additional paid-in capital	2,300,031	2,199,704
Accumulated deficit	(1,641,550)	(1,515,541)
Accumulated other comprehensive loss	(1,561)	(1,672)
Treasury stock, Common, at cost (12,543 and 8,216 shares as of October 31, 2024 and October 31, 2023, respectively)	(1,198)	(1,078)
Deferred compensation	1,198	1,078
Total stockholders' equity	656,922	682,493
Noncontrolling interests	10,687	17,955
Total equity	667,609	700,448
Total liabilities, redeemable Series B preferred stock and total equity	$ 944,124	$ 955,520

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	20,375,932	15,020,872
Common stock, shares outstanding (in shares)	20,375,932	15,020,872
Treasury stock, common shares (in shares)	12,543	8,216
Assets	$ 944,124	$ 955,520
Cash	148,133	249,952
Accounts receivable, net	11,751	3,809
Unbilled receivables	36,851	16,296
Operating lease right-of-use assets, net	8,122	8,352
Other current assets	12,736	12,881
Restricted cash and cash equivalents - long-term	48,589	44,465
Project assets, net	242,131	258,066
Derivative asset	1,200	4,100
Other assets	48,541	51,176
Current portion of operating lease liabilities	807	599
Accounts payable	22,585	26,518
Long-term operating lease liabilities	8,894	8,992
Deferred revenue	4,226	2,406
Derivative liabilities	4,000	0
Accrued liabilities	30,362	26,313
Other non-current liabilities	130,850	119,588
Variable interest entity ("VIE")
Assets	311,723	235,290
Cash	2,891	4,797
Accounts receivable, net	674
Unbilled receivables	9,479	1,876
Operating lease right-of-use assets, net	1,663	1,680
Other current assets	135,756	50,713
Restricted cash and cash equivalents - long-term	639	526
Project assets, net	157,604	170,444
Derivative asset		$ 4,127
Derivative Asset, Noncurrent, Statement of Financial Position [Extensible Enumeration]		Other assets
Other assets	3,018	$ 1,125
Current portion of operating lease liabilities	204	203
Accounts payable	181,274	165,824
Long-term operating lease liabilities	2,142	2,159
Deferred revenue	20
Derivative liabilities	3,693
Accrued liabilities	341
Other non-current liabilities	240	187
Series B Preferred Stock
Preferred stock, liquidation preference value	$ 64,020	$ 64,020

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Revenues:
Total revenues	$ 112,132	$ 123,394	$ 130,484
Costs of revenues:
Total costs of revenues	148,050	133,929	160,059
Gross loss	(35,918)	(10,535)	(29,575)
Operating expenses:
Administrative and selling expenses	64,604	64,528	79,620
Research and development expenses	55,404	61,021	34,529
Restructuring expense	2,562
Total costs and expenses	122,570	125,549	114,149
Loss from operations	(158,488)	(136,084)	(143,724)
Interest expense	(9,690)	(7,247)	(6,394)
Interest income	13,720	15,795	3,386
Gain on extinguishment of finance obligations and debt, net		15,337
Other (expense) income, net	(2,295)	4,724	319
Loss before provision for income taxes	(156,753)	(107,475)	(146,413)
Provision for income taxes	(25)	(581)	(819)
Net loss	(156,778)	(108,056)	(147,232)
Net loss attributable to noncontrolling interests	(30,769)	(488)	(4,510)
Net loss attributable to FuelCell Energy, Inc.	(126,009)	(107,568)	(142,722)
Series B preferred stock dividends	(3,200)	(3,200)	(3,200)
Net loss attributable to common stockholders	$ (129,209)	$ (110,768)	$ (145,922)
Loss per share basic and diluted:
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (7.83)	$ (7.92)	$ (11.43)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (7.83)	$ (7.92)	$ (11.43)
Basic weighted average shares outstanding (in shares)	16,505,257	13,991,593	12,771,305
Diluted weighted average shares outstanding (in shares)	16,505,257	13,991,593	12,771,305
Net loss	$ (156,778)	$ (108,056)	$ (147,232)
Other comprehensive loss:
Foreign currency translation adjustments	111	80	(933)
Total comprehensive loss	(156,667)	(107,976)	(148,165)
Comprehensive loss attributable to noncontrolling interests	(30,769)	(488)	(4,510)
Comprehensive loss attributable to FuelCell Energy, Inc.	(125,898)	(107,488)	(143,655)
Product
Revenues:
Total revenues	25,675	19,589	60,000
Costs of revenues:
Total costs of revenues	39,582	12,878	64,495
Service
Revenues:
Total revenues	9,969	49,084	12,786
Costs of revenues:
Total costs of revenues	11,098	44,953	17,233
Generation
Revenues:
Total revenues	49,975	37,508	36,186
Costs of revenues:
Total costs of revenues	79,861	62,913	63,147
Advanced Technologies
Revenues:
Total revenues	26,513	17,213	21,512
Costs of revenues:
Total costs of revenues	$ 17,509	$ 13,185	$ 15,184

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total Stockholder's Equity	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss	Treasury Stock	Deferred Compensation	Noncontrolling Interests	Total
Beginning Balance at Oct. 31, 2021	$ 642,438	$ 1	$ 1,908,507	$ (1,265,251)	$ (819)	$ (586)	$ 586		$ 642,438
Beginning Balance at (in shares) at Oct. 31, 2021		12,220,600
Sale of common stock, net of fees	183,552		183,552						183,552
Sale of common stock, net of fees (in shares)		1,279,897
Common stock issued, non-employee compensation	305		305						$ 305
Common stock issued, non-employee compensation (in shares)		2,562							2,562
Stock issued under benefit plans, net of taxes paid upon vesting of restricted stock awards	(1,840)		(1,840)						$ (1,840)
Stock issued under benefit plans, net of taxes paid upon vesting of restricted stock awards (in shares)		17,998
Share based compensation	6,792		6,792						6,792
Preferred dividends - Series B	(3,200)		(3,200)						(3,200)
Effect of foreign currency translation	(933)				(933)				(933)
Adjustment for deferred compensation						(269)	269
Adjustment for deferred compensation (in shares)		(2,314)
Reclassification of redeemable non-controlling interest								$ 12,419	12,419
Return of capital to noncontrolling interest								(496)	(496)
Distribution to non-controlling interest								(308)	(308)
Net Loss	(142,722)			(142,722)				(4,510)	(147,232)
Ending Balance at Oct. 31, 2022	684,392	$ 1	2,094,116	(1,407,973)	(1,752)	(855)	855	7,105	691,497
Ending Balance at (in shares) at Oct. 31, 2022		13,518,743
Sale of common stock, net of fees	97,439	$ 1	97,438						97,439
Sale of common stock, net of fees (in shares)		1,477,361
Common stock issued, non-employee compensation	225		225						$ 225
Common stock issued, non-employee compensation (in shares)		3,454							3,454
Stock issued under benefit plans, net of taxes paid upon vesting of restricted stock awards	(829)		(829)						$ (829)
Stock issued under benefit plans, net of taxes paid upon vesting of restricted stock awards (in shares)		24,768
Share based compensation	11,954		11,954						11,954
Preferred dividends - Series B	(3,200)		(3,200)						(3,200)
Effect of foreign currency translation	80				80				80
Adjustment for deferred compensation						(223)	223
Adjustment for deferred compensation (in shares)		(3,454)
Contributions received for sale of noncontrolling interest								9,052	9,052
Reclassification of redeemable non-controlling interest								3,030	3,030
Distribution to non-controlling interest								(744)	(744)
Net Loss	(107,568)			(107,568)				(488)	(108,056)
Ending Balance at Oct. 31, 2023	682,493	$ 2	2,199,704	(1,515,541)	(1,672)	(1,078)	1,078	17,955	$ 700,448
Ending Balance at (in shares) at Oct. 31, 2023		15,020,872							15,020,872
Sale of common stock, net of fees	92,555		92,555						$ 92,555
Sale of common stock, net of fees (in shares)		5,302,378
Common stock issued, non-employee compensation	159		159						$ 159
Common stock issued, non-employee compensation (in shares)		6,651							6,651
Stock issued under benefit plans, net of taxes paid upon vesting of restricted stock awards	(951)		(951)						$ (951)
Stock issued under benefit plans, net of taxes paid upon vesting of restricted stock awards (in shares)		50,358
Share based compensation	11,764		11,764						11,764
Preferred dividends - Series B	(3,200)		(3,200)						(3,200)
Effect of foreign currency translation	111				111				111
Adjustment for deferred compensation						(120)	120
Adjustment for deferred compensation (in shares)		(4,327)
Contributions received for sale of noncontrolling interest								25,122	25,122
Distribution to non-controlling interest								(1,621)	(1,621)
Net Loss	(126,009)			(126,009)				(30,769)	(156,778)
Ending Balance at Oct. 31, 2024	$ 656,922	$ 2	$ 2,300,031	$ (1,641,550)	$ (1,561)	$ (1,198)	$ 1,198	$ 10,687	$ 667,609
Ending Balance at (in shares) at Oct. 31, 2024		20,375,932							20,375,932

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Cash flows from operating activities:
Net loss	$ (156,778)	$ (108,056)	$ (147,232)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation	11,764	11,954	6,792
Depreciation and amortization	36,193	25,375	21,274
Gain on extinguishment of finance obligations and debt, net		(15,337)
Non-cash interest expense on finance obligations	2,182	3,228	4,210
Unrealized loss (gain) on derivative contracts	9,940	(7,441)	(779)
Operating lease costs	1,404	1,486	1,521
Operating lease payments	(1,266)	(1,226)	(1,438)
Impairment of property, plant and equipment and project assets	1,264	2,375	1,782
Unrealized foreign currency (gains) losses		(57)	583
Other, net	237	456	2,632
(Increase) decrease in operating assets:
Accounts receivable	(7,942)	1,076	9,199
Unbilled receivables	(23,043)	(21,921)	(231)
Inventories	(29,247)	4,686	(28,058)
Other assets	(5,404)	(13,090)	(2,092)
(Decrease) increase in operating liabilities:
Accounts payable	(999)	3,001	6,332
Accrued liabilities	4,691	(4,461)	24,616
Deferred revenue	4,098	(22,298)	(11,278)
Net cash used in operating activities	(152,906)	(140,250)	(112,167)
Cash flows from investing activities:
Capital expenditures	(47,721)	(39,355)	(21,078)
Project asset expenditures	(11,832)	(53,007)	(25,573)
Maturity of held-to-maturity debt securities	835,240	199,090
Purchases of held-to-maturity debt securities	(835,736)	(299,093)
Net cash used in investing activities	(60,049)	(192,365)	(46,651)
Cash flows from financing activities:
Repayment of debt and finance obligations	(11,699)	(47,830)	(9,544)
Proceeds from the issuance of debt	23,104	100,500
Payment for deferred financing costs	(1,159)	(3,469)
Common stock issued for stock plans and related expenses	120	56	47
Contributions received from sale of noncontrolling interest, net of return of capital	25,122	9,052	11,923
Distribution to noncontrolling interest	(1,621)	(596)	(308)
Payments for taxes related to net share settlement of equity awards	(1,071)	(885)	(1,887)
Common stock issuance, net of fees	92,555	97,439	183,552
Payment of preferred dividends	(3,200)	(3,200)	(3,200)
Net cash provided by financing activities	122,151	151,067	180,583
Effects on cash from changes in foreign currency rates	111	80	(933)
Net (decrease) increase in cash, cash equivalents and restricted cash	(90,693)	(181,468)	20,832
Cash, cash equivalents and restricted cash-beginning of period	299,576	481,044	460,212
Cash, cash equivalents and restricted cash-end of period	$ 208,883	$ 299,576	$ 481,044

Consolidated Statements of Ca_2

Consolidated Statements of Cash Flows (parenthetical) - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022	Oct. 31, 2021
Consolidated Statements of Cash Flows
Cash and cash equivalents, unrestricted	$ 148,133	$ 249,952	$ 458,055
Restricted cash and cash equivalents - short-term	12,161	5,159	4,423
Restricted cash and cash equivalents - long-term	48,589	44,465	18,566
Total cash, cash equivalents and restricted cash	$ 208,883	$ 299,576	$ 481,044	$ 460,212

Nature of Business, Basis of Pr

Nature of Business, Basis of Presentation and Significant Accounting Policies	12 Months Ended
	Oct. 31, 2024
Nature of Business, Basis of Presentation and Significant Accounting Policies
Nature of Business, Basis of Presentation and Significant Accounting Policies	Note 1. Nature of Business, Basis of Presentation and Significant Accounting Policies Nature of Business and Basis of Presentation Headquartered in Danbury, Connecticut, FuelCell Energy, Inc. (together with its subsidiaries, the “Company” “FuelCell Energy,” “we,” “us,” or “our”) is a global leader in delivering environmentally responsible distributed baseload energy platform solutions through our proprietary fuel cell technology. Today, we offer commercial technology that produces clean electricity, heat, clean hydrogen, and water and is also capable of recovering and capturing carbon for utilization and/or sequestration, depending on product configuration and application. We also continue to invest in product development and commercializing technologies that are expected to add new capabilities to our platforms’ abilities to deliver hydrogen and long duration hydrogen-based energy storage through our solid oxide technologies, as well as further enhance our existing platforms’ carbon capture solutions. ​ FuelCell Energy is focused on advancing sustainable clean energy technologies that address some of the world’s most critical challenges around energy access, security, resilience, reliability, affordability, safety and environmental stewardship. As a leading global manufacturer of proprietary fuel cell technology platforms, FuelCell Energy is uniquely positioned to serve customers worldwide with sustainable products and solutions for industrial and commercial businesses, utilities, governments, municipalities, and communities. ​ The consolidated financial statements include our accounts, those of our wholly-owned subsidiaries, and those of our consolidated variable interest entities. All intercompany accounts and transactions have been eliminated. At 5:00 p.m. Eastern Time on November 8, 2024, we effected a 1 Liquidity Our principal sources of cash have been proceeds from the sale of our products and projects, electricity generation revenues, research and development and service agreements with third parties, sales of our common stock through public equity offerings, and proceeds from debt, project financing and tax monetization transactions. We have utilized this cash to accelerate the commercialization of our solid oxide platforms, develop new capabilities to separate and capture carbon, develop and construct project assets, invest in capital improvements and expansion of our operations, perform research and development, pay down existing outstanding indebtedness, and meet our other cash and liquidity needs. As of October 31, 2024, unrestricted cash and cash equivalents totaled $148.1 million compared to $250.0 million as of October 31, 2023. During the years ended October 31, 2024 and 2023, the Company invested in United States (U.S.) Treasury Securities. The amortized cost of the U.S. Treasury Securities outstanding totaled $109.1 million as of October 31, 2024 compared to $103.8 million as of October 31, 2023 and is classified as Investments - short-term on the Consolidated Balance Sheets. The outstanding U.S. Treasury Securities as of October 31, 2024 matured between November 5, 2024 and November 29, 2024. On October 31, 2024, the Company closed on a project debt financing transaction with the Export-Import Bank of the United States (“EXIM”) to support the Company’s obligations under its long-term service agreement with Gyeonggi Green Energy Co., Ltd. (“GGE”), pursuant to which the Company is to supply forty-two 1.4-megawatt upgraded carbonate fuel cell modules to replace existing units at GGE’s Hwaseong Baran Industrial Complex. In conjunction with this financing, the Company entered into a promissory note and related security agreements securing the loan with equipment liens, resulting in net proceeds of approximately $9.2 million. See Note 12. “Debt” for additional information regarding the transaction with EXIM. ​ On April 25, 2024, the Company (through one of its indirect subsidiaries) entered into three related term loan facilities (which are referred to herein as the “Derby Senior Back Leverage Loan Facility” and the “Derby Subordinated Back Leverage Loan Facility”), resulting in net proceeds of $12.8 million. See Note 12. “Debt” for additional information regarding the Derby Senior Back Leverage Loan Facility and the Derby Subordinated Back Leverage Loan Facility. ​ On April 10, 2024, the Company entered into Amendment No. 1 (the “Amendment”) to the Open Market Sale Agreement, dated July 12, 2022 (the “2022 Sales Agreement”), with Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canaccord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC (each, an “Agent” and together, the “Agents”) (the 2022 Sales Agreement as amended by the Amendment, the “Amended Sales Agreement”), with respect to an at the market offering program under which the Company may, from time to time, offer and sell shares of its common stock having an aggregate offering price of up to $300.0 million (exclusive of any amounts previously sold under the 2022 Sales Agreement prior to its amendment). Between April 10, 2024 (the date of the Amended Sales Agreement) and October 31, 2024, approximately 5.3 million shares of the Company’s common stock were sold under the Amended Sales Agreement resulting in gross proceeds of approximately $95.1 million. On December 27, 2024, the Company entered into Amendment No. 2 to the Amended Sales Agreement, which removes certain representations and warranties relating to the Company’s status as a well-known seasoned issuer. See Note 13. “Stockholders’ Equity and Warrant Liabilities” for additional information regarding the 2022 Sales Agreement and the Amended Sales Agreement. ​ During the first quarter of fiscal year 2024, the Company completed its technical improvement plan to bring the Groton Project (defined elsewhere herein) to its rated capacity and the Groton Project reached its design rated output of 7.4 MW. The Company achieved all conditions precedent required for the first annual funding from East West Bancorp, Inc. (“East West Bank”) under the tax equity financing transaction between the Company and East West Bank and, as a result, the Company received a $4.0 million contribution during the year ended October 31, 2024 which is recorded as noncontrolling interest on the Consolidated Balance Sheets. ​ During the fourth quarter of fiscal year 2023, the Company closed on a tax equity financing transaction with Franklin Park 2023 FCE Tax Equity Fund, LLC (“Franklin Park”), a subsidiary of Franklin Park Infrastructure, LLC, for two fuel cell power plant installations -- the 14.0 megawatt (“MW”) Derby Fuel Cell Project and the 2.8 MW SCEF Fuel Cell Project, both located in Derby, Connecticut (collectively, the “Derby Projects”). Franklin Park’s tax equity commitment with respect to the Derby Projects totaled $30.2 million. Of this amount, approximately $9.1 million was received on October 31, 2023 and the remaining approximately $21.1 million was received during the year ended October 31, 2024. In connection with the initial closing of this tax equity financing transaction in fiscal year 2023, the Company paid closing costs of approximately $1.8 million, which included appraisal fees, title insurance expenses and legal and consulting fees. ​ We believe that our unrestricted cash and cash equivalents, expected receipts from our contracted backlog, funds received upon the maturity of U.S. Treasury Securities, and release of short-term restricted cash less expected disbursements over the next twelve months will be sufficient to allow the Company to meet its obligations for at least one year from the date of issuance of these financial statements. ​ To date, we have not achieved profitable operations or sustained positive cash flow from operations. The Company’s future liquidity, for fiscal year 2025 and in the long-term, will depend on its ability to (i) timely complete current projects in process within budget, (ii) increase cash flows from its generation operating portfolio, including by meeting conditions required to timely commence operation of new projects, operating its generation operating portfolio in compliance with minimum performance guarantees and operating its generation operating portfolio in accordance with revenue expectations, (iii) obtain financing for project construction and manufacturing expansion, (iv) obtain permanent financing for its projects once constructed, (v) increase order and contract volumes, which would lead to additional product sales, service agreements and generation revenues, (vi) obtain funding for and receive payment for research and development under current and future Advanced Technologies contracts, (vii) successfully commercialize its solid oxide, hydrogen and carbon capture platforms, (viii) implement capacity expansion for solid oxide product manufacturing, (ix) implement the product cost reductions necessary to achieve profitable operations, (x) manage working capital and the Company’s unrestricted cash balance and (xi) access the capital markets to raise funds through the sale of debt and equity securities, convertible notes, and other equity-linked instruments. We are continually assessing different means by which to accelerate the Company’s growth, enter new markets, commercialize new products, and enable capacity expansion. Therefore, from time to time, the Company may consider and enter into agreements for one or more of the following: negotiated financial transactions, minority investments, collaborative ventures, technology sharing, transfer or other technology license arrangements, joint ventures, partnerships, acquisitions or other business transactions for the purpose(s) of geographic or manufacturing expansion and/or new product or technology development and commercialization, including hydrogen production through our carbonate and solid oxide platforms and storage and carbon capture, sequestration and utilization technologies. Our business model requires substantial outside financing arrangements and satisfaction of the conditions of such arrangements to construct and deploy our projects to facilitate the growth of our business. The Company has invested capital raised from sales of its common stock to build out its project portfolio. The Company has also utilized and expects to continue to utilize a combination of long-term debt and tax equity financing (e.g., sale-leaseback transactions, partnership flip transactions and the monetization and/or transfer of eligible investment and production tax credits) to finance its project asset portfolio as these projects commence commercial operations, particularly in light of the passage of the Inflation Reduction Act in August 2022. The Company may also seek to undertake private placements of debt securities to finance its project asset portfolio. The proceeds of any such financing, if obtained, may allow the Company to reinvest capital back into the business and to fund other projects. We also expect to seek additional financing in both the debt and equity markets in the future. If financing is not available to us on acceptable terms if and when needed, or on terms acceptable to us or our lenders, if we do not satisfy the conditions of our financing arrangements, if we spend more than the financing approved for projects, if project costs exceed an amount that the Company can finance, or if we do not generate sufficient revenues or obtain capital sufficient for our corporate needs, we may be required to further reduce or slow planned spending, further reduce staffing, sell assets, seek alternative financing and take other measures, any of which could have a material adverse effect on our financial condition and operations. ​ Summary of Significant Accounting Policies Cash and Cash Equivalents All cash equivalents consist of investments in money market funds with original maturities of three months or less at the date of acquisition. We place our temporary cash equivalent investments with high credit quality financial institutions. Inventories and Advance Payments to Vendors Inventories consist principally of raw materials and work-in-process. Cost is determined using the first-in, first-out cost method. Included in our inventory balance are used modules that are brought back into inventory upon installation of new modules. When a new module is installed, a determination is made as to whether the used module has remaining useful life or should be scrapped and materials recycled. Modules that are deemed to have remaining useful life are put into inventory at an estimated value based on the expected remaining life of the module and its projected output. In certain circumstances, we will make advance payments to vendors for future inventory deliveries. These advance payments are recorded as Other current assets on the Consolidated Balance Sheets. Inventories are reviewed to determine net realizable value. This review includes analyzing inventory levels of individual parts considering the current design of our products and production requirements as well as the expected inventory requirements for maintenance on installed power platforms. Investments – Short-Term The Company invests in U.S. Treasury Securities which are held-to-maturity and are recorded at amortized cost. Allowance for Doubtful Accounts and Credit Losses The Company had no allowance for doubtful accounts or credit losses as of October 31, 2024 and 2023. Uncollectible accounts receivable are charged against the allowance for doubtful accounts when all collection efforts have failed and it is deemed unlikely that the amount will be recovered. The Company would record a specific reserve for individual accounts when the Company becomes aware of specific customer circumstances such as in the case of a bankruptcy filing or the deterioration in the customer’s operating results or financial position. Project Assets Project assets consist of capitalized costs for fuel cell projects in various stages of development, including those projects with respect to which we have entered into power purchase agreements (“PPAs”) and those projects with respect to which we expect to secure long-term contracts. Such development costs are generally incurred prior to entering into a definitive sales or long-term financing agreement for the project. Project assets also include capitalized costs for fuel cell projects which are the subject of sale-leaseback transactions with Crestmark Equipment Finance, a division of MetaBank (“Crestmark”). Project asset costs include costs for developing and constructing a complete turn-key fuel cell project. Development costs can include legal, consulting, permitting, interconnect, and other similar costs. To the extent we enter into a definitive sales agreement, we expense project assets to cost of sales after the respective project asset is sold to a customer and all revenue recognition criteria have been met. Property, Plant and Equipment Property, plant and equipment are stated at cost, less accumulated depreciation which is recorded based on the straight-line method over the estimated useful lives of the respective assets. Leasehold improvements are amortized on the straight-line method over the shorter of the estimated useful lives of the assets or the term of the lease. When property, plant or equipment is sold or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and any resulting gain or loss is reflected in operations for the period. Goodwill and Indefinite-Lived Intangibles Goodwill represents the excess of the aggregate purchase price over the fair value of the net assets acquired in a business combination and is reviewed for impairment at least annually. The intangible asset represents indefinite-lived in-process research and development (“IPR&D”) for cumulative research and development efforts associated with the development of solid oxide fuel cell stationary power generation and is also reviewed at least annually for impairment. Accounting Standards Codification (“ASC”) Topic 350: Intangibles - Goodwill and Other The Company completed its annual impairment analysis of goodwill and IPR&D as of July 31, 2024. The goodwill and IPR&D asset are both held by the Company’s Versa Power Systems, Inc. (“Versa Inc.”) reporting unit. Goodwill and the IPR&D asset are also reviewed for possible impairment whenever changes in conditions indicate that the fair value of a reporting unit or IPR&D asset is more likely than not below its respective carrying value. No impairment charges were recorded with respect to goodwill or the IPR&D asset during the fiscal years ended October 31, 2024, 2023 and 2022. Impairment of Long-Lived Assets (including Project Assets) Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset group may not be recoverable. If events or changes in circumstances indicate that the carrying amount of the asset group may not be recoverable, we compare the carrying amount of the asset group to the future undiscounted net cash flows, excluding debt service costs, expected to be generated by the asset group and its ultimate disposition. If the sum of the undiscounted cash flows is less than the carrying value, the impairment to be recognized is measured by the amount by which the carrying amount of the asset group exceeds its fair value. Revenue Recognition The Company recognizes revenue in accordance with ASC Topic 606: Revenue from Contracts with Customers A contract is accounted for when there has been approval and commitment from both parties, the rights of the parties are identified, payment terms are identified, the contract has commercial substance and collectability of consideration is probable. Performance obligations under a contract are identified based on the goods or services that will be transferred to the customer that are both capable of being distinct and are distinct in the context of the contract. In certain instances, the Company has concluded distinct goods or services should be accounted for as a single performance obligation that is a series of distinct goods or services that have the same pattern of transfer to the customer. To the extent a contract includes multiple promised goods or services, the Company must apply judgment to determine whether the customer can benefit from the goods or services either on their own or together with other resources that are readily available to the customer (the goods or services are capable of being distinct) and if the promise to transfer the goods or services to the customer is separately identifiable from other promises in the contract (the goods or services are distinct in the context of the contract). If these criteria are not met, the promised goods or services are accounted for as a single performance obligation. The transaction price is determined based on the consideration that the Company will be entitled to in exchange for transferring goods or services to the customer. To the extent the transaction price includes variable consideration, the Company estimates the amount of variable consideration that should be included in the transaction price, generally utilizing the expected value method. Determining the transaction price requires judgment. If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price to each performance obligation based on a relative standalone selling price basis. Standalone selling price is determined by the price at which the performance obligation is sold separately. If the standalone selling price is not observable through past transactions, the Company estimates the standalone selling price by taking into account available information such as market conditions and internally approved pricing guidelines related to the performance obligations. Performance obligations are satisfied either over time or at a point in time as discussed in further detail below. In addition, the Company’s contracts with customers generally do not include significant financing components or non-cash consideration. The Company has elected practical expedients in the accounting guidance that allow for revenue to be recorded in the amount that the Company has a right to invoice, if that amount corresponds directly with the value to the customer of the Company’s performance to date, and that allow the Company not to disclose related unsatisfied performance obligations. The Company records any amounts that are billed to customers in excess of revenue recognized as deferred revenue and revenue recognized in excess of amounts billed to customers as unbilled receivables. Revenue streams are classified as follows: Product. Service. Generation. Advanced Technologies. See below for a discussion of revenue recognition under ASC 606 by disaggregated revenue stream. Completed project assets Contracts for the sale of completed project assets include the sale of the project asset, the assignment of the service agreement, and the assignment of the PPA. The relative stand-alone selling price is estimated and is used as the basis for allocation of the contract consideration. Revenue is recognized upon the satisfaction of the performance obligations, which includes the transfer of control of the project asset to the customer, which is when the contract is signed and the PPA is assigned to the customer. See below for further discussion regarding revenue recognition for service agreements. Contractual payments related to the sale of the project asset and assignment of the PPA are generally received up-front. Payment terms for service agreements are generally ratable over the term of the agreement. Module sales Contracts for module sales represent the sale of a completed fuel cell module at a contracted selling price. These contracts are on a per unit basis and revenue is recognized as each unit is completed and ready to ship and the performance obligation is satisfied. Payment terms for module sales are generally based on milestones achieved through the manufacturing timeline of the module. Service agreements Service agreements represent a single performance obligation whereby the Company performs all required maintenance and monitoring functions, including replacement of modules, to ensure the power platform(s) under the service agreement generate a minimum power output. To the extent the power platform(s) under service agreements do not achieve the minimum power output, certain service agreements include a performance guarantee penalty. Performance guarantee penalties represent variable consideration, which is estimated for each service agreement based on past experience, using the expected value method. The consideration for each service agreement is recognized over time using costs incurred to date relative to total estimated costs at completion to measure progress. The Company reviews its cost estimates on service agreements on an annual basis and records any changes in estimates on a cumulative catch-up basis. Loss accruals for service agreements are recognized to the extent that the estimated remaining costs to satisfy the performance obligation exceed the estimated remaining unrecognized consideration. Estimated losses are recognized in the period in which losses are identified. Payment terms for service agreements are generally ratable over the term of the agreement. Advanced Technologies contracts Advanced Technologies contracts include the promise to perform research and development services and, as such, this represents one performance obligation. Revenue from most government sponsored Advanced Technologies projects is recognized as direct costs are incurred plus allowable overhead less cost share requirements, if any. Revenue is only recognized to the extent the contracts are funded. Revenue recognition for research performed under the EMTEC Joint Development Agreement (as defined elsewhere herein) falls into the practical expedient category where revenue is recorded consistent with the amounts the Company has the right to invoice. Payments are based on costs incurred for government sponsored Advanced Technologies projects and payments under the EMTEC Joint Development Agreement are based on contractual rates for time spent and material costs incurred. Generation revenue For certain project assets where customers purchase electricity from the Company under PPAs, the Company has determined that these agreements should be accounted for as operating leases pursuant to ASC 842, Leases Variable Interest Entities and Noncontrolling Interests The Company has entered into tax equity financing transactions with certain participating companies for three partnerships (as further described in Note 3. “Tax Equity Financings and Investment Tax Credit Sale”) as of October 31, 2024. These transactions are structured as “partnership flips.” A “partnership flip” is a structure commonly used by tax equity investors in financing renewable energy projects. The Company has determined, under the power and benefits criterion of ASC 810, Consolidations ​ Sale-Leaseback Accounting The Company, through certain wholly-owned subsidiaries, has entered into sale-leaseback transactions for commissioned project assets where we have entered into a PPA with a customer who is both the site host and end user of the power. Due to the Company not meeting criteria to account for the transfer of the project assets as a sale since the leases include a repurchase right, sale accounting is precluded. Accordingly, the Company uses the financing method to account for these transactions. Under the financing method of accounting for a sale-leaseback, the Company does not derecognize the project assets and does not recognize as revenue any of the sale proceeds received from the lessor that contractually constitutes payment to acquire the assets subject to these arrangements. Instead, the sale proceeds received are accounted for as finance obligations and leaseback payments made by the Company are allocated between interest expense and a reduction to the finance obligation. Interest on the finance obligation is calculated using the Company’s incremental borrowing rate at the inception of the arrangement on the outstanding finance obligation. While we receive financing for the related project asset, we have not recognized revenue on the sale-leaseback transactions. Instead, revenue is recognized with respect to the related PPAs in accordance with the Company’s accounting policies for recognizing generation revenue. ​ Lease Accounting Right-of-use (“ROU”) assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the present value of the Company’s obligation to make lease payments arising from the lease over the lease term at the commencement date of the lease. As most of the Company’s leases do not provide an implicit rate, the Company estimated the incremental borrowing rate based on the information available at the date of adoption in determining the present value of lease payments and used the implicit rate when readily determinable. The Company determined incremental borrowing rates through market sources for secured borrowings including relevant industry rates. The Company’s operating lease ROU assets also include any lease pre-payments and exclude lease incentives. Certain of the Company’s leases include variable payments, which may vary based upon changes in facts or circumstances after the start of the lease. The Company excludes variable payments from lease ROU assets and lease liabilities to the extent not considered in-substance fixed, and instead, expenses variable payments as incurred. Variable lease expense and lease expense for short term contracts are not material components of lease expense. The Company’s leases generally have remaining lease terms of approximately 1 to 21 years, some of which include options to extend the leases. The exercise of lease renewal options is at the Company’s sole discretion and the Company’s lease ROU assets and liabilities reflect only the options the Company is reasonably certain that it will exercise. We do not have leases with residual value guarantees or similar covenants. Service Expense Recognition We warranty our products for a specific period of time against manufacturing or performance defects. Our U.S. warranty is generally limited to a term of 15 months after shipment or 12 months after acceptance of our products. We accrue for estimated future warranty costs based on historical experience. We also provide for a specific accrual if there is a known issue requiring repair during the warranty period. In addition to the standard product warranty, we have entered into service agreements with certain customers to provide monitoring, maintenance and repair services for fuel cell power platforms. Under the terms of these service agreements, the power platform must meet a minimum operating output during the term. If the minimum output falls below the contract requirement, we may be subject to performance penalties or may be required to repair and/or replace the customer’s fuel cell module(s). The Company records loss accruals for service agreements when the estimated cost of future module exchanges and maintenance and monitoring activities exceeds the remaining unrecognized contract value. Estimates for future costs on service agreements are determined by a number of factors, including the estimated remaining life of the module(s), used replacement modules available and future operating plans for the power platform. Our estimates are performed on a contract by contract basis and include cost assumptions based on what we anticipate the service requirements will be to fulfill obligations for each contract. At the end of our service agreements, customers are expected to either renew the service agreement or, based on the Company’s rights to title of the module, the module will be returned to the Company as the platform is no longer being maintained. Research and Development Costs We perform both customer-sponsored research and development projects based on contractual agreements with customers and company-sponsored research and development projects. Costs incurred for customer-sponsored projects include manufacturing and engineering labor, applicable overhead expenses, materials to build and test prototype units and other costs associated with customer-sponsored research and development contracts. Costs incurred for customer-sponsored projects are recorded as cost of Advanced Technologies contract revenues in the Consolidated Statements of Operations and Comprehensive Loss. Costs incurred for company-sponsored research and development projects consist primarily of labor, overhead, materials to build and test prototype units and consulting fees. These costs are recorded as Research and development expenses in the Consolidated Statements of Operations and Comprehensive Loss. Concentrations We contract with a concentrated number of customers for the sale of our products, for service agreements, for power purchase agreements and for Advanced Technologies contracts. For the years ended October 31, 2024, 2023 and 2022, our top customers accounted for 65%, 70% and 74%, respectively, of our total annual consolidated revenue. The percent of consolidated revenues from our top customers for the years ended October 31, 2024, 2023 and 2022, respectively, are presented below. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended October 31, ​ 2024 2023 2022 Connecticut Light and Power ​ 21 % 13 % 14 % Gyeonggi Green Energy Co., Ltd. (“GGE”) ​ 18 % — % — % Esso Nederland B.V. (“Esso”) 10 % 2 % — % ExxonMobil Technology and Engineering Company (f/k/a ExxonMobil Research and Engineering Company) (EMTEC) 8 % 8 % 8 % Ameresco/Sacramento Sewer 7 % — % — % Korea Southern Power Company (KOSPO) ​ 1 % 31 % 6 % Korea Fuel Cell Co., Ltd (KFC) ​ — % 16 % 46 % Total 65 % 70 % 74 % ​ Derivatives ​ We do not use derivatives for speculative or trading purposes. The Company has an interest rate swap that is adjusted to fair value on a quarterly basis. The estimated fair value is based on Level 2 inputs including primarily the floating Secured Overnight Financing Rate (“SOFR”) rate available to swap dealers. The valuation methodology involves comparison of (i) the sum

Revenue Recognition

Revenue Recognition	12 Months Ended
	Oct. 31, 2024
Revenue Recognition
Revenue Recognition	Note 2. Revenue Recognition Contract Balances Contract assets as of October 31, 2024 and 2023 were $65.1 million ($28.3 million long-term) and $42.1 million ($25.8 million long-term), respectively. The contract assets relate to the Company’s rights to consideration for work completed but not yet billed. These amounts are included on a separate line item as Unbilled receivables, and balances expected to be billed later than one year from the balance sheet date are included within Other assets on the accompanying Consolidated Balance Sheets. We bill customers for power platform and power platform component sales based on certain contractual milestones being reached. We bill service agreements based on the contract price and billing terms of the contracts. Generally, our Advanced Technologies contracts are billed based on actual revenues recorded, typically in the subsequent month. Some Advanced Technologies contracts are billed based on contractual milestones or costs incurred. The net change in contract assets represents amounts recognized as revenue offset by customer billings. For the years ended October 31, 2024 and 2023, a total of $16.0 million and $12.9 million, respectively, was transferred to accounts receivable from contract assets recognized at the beginning of the period. Contract liabilities as of October 31, 2024 and 2023 were $7.2 million and $3.1 million, respectively. The contract liabilities relate to the advance billings to customers for services that will be recognized over time and in some instances for deferred revenue relating to variable consideration for previously sold products. The net change in contract liabilities represents customer billings offset by revenue recognized. Consideration Payable to a Customer As of October 31, 2023, the Company had recorded $6.3 million ($6.0 million long-term) as consideration payable to Toyota Motor North America (“Toyota”), which is included within Accrued liabilities and Long-term debt and other liabilities on the accompanying Consolidated Balance Sheets. The Company received payment for the sale of an investment tax credit with respect to the Toyota project at the Port of Long Beach during the year ended October 31, 2023. The net amount of $6.3 million is being recorded as a reduction to revenue during the period of measurement, which is the 20-year Contract Modification ​ As a result of the settlement reached with POSCO Energy Co., Ltd. (“POSCO Energy”), the Company evaluated its various license agreements with POSCO Energy as well as all of the terms of the settlement agreement with POSCO Energy, which was effective December 20, 2021 (the “Settlement Agreement”). As part of this analysis, the Company considered the accounting surrounding the execution of the Settlement Agreement, reviewed all elements related to its license agreements with POSCO Energy and the Settlement Agreement and considered any potential contingencies in these license agreements and whether any proceeds were related to the litigation settlement. ​ Under the terms of the Settlement Agreement, the Company agreed that its license agreements with POSCO Energy were not terminated, but instead were deemed to be amended such that POSCO Energy and its subsidiary, Korea Fuel Cell Co., Ltd. (“KFC”, and with POSCO Energy, collectively, “PE Group”), only have the right (i) to provide maintenance and repair services to PE Group’s then existing customers on then existing molten carbonate power generation and thermal projects under long-term service agreements then in force as well as long-term service agreements that had expired and were pending renewal as of the settlement date (collectively, “Existing LTSAs”), (ii) to supply replacement modules purchased from the Company only for their existing customers for existing molten carbonate power generation and thermal projects under Existing LTSAs and (iii) to own, operate and maintain all facilities and factories solely for the purposes set forth in (i) and (ii) above (collectively, the “Right to Service License”) and further agreed to sell modules with a service warranty pursuant to a module sales agreement to be negotiated by the parties after execution of the Settlement Agreement. As such, the Company considers the execution of the Settlement Agreement to be a contract modification as it resulted in a change in both the scope and price of a contract with a customer. Therefore, the Company accounted for such modification under the contract modification guidance included within ASC 606 (Revenue from Contracts with Customers). Further, the Company noted that none of the parties to the Settlement Agreement specifically acknowledged any payment of damages or reimbursement of any costs related to the matters settled under the Settlement Agreement, which supports the conclusion that the overall settlement was a form of contract modification. Additionally, the transaction price allocated to the modified contract did not exceed the stand-alone selling prices (“SSP”) of the performance obligations under the modified contract such that there was no indication of a premium that would indicate that a portion of the transaction price related to something other than the promised goods or services. ​ The Company identified two performance obligations in the Settlement Agreement which included the sale of 20 modules and an option to purchase an additional 14 modules. The Company assessed the SSP of the modules utilizing a cost-plus margin approach to arrive at $3.0 million per module which was recognized upon transfer of control of such modules to KFC via title transfer consistent with the Company’s established revenue recognition policies. The Company is also providing a performance guarantee for up to seven years with each module to cover any annual output penalty that would need to be paid by PE Group to a customer. The Company determined that this performance guarantee represented variable consideration and estimated a value of $0.65 million per module, which resulted in accrual of $13.1 million as of October 31, 2022 upon the sale of twenty modules during the year ended October 31, 2022. A portion of this variable consideration was recognized as revenue when it was determined that there were no amounts due under the performance guarantee. In its analysis at the time of execution of the Settlement Agreement, the Company determined that it was probable that KFC would exercise its option to purchase an additional 14 modules (with a performance guarantee) beyond the firm order of 20 modules, to which it was contractually committed. KFC’s right to purchase the additional 14 modules expired without being exercised on December 31, 2022, and as a result $9.1 million was recognized as product revenue during the year ended October 31, 2023. ​ The Company signed a LTSA with Noeul Green Energy Co., Ltd. (“Noeul Green Energy”) in July 2023. Under this LTSA, once the Company, KFC/POSCO International Company, and Noeul Green Energy (the “LTSA Parties”) agreed to the technical transfer specifications under a Final Acceptance Test (the “FAT”) with respect to the transfer to Noeul Green Energy of 16 of the 20 modules previously sold by the Company to KFC pursuant to the Settlement Agreement, the LTSA Parties signed a document that released KFC/POSCO International Company from any obligations to service these modules, and concurrently transferred that obligation to the Company. The FAT is effective for 16 of the 20 modules sold to KFC pursuant to the Settlement Agreement, which are now used by Noeul Green Energy. Because the Company is no longer obligated to perform any service or other obligations under the Settlement Agreement with respect to the 16 modules now used by Noeul Green Energy, the Company recognized a ratable portion of the previously accrued variable consideration of $13.1 million which resulted in recognition of $10.5 million of product revenue during the year ended October 31, 2023. ​ EMTEC Joint Development Agreement and Rotterdam Pilot Project Purchase Order ​ Effective as of October 31, 2019, the Company entered into a Joint Development Agreement (as amended, the “EMTEC Joint Development Agreement”) with ExxonMobil Technology and Engineering Company (formerly known as ExxonMobil Research and Engineering Company) (“EMTEC”), pursuant to which the Company has engaged in exclusive research and development efforts with EMTEC to evaluate and develop new and/or improved carbonate fuel cells to reduce carbon dioxide emissions from industrial and power sources, in exchange for (i) payment by EMTEC of certain fees and costs (including research costs of up to $45.0 million) as well as certain milestone-based payments, and (ii) certain licenses . In Amendment No. 1 to the EMTEC Joint Development Agreement (“Amendment No. 1”), which was executed on October 29, 2021 and effective as of October 31, 2021, the Company and EMTEC agreed, among other things, to extend the term of the EMTEC Joint Development Agreement to April 30, 2022. Amendment No. 1 allowed for the continuation of research intended to enable incorporation of design improvements to Company fuel cell design in order to support a decision to use the improvements in a potential future demonstration of the technology for capturing carbon at an ExxonMobil refinery located in Rotterdam, Netherlands (such demonstration, the “Rotterdam Project”) and provided additional time to achieve the first milestone under the EMTEC Joint Development Agreement. In a related letter agreement between the Company and EMTEC, dated as of October 28, 2021 and executed on October 29, 2021 (the “2021 Letter Agreement”), the Company agreed to invest with EMTEC in the Rotterdam Project, should EMTEC move forward with the Rotterdam Project. In the 2021 Letter Agreement, the Company agreed that, if (i) the Company achieved the first milestone under the EMTEC Joint Development Agreement (which occurred in the first quarter of fiscal year 2022, resulting in a $5.0 million payment to the Company which the Company received in the second quarter of fiscal year 2022) and (ii) EMTEC and the Company executed a contractual agreement to proceed with the Rotterdam Project, then at EMTEC’s option, the Company would either make an investment in the amount of $5.0 million in the Rotterdam Project or discount EMTEC’s purchase of the Company’s fuel cell module and detailed engineering design, as agreed to by the parties, required for the Rotterdam Project by said amount. ​ On April 29, 2022, the Company and EMTEC entered into Amendment No. 2 (“Amendment No. 2”) to the EMTEC Joint Development Agreement, which was effective as of April 30, 2022 and which increased the maximum amount of research costs to be reimbursed by EMTEC from $45.0 million to $50.0 million and further extended the term to December 31, 2022. In Amendment No. 2, the Company and EMTEC also agreed to conduct a joint market study to (a) define application opportunities, commercialization strategies, and development requirements, (b) identify partners for potential pilot/demonstration projects and (c) assess fuel cell/stack/module manufacturing scale-up and cost reduction. ​ On December 19, 2022, the Company and EMTEC entered into Amendment No. 3 (“Amendment No. 3”) to the EMTEC Joint Development Agreement, which was effective as of December 1, 2022. In Amendment No. 3, the Company and EMTEC agreed to further extend the term of the EMTEC Joint Development Agreement such that it would end on August 31, 2023 and to further increase the maximum amount of research costs to be reimbursed by EMTEC from $50.0 million to $60.0 million. Amendment No. 3 (i) allowed for continuation of research intended to enable the parties to finalize data collection in support of the project gate decision for the Rotterdam Project, (ii) allowed for the continuation of the development, engineering and mechanical derisking of the Generation 2 Technology fuel cell module prototype, and (iii) allowed for studying the manufacturing scale-up and cost reduction of a commercial Generation 2 Technology fuel cell carbon capture facility. ​ On August 25, 2023, the Company and EMTEC entered into Amendment No. 4 to the EMTEC Joint Development Agreement (“Amendment No. 4”), effective as of August 31, 2023. In Amendment No. 4, the Company and EMTEC agreed to further extend the term of the EMTEC Joint Development Agreement such that it would end on March 31, 2024 and to further increase the maximum amount of research costs to be reimbursed by EMTEC from $60.0 million to $67.0 million. Amendment No. 4 allowed the parties the opportunity to continue (i) derisking of the Generation 2 Technology fuel cell module demonstration prototype and (ii) the joint marketing and sales efforts to inform development of a new business framework between the parties beyond the current joint development agreement structure. During the year ended October 31, 2022, the Company achieved the first technical milestone under the EMTEC Joint Development Agreement and received payment of $5.0 million. At the time, the Company did not recognize revenue in connection with this milestone achievement as a result of its agreement with EMTEC to either make a $5.0 million investment in the ​ In May 2023, the Company entered into a second letter agreement with EMTEC, pursuant to which the parties agreed that the conditions to the Company’s agreement to invest in the Rotterdam Project were met in April 2023 and, as a result, the Company would recognize $2.5 million of the $5.0 million milestone payment received in fiscal year 2022 as revenue across future deliverables to EMTEC. Of this $2.5 million, the Company recognized revenue of $1.7 million and $0.3 million during the years ended October 31, 2024 and 2023, respectively. The other $2.5 million of the $5.0 million milestone payment received under the EMTEC Joint Development Agreement in fiscal year 2022 was applied to discount EMTEC’s purchase of the Company’s fuel cell module and detailed engineering design for the Rotterdam Project. ​ On January 31, 2024, the Company received a purchase order valued at $11.6 million from Esso Nederland B.V. (“Esso”), an affiliate of Exxon Mobil Corporation and EMTEC, for fuel cell modules as well as engineering, procurement, fabrication, testing and delivery services required for the construction and implementation of the modular point source carbon capture pilot plant at the Rotterdam Project. The Company expects that this pilot plant will be completed and commissioned early in calendar year 2026. ​ On and effective as of March 31, 2024, the Company and EMTEC entered into Amendment No. 5 (“Amendment No. 5”) to the EMTEC Joint Development Agreement. In Amendment No. 5, the Company and EMTEC further extended the term of the EMTEC Joint Development Agreement such that it will end on December 31, 2026 (unless terminated earlier), so that the Company and EMTEC may pursue continued work to allow for technical readiness of the Generation 2 Technology fuel cell module as well as additional continuous technology development. In parallel with the EMTEC Joint Development Agreement, the Company and EMTEC will pursue pioneer commercial deployments of the Generation 2 Technology with third parties, with the Company as the fuel cell module manufacturer for such deployments. Amendment No. 5 also removed the cap on the maximum amount of research costs to be reimbursed by EMTEC, and instead includes an expected annual budget for the anticipated work through the remaining term of the EMTEC Joint Development Agreement of at least $10.0 million per year, subject to approval by EMTEC. ​ In addition, Amendment No. 5 provides the Company with the ability to pursue new carbon capture projects with third parties for the remaining duration of the term of the EMTEC Joint Development Agreement using Generation 1 Technology or Generation 2 Technology (provided that the use of Generation 2 Technology must be limited to the use of Generation 2 physical fuel cell properties and design elements in Generation 1 Technology modules), with any new sales of such activities, authorized work, and carbon capture projects, when summed together, having the capability of capturing no more than 250,000 tons of CO 2 ​ Long-Term Service Agreement with Gyeonggi Green Energy Co., Ltd. ​ On May 28, 2024, the Company and Gyeonggi Green Energy Co., Ltd. (“GGE”) entered into a LTSA with respect to GGE’s 58.8 MW fuel cell power platform in Hwaseong-si, Korea (the “GGE Platform”). The GGE Platform is comprised of 21 SureSource 3000 molten carbonate fuel cells (each a “Plant”). Each Plant is comprised of two 1.4-MW carbonate fuel cell modules. Pursuant to the LTSA, GGE and the Company have agreed that (i) GGE will purchase from the Company 42 1.4-MW carbonate fuel cell modules to replace existing fuel cell modules at the GGE Platform, (ii) the Company will provide certain balance of plant replacement components if and to the extent the parties reasonably determine existing components should be replaced, and (iii) the Company will provide long term operations and maintenance services for the GGE Platform. The total amount payable by GGE under the LTSA for the 42 replacement fuel cell modules, balance of plant replacement components, and service is $159.6 million USD, with payments to be made over time as such replacement fuel cell modules are commissioned and the service obligations under the LTSA for such Plants commence. Of this $159.6 million, the Company recognized revenue of $18.0 million under Product revenues, and $1.9 million under Service revenues during the year ended October 31, 2024. ​ Pursuant to the LTSA, the Company will provide various performance guarantees for each Plant related to power generation, fuel consumption, water consumption and heat production. If a Plant fails to achieve such performance requirements, the Company may be required to compensate GGE for such underperformance. ​ The Company’s service obligations under the LTSA will commence with respect to individual Plants as the Company replaces each Plant’s existing fuel cell modules and commissions the replacement fuel cell modules. The term of the LTSA with respect to each Plant will continue for seven years from the date of commissioning of the replacement fuel cell modules for such Plant. ​ Remaining Performance Obligations ​ Remaining performance obligations are the aggregate amount of total contract transaction price that is unsatisfied or partially unsatisfied. As of October 31, 2024, the Company’s total remaining performance obligations were: $172.4 million for service agreements (expected to be recognized as revenue over approximately three nineteen

Tax Equity Financings and Inves

Tax Equity Financings and Investment Tax Credit Sale	12 Months Ended
	Oct. 31, 2024
Tax Equity Financings and Investment Tax Credit Sale
Tax Equity Financings and Investment Tax Credit Sale	Note 3. Tax Equity Financings and Investment Tax Credit Sale Derby Tax Equity Financing Transaction The Company closed on a tax equity financing transaction on October 31, 2023 with Franklin Park for two fuel cell power plant installations -- the 14.0 MW Derby Fuel Cell Project and the 2.8 MW SCEF Fuel Cell Project, both located in Derby, Connecticut (collectively, the “Derby Projects”). Franklin Park’s tax equity commitment totaled $30.2 million. Of this amount, approximately $9.1 million was received on October 31, 2023 and the remaining approximately $21.1 million was received during the year ended October 31, 2024. In connection with the initial closing of this tax equity financing transaction in fiscal year 2023, the Company paid closing costs of approximately $1.8 million, which included appraisal fees, title insurance expenses and legal and consulting fees. ​ This transaction was structured as a “partnership flip”, which is a structure commonly used by tax equity investors in the financing of renewable energy projects. Under this partnership flip structure, a partnership, in this case Derby Fuel Cell Holdco, LLC (the “Derby Partnership”), was organized to acquire from FuelCell Energy Finance II, LLC, a wholly-owned subsidiary of the Company, all outstanding equity interests in the Derby Projects. FuelCell Energy Finance II owns the Derby Projects and is the party to the power purchase agreements and all project agreements. At the closing of the transaction, the Derby Projects are owned by the Derby Partnership with Franklin Park, holding the Class A Units, and Fuel Cell Energy Derby Finance Holdco, LLC holding the Class B Units. Under most partnership flip structures, tax equity investors agree to receive a minimum target rate of return, typically on an after-tax basis. Prior to receiving a contractual rate of return or a date specified in the contractual arrangements, Franklin Park will receive substantially all of the non-cash value attributable to the Derby Projects, which includes accelerated depreciation and Section 48(a) investment tax credits; however, the Company will receive a majority of the cash distributions (based on the operating income of the Derby Projects), which are to be paid quarterly. After Franklin Park receives its contractual rate of return, the Company will receive approximately 95% of the cash and tax allocations. Since the Derby Projects became operational during the first quarter of fiscal year 2024, the Company has begun to allocate profits and losses to noncontrolling interests under the HLBV method. For the year ended October 31, 2024, the net loss attributable to noncontrolling interests totaled $(28.3) million. During the year ended October 31, 2024, the Company made priority return distributions to Franklin Park of $1.0 million. There were no priority return distributions or amounts allocated to noncontrolling interest for the years ended October 31, 2023 and 2022 for the Derby Partnership because the Derby Projects were not yet operational during those years. Groton Tax Equity Financing Transaction ​ The Company closed on a tax equity financing transaction in August 2021 with East West Bancorp, Inc. (“East West Bank”) for the 7.4 MW fuel cell project located on the U.S. Navy Submarine Base in Groton, CT (the “Groton Project”). East West Bank’s tax equity commitment totals $15 million. ​ This transaction was structured as a partnership flip. Under this partnership flip structure, a partnership, in this case Groton Station Fuel Cell Holdco, LLC (the “Groton Partnership”), was organized to acquire from FuelCell Energy Finance II, LLC, a wholly-owned subsidiary of the Company, all outstanding equity interests in Groton Station Fuel Cell, LLC (the “Groton Project Company”) which in turn owns the Groton Project and is the party to the power purchase agreement and all project agreements. At the closing of the transaction, the Groton Partnership is owned by East West Bank, holding Class A Units, and Fuel Cell Energy Finance Holdco, LLC, a subsidiary of FuelCell Energy Finance, LLC, holding Class B Units. The acquisition of the Groton Project Company by the Groton Partnership was funded in part by an initial draw from East West Bank and funds contributed downstream to the Groton Partnership by the Company. The initial closing occurred on August 4, 2021, upon the satisfaction of certain conditions precedent (including the receipt of an appraisal and confirmation that the Groton Project would be eligible for the investment tax credit under Section 48 of the Internal Revenue Code of 1986, as amended). In connection with the initial closing, the Company drew down $3.0 million, of which approximately $0.8 million was used to pay closing costs including appraisal fees, title insurance expenses and legal and consulting fees. Under the original terms of the Company’s agreement with East West Bank, the Company would have been eligible to draw the remaining amount of the commitment, approximately $12 million, once the Groton Project achieved commercial operations. ​ On July 7, 2022, the Company and East West Bank amended their tax equity financing agreement and extended the commercial operations deadline to September 30, 2022. In addition, in the July 7, 2022 amendment to the tax equity financing agreement, the terms of East West Bank’s remaining investment commitment of $12.0 million were modified such that East West Bank will contribute $4.0 million on each of the first second third commercial operations. Such contributions are subject to certain customer conditions precedent, including a third-party certification by an independent engineer that the plant is operating in conformance with the amended and restated power purchase agreement. When such contributions are made by East West Bank, the funds will be distributed upstream to the Company, as a reimbursement of prior construction costs incurred by the Company. In conjunction with this amendment, the Company agreed to pay aggregate fees of $0.5 million (which are inclusive of the fees from the previous extensions of the commercial operations deadline), which were payable by the Company upon commencement of commercial operations of the plant. ​ On October 4, 2022, the Company and East West Bank further amended their tax equity financing agreement to extend the deadline by which commercial operations were to be achieved at the Groton Project from September 30, 2022 to November 30, 2022. In addition, modifications to the Groton Project documents between Connecticut Municipal Electric Energy Cooperative (“CMEEC”) and the Company as a result of the agreement between those parties to commence operations at less than 7.4 MW required the approval of East West Bank as part of East West Bank’s rights under the agreement between East West Bank and the Company. On December 16, 2022, the Company and CMEEC agreed that, for all purposes, the commercial operations date has occurred, and, accordingly, East West Bank no longer had a right to have its investment returned as a result of the Company’s failure to achieve commercial operations in a timely fashion, and this investment became a non-redeemable noncontrolling interest as of December 16, 2022. In addition, on December 16, 2022, the Company paid the aggregate fees of $0.5 million described above to East West Bank. ​ On December 16, 2022, the Company declared and, per the terms of the Amended and Restated Power Purchase Agreement between the Company and CMEEC entered into on that date (the “Amended and Restated PPA”), CMEEC agreed that the Groton Project was commercially operational at 6.0 MW. As of December 16, 2022, the Groton Project is reported as a part of the Company’s generation operating portfolio. The Amended and Restated PPA allowed the Company to operate the plants at a reduced output of approximately 6.0 MW while a Technical Improvement Plan (“TIP”) was implemented with the goal of bringing the platform to its rated capacity of 7.4 MW by December 31, 2023. In conjunction with entering into the Amended and Restated PPA, the Navy also provided its authorization to proceed with commercial operations at 6.0 MW. The Company paid CMEEC an amendment fee of $1.2 million and incurred performance guarantee fees under the Amended and Restated PPA as a result of operating at an output below 7.4 MW during implementation of the TIP. ​ During the first quarter of fiscal year 2024, the Company completed the TIP to bring the Groton Project to its rated capacity and the Groton Project reached its design rated output of 7.4 MW. The Company achieved all conditions precedent required for the first annual funding from East West Bank under the tax equity financing transaction between the Company and East West Bank and, as a result, the Company received a $4.0 million contribution during the year ended October 31, 2024 which is recorded as noncontrolling interest on the Consolidated Balance Sheets. ​ Under most partnership flip structures, tax equity investors agree to receive a minimum target rate of return, typically on an after-tax basis. Prior to receiving a contractual rate of return or a date specified in the contractual arrangements, East West Bank will receive substantially all of the non-cash value attributable to the Groton Project, which includes accelerated depreciation and Section 48(a) investment tax credits; however, the Company will receive a majority of the cash distributions (based on the operating income of the Groton Project), which are paid quarterly. After East West Bank receives its contractual rate of return, the Company will receive approximately 95% of the cash and tax allocations. The Company (through a separate wholly owned entity) entered into a back leverage debt financing transaction during fiscal year 2023 and is using the cash distributions from the Groton Partnership to service the debt (refer to Note. 12. “Debt” for additional information). During the year ended October 31, 2024, the Company made priority return distributions to East West Bank of $0.1 million. No priority return distributions were made during the years ended October 31, 2023 and 2022. For the years ended October 31, 2024 and 2023, the net loss attributable to noncontrolling interests totaled $3.5 million and $2.5 million, respectively . ​ Yaphank Tax Equity Financing Transaction ​ The Company closed on a tax equity financing transaction in November 2021 with Renewable Energy Investors, LLC (“ ​ This transaction was structured as a partnership flip. Under this partnership flip structure, a partnership, in this case YTBFC Holdco, LLC (the “Yaphank Partnership”), was organized to acquire from FuelCell Energy Finance II, LLC, a wholly-owned subsidiary of the Company, all outstanding equity interests in Yaphank Fuel Cell Park, LLC, which in turn owns the LIPA Yaphank Project and is the party to the power purchase agreement and all project agreements. . ​ The Company determined during the second quarter of fiscal year 2022 that there was an overpayment by REI of the Class A Member Capital Contribution of $0.5 million and as such the Company refunded this amount back to REI, reducing the REI tax equity commitment to $11.9 million. During the years ended October 31, 2024, 2023 and 2022, the Company made priority return distributions to REI of $0.6 million, $0 and $0.3 million, respectively, which was calculated at a 2.73% annual interest rate on invested tax equity capital. ​ Under a partnership flip structure, tax equity investors agree to receive a minimum target rate of return, typically on an after-tax basis. Prior to receiving a contractual rate of return or a date specified in the contractual arrangements, REI will receive substantially all of the non-cash value attributable to the LIPA Yaphank Project, which includes accelerated depreciation and Section 48(a) investment tax credits; however, the Company will receive a majority of the cash distributions (based on the operating income of the LIPA Yaphank Project), which are paid quarterly. After REI receives its contractual rate of return, the Company will receive approximately 95% of the cash and tax allocations. ​ Under this partnership flip structure, after the fifth anniversary following achievement of commercial operations, we have an option to acquire all of the equity interests that REI holds in the Yaphank Partnership starting after REI receives its contractual rate of return (the anticipated “flip” date) after the LIPA Yaphank Project is operational. If we exercise this option, we will be required to pay the greater of the following: (i) the fair market value of REI's equity interest at the time the option is exercised or (ii) an amount equal to 10.3% of REI’s capital contributions. This option payment is to be grossed up for federal taxes if it exceeds the tax basis of the Yaphank Partnership Class A Units. For the years ended October 31, 2024, 2023 and 2022, net income (loss) attributable to noncontrolling interest for the Yaphank Partnership totaled $0.9 million, $2.0 million and ($4.5) million, respectively . ​ Toyota Investment Tax Credit Sale On October 31, 2023, REI purchased investment tax credits (“ITCs”) from Long Beach Trigen, LLC (“LB Seller”), a subsidiary of the Company. The Toyota project qualified for $8.4 million of ITCs. The total amount of the purchase was $7.1 million or $0.85 per $1.00 of purchased ITCs. The Company incurred transaction costs of $0.4 million for legal costs and advisory fees. Toyota Motor North America (“Toyota”) has a contractual right under the Toyota HPPA to receive the benefit of the ITCs and, as a result, the Company recorded the value of the net amount due to Toyota as an accrued liability totaling $6.3 million, which will be reduced over time based on the performance under the terms of the contract with Toyota (see Note 10. “Accrued Liabilities” for further information). The balance of this accrued liability is $6.0 million as of October 31, 2024.

Restructuring

Restructuring	12 Months Ended
	Oct. 31, 2024
Restructuring
Restructuring	Note 4. Restructuring On September 5, 2024, the Company undertook a restructuring, which included a reduction in force that represented approximately 4% of the Company’s global workforce, to reduce costs and align production levels with then-current levels of demand in a manner that is consistent with the Company’s long-term strategic plan. The workforce was reduced across our global operations including Calgary, Canada and at our North American production facility in Torrington, Connecticut, at corporate offices in Danbury, Connecticut and at other remote locations. Restructuring expense relating to severance for eliminated positions of $2.6 million was recognized in the year ended October 31, 2024, which has been presented under a separate caption in the Consolidated Statements of Operations. As of October 31, 2024, $0.3 million of the restructuring expense had been paid out, and the remaining balance is included within Accrued liabilities on the accompanying Consolidated Balance Sheets. ​ Refer to Note. 22. “Subsequent Events” for additional information on the restructuring activities that were announced in November 2024. ​

Investments - Short-Term

Investments - Short-Term	12 Months Ended
	Oct. 31, 2024
Investments - Short-Term
Investments - Short-Term	Note 5. Investments – Short-Term The Company’s U.S. Treasury Securities outstanding as of October 31, 2024 had maturity dates ranging from November 5, 2024 to November 29, 2024. We have classified our investments in U.S. Treasury Securities as held-to-maturity and recorded them at amortized cost. The following table summarizes the amortized cost basis and fair value (based on quoted market prices) as of October 31, 2024 (in thousands). ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortized ​ Gross unrealized ​ Gross unrealized ​ ​ cost gains ​ losses Fair value U.S. Treasury Securities ​ ​ ​ ​ ​ ​ ​ ​ ​ As of October 31, 2024 ​ $ 109,123 $ 2 $ - $ 109,125 As of October 31, 2023 ​ $ 103,760 $ 1 $ - $ 103,761 ​ The weighted average yield to maturity as of October 31, 2024 and 2023 was 4.78% and 5.45%, respectively.

Inventories

Inventories	12 Months Ended
	Oct. 31, 2024
Inventories
Inventories	Note 6. Inventories Inventories (short and long-term) as of October 31, 2024 and 2023 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ 2024 2023 Raw materials ​ $ 35,989 ​ $ 36,200 Work-in-process (1) ​ ​ 80,457 ​ ​ 55,585 Inventories ​ ​ 116,446 ​ ​ 91,785 Inventories – current ​ ​ (113,703) ​ ​ (84,456) Inventories – long-term (2) ​ $ 2,743 ​ $ 7,329 (1) Work-in-process includes the standard components of inventory used to build the typical modules or module components that are intended to be used in future project asset construction or power platform orders or for use under the Company’s service agreements. (2) Long-term inventory includes modules that are contractually required to be segregated for use as replacement modules for a specific project asset . Raw materials consist mainly of various nickel powders and steels, various other components used in producing cell stacks and purchased components for BOP. Work-in-process inventory is comprised of material, labor, and overhead costs incurred to build fuel cell stacks and modules, which are subcomponents of a power platform.

Project Assets

Project Assets	12 Months Ended
	Oct. 31, 2024
Project Assets
Project Assets	Note 7. Project Assets Project assets as of October 31, 2024 and 2023 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ Estimated ​ 2024 2023 Useful Life Project Assets – Operating ​ $ 308,503 ​ $ 213,753 ​ 4-20 years Accumulated depreciation ​ ​ (66,542) ​ ​ (46,263) ​ ​ Project Assets – Operating, net ​ ​ 241,961 ​ ​ 167,490 ​ ​ Project Assets – Construction in progress ​ ​ 170 ​ ​ 90,576 ​ 7-20 years Project Assets, net ​ $ 242,131 ​ $ 258,066 ​ ​ ​ The estimated useful lives of these project assets are 20 years for BOP and site construction, and four installations generating power with respect to which the Company has a PPA with the end-user of power and site host with a net aggregate value of $242.0 million and $167.5 million as of October 31, 2024 and 2023, respectively. Certain of these assets are the subject of sale-leaseback arrangements with Crestmark. The increase in operating project assets as of October 31, 2024, compared to October 31, 2023, is a result of the inclusion of the Toyota project and the Derby Projects, all of which became operational during the year ended October 31, 2024. Project assets as of October 31, 2024 and 2023 also include installations with carrying values of $0.2 million and $90.6 million, respectively, which are being developed and constructed by the Company in connection with projects for which we have entered into PPAs or projects for which we expect to secure PPAs or otherwise recover the asset value and which have not yet been placed in service. Fiscal Year 2024 Charges, Including Impairment Charges The 250 kW Trinity College project and the 1.0 MW UConn project were included in “Construction in progress” as of October 31, 2024. The units to be installed at Trinity College and UConn are first article units of our solid oxide fuel cell (“SOFC”) product. In reviewing our project cost estimates for these PPAs during the third quarter of fiscal year 2024, it was determined that the expected project costs for these contracts would exceed the expected cash flows and therefore an impairment charge was required. As a result, the Company recorded an impairment charge of $1.3 million In addition, the Company incurred additional non-recoverable costs of $3.6 million associated with work at the Toyota site for the installation of ancillary equipment. This is consistent with non-recoverable costs at the Toyota project that were expensed as generation cost of revenues, as discussed in the fiscal year 2023 and fiscal year 2022 discussions below. Fiscal Year 2023 Charges, Including Impairment Charges The Toyota project was included in “Construction in progress” as of October 31, 2023. It was determined in the fourth quarter of fiscal year 2021 that a potential source of renewable natural gas (“RNG”) at favorable pricing was no longer sufficiently probable and that market pricing for RNG had significantly increased, resulting in the determination that the project was expected to generate negative cash flows and that, therefore, the carrying value of the project asset was no longer recoverable. Refer to Note 20. “Commitments and Contingencies” for more information regarding fuel risk exposure. As this project was being constructed, only inventory components that could be redeployed for alternative use were capitalized. For the year ended October 31, 2023, non-recoverable costs incurred of $22.9 million have been expensed as generation cost of revenues. During fiscal year 2023, the Company recorded an impairment charge of $2.4 million related to a project for which a PPA was ultimately not awarded. Fiscal Year 2022 Charges, Including Impairment Charges In the fourth quarter of fiscal year 2022, the Company made the decision not to proceed with development of the 7.4 MW and 1.0 MW Hartford projects given the then current economic profile of these projects. As a result, the Company recorded a $0.8 million impairment charge. Charges for the year ended October 31, 2022 relating to the Toyota project were $22.1 million, which represented the carrying value of the project asset less the carrying value of inventory components that could be redeployed for alternative use. Impairment charges are recorded as cost of generation revenues in the Consolidated Statements of Operations and Comprehensive Loss. Depreciation expense for project assets was $26.9 million, $19.0 million and $14.2 million for the years ended October 31, 2024, 2023 and 2022, respectively. Project construction costs incurred for long-term project assets are reported as investing activities in the Consolidated Statements of Cash Flows. The proceeds received from the sale and subsequent leaseback of project assets are classified as “Cash flows from financing activities” within the Consolidated Statements of Cash Flows and are classified as a finance obligation within “Current portion of long-term debt” and “Long-term debt and other liabilities” on the Consolidated Balance Sheets (refer to Note 12. “Debt” for more information).

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Oct. 31, 2024
Property, Plant and Equipment.
Property, Plant and Equipment	Note 8. Property, Plant and Equipment Property, plant and equipment as of October 31, 2024 and 2023 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ Estimated ​ ​ 2024 ​ 2023 ​ Useful Life Land ​ $ 524 ​ $ 524 ​ — Building and improvements ​ 26,581 ​ 21,430 10‑26 years Machinery, equipment and software ​ 144,242 ​ 136,554 3‑8 years Furniture and fixtures ​ 5,451 ​ 5,211 10 years Construction in progress ​ 68,588 ​ 33,950 — ​ ​ 245,386 ​ 197,669 ​ ​ Accumulated depreciation ​ (114,700) ​ (108,001) Property, plant and equipment, net ​ $ 130,686 ​ $ 89,668 ​ The Company recorded an impairment charge of approximately $1.0 million during the year ended October 31, 2022 (related to the cessation of operations at a conditioning facility in Danbury, CT, which was replaced by a new conditioning facility located at our Torrington, CT manufacturing facility). There were no impairments of property, plant and equipment for the years ended October 31, 2024 and 2023. Depreciation expense for property, plant and equipment was $8.0 million, $5.1 million and $5.8 million for the years ended October 31, 2024, 2023 and 2022, respectively.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Oct. 31, 2024
Goodwill and Intangible Assets
Goodwill and Intangible Assets	Note 9. Goodwill and Intangible Assets As of October 31, 2024 and 2023, the Company had goodwill of $4.1 million and intangible assets of $14.8 million and $16.1 million, respectively, that were recorded in connection with the Company’s 2012 acquisition of Versa Inc. and the 2019 Bridgeport Fuel Cell Project acquisition. The Versa Inc. acquisition intangible asset represents indefinite-lived IPR&D for cumulative research and development efforts associated with the development of solid oxide fuel cell stationary power generation. The Company completed its annual impairment analysis of goodwill and IPR&D assets as of July 31, 2024. The Company performed a qualitative analysis for fiscal year 2024 and determined that there was no impairment of goodwill or the indefinite-lived intangible asset. Additionally, there were no impairments of goodwill or the indefinite-lived intangible asset during fiscal years 2023 and 2022. Amortization expense for the Bridgeport Fuel Cell Project-related intangible asset was $1.3 million for each of the years ended October 31, 2024, 2023 and 2022. The following tables summarize the Company’s intangible assets as of October 31, 2024 and 2023 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of October 31, 2024 Gross Amount Accumulated Amortization Net Amount In-Process Research and Development ​ $ 9,592 ​ $ - ​ $ 9,592 Bridgeport PPA ​ ​ 12,320 ​ ​ (7,133) ​ ​ 5,187 Total ​ $ 21,912 ​ $ (7,133) ​ $ 14,779 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of October 31, 2023 Gross Amount Accumulated Amortization Net Amount In-Process Research and Development ​ $ 9,592 ​ $ - ​ $ 9,592 Bridgeport PPA ​ ​ 12,320 ​ ​ (5,836) ​ ​ 6,484 Total ​ $ 21,912 ​ $ (5,836) ​ $ 16,076 ​ Amortization expense is recorded on a straight-line basis and future amortization expense will be $1.3 million per year until the Bridgeport PPA is fully amortized.

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Oct. 31, 2024
Accrued Liabilities
Accrued Liabilities	Note 10. Accrued Liabilities Accrued liabilities as of October 31, 2024 and 2023 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ 2024 2023 Accrued payroll and employee benefits (1) ​ $ 9,808 ​ $ 7,752 Consideration payable to a customer (2) ​ ​ 2,515 ​ ​ 3,958 Accrued service agreement and PPA costs (3) ​ ​ 10,574 ​ ​ 10,742 Accrued legal, taxes, professional and other ​ ​ 5,230 ​ ​ 3,861 Accrued severance costs (4) ​ ​ 2,235 ​ ​ - Accrued liabilities ​ $ 30,362 ​ $ 26,313 (1) The balance in this account represents accrued payroll, payroll taxes and accrued bonus for both periods. The increase in the account balance relates to an increase in accrued bonus as of October 31, 2024. (2) The balance represents the net amount due to Toyota as an accrued liability which will be reduced over time based on the performance under the terms of the Toyota HPPA. (3) Accrued service agreement costs include loss accruals on service contracts of $9.0 million as of October 31, 2024, which decreased from $9.5 million as of October 31, 2023. The decrease is the result of changes in estimates regarding timing of future module exchanges and future module replacement costs. The accruals for performance guarantees on service agreements and PPAs increased from $1.2 million as of October 31, 2023 to $1.5 million as of October 31, 2024. (4) Accrued severance costs represent amounts accrued relating to restructuring activities and workforce reductions that occurred in September 2024. Refer to Note 4. “Restructuring” for more information about the restructuring.

Leases

Leases	12 Months Ended
	Oct. 31, 2024
Leases
Leases	Note 11. Leases The Company enters into operating and finance lease agreements for the use of real estate, vehicles, information technology equipment, and certain other equipment. We determine if an arrangement contains a lease at inception, which is the date on which the terms of the contract are agreed to and the agreement creates enforceable rights and obligations. The impacts of accounting for operating leases are included in Operating lease right-of-use assets, Operating lease liabilities, and Long-term operating lease liabilities in the Company’s Consolidated Balance Sheets. Finance leases are not considered significant to the Company’s Consolidated Balance Sheets or Consolidated Statements of Operations and Comprehensive Loss. Operating lease expense for the year ended October 31, 2024 was $1.4 million. Operating lease expense for each of the years ended October 31, 2023 and 2022 was $1.5 million. As of October 31, 2024, the weighted average remaining lease term (in years) was approximately 16 years and the weighted average discount rate was 6.9%. Lease payments made during the years ended October 31, 2024, 2023 and 2022 totaled $1.3 million, $1.2 million, and $1.4 million, respectively. As of October 31, 2024, undiscounted maturities of operating lease liabilities are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ Operating Leases Due Year 1 ​ $ 1,361 ​ Due Year 2 ​ ​ 1,374 ​ Due Year 3 ​ ​ 1,407 ​ Due Year 4 ​ ​ 1,375 ​ Due Year 5 ​ ​ 795 ​ Thereafter ​ ​ 11,923 ​ Total undiscounted lease payments ​ ​ 18,235 ​ Less imputed interest ​ ​ (8,534) ​ Total discounted lease payments ​ $ 9,701 ​ ​

Debt

Debt	12 Months Ended
	Oct. 31, 2024
Debt
Debt	Note 12. Debt Debt as of October 31, 2024 and 2023 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ 2024 2023 Export-Import Bank of the United States Financing Facility ​ $ 10,104 ​ $ — Liberty Bank Term Loan Agreement (Derby Senior Back Leverage Loan Facility) ​ ​ 5,825 ​ ​ — Connecticut Green Bank Term Loan Agreement (Derby Senior Back Leverage Loan Facility) ​ ​ 2,689 ​ ​ — Connecticut Green Bank Loan (Derby Subordinated Back Leverage Loan Facility) ​ ​ 3,500 ​ ​ — Connecticut Green Bank Loan (Groton Subordinated Back Leverage Loan Facility) ​ ​ 8,000 ​ ​ 8,000 Liberty Bank Term Loan Agreement (Groton Senior Back Leverage Loan Facility) ​ ​ 5,437 ​ ​ 5,876 Amalgamated Bank Loan (Groton Senior Back Leverage Loan Facility) ​ ​ 5,420 ​ ​ 5,873 Finance obligation for sale-leaseback transactions ​ ​ 18,811 ​ ​ 18,814 State of Connecticut Loan ​ ​ 6,024 ​ ​ 6,908 Finance lease obligations ​ ​ — ​ ​ 12 OpCo Financing Facility ​ ​ 70,067 ​ ​ 77,510 Deferred finance costs ​ ​ (4,215) ​ ​ (3,526) Total debt and finance obligations ​ ​ 131,662 ​ ​ 119,467 Current portion of long-term debt and finance obligations ​ ​ (15,924) ​ ​ (10,067) Long-term debt and finance obligations ​ $ 115,738 ​ $ 109,400 ​ Aggregate annual principal payments under our loan agreements, finance obligation, and finance lease obligations for the years subsequent to October 31, 2024 are as follows (in thousands): ​ ​ ​ ​ ​ Year 1 $ 14,440 Year 2 ​ 14,759 Year 3 ​ 10,930 Year 4 ​ 12,237 Year 5 ​ 11,305 Thereafter (1) ​ 61,659 ​ ​ $ 125,330 (1) The annual principal payments included above only include sale-leaseback payments whereas the difference between debt outstanding as of October 31, 2024 and the annual principal payments represent accreted interest and amounts included in the finance obligation that exceed required principal payments. ​ EXIM Financing ​ On October 31, 2024, the Company closed on a project debt financing transaction with the Export-Import Bank of the United States (“EXIM”) to support the Company’s obligations under the LTSA with GGE, pursuant to which the Company is to supply GGE with forty-two 1.4-megawatt upgraded carbonate fuel cell modules to replace existing units at GGE’s Hwaseong Baran Industrial Complex. In conjunction with this financing, the Company entered into a promissory note and related security agreements securing the loan with equipment liens, resulting in gross proceeds of approximately $10.1 million. Interest accrues at a fixed interest rate of 5.81%, and the note is repayable in monthly installments consisting of interest and principal over 7 years from the date of the first debt payment, which is due in January of 2025. After payment of customary fees and transaction costs, net proceeds were approximately $9.2 million. ​ The credit agreement between the Company and EXIM contains certain reporting requirements and other affirmative and negative covenants which are customary for transactions of this type. In addition, the Company is required to maintain, throughout the term of the credit agreement, a minimum cash balance of $100.0 million. For the purposes of this credit agreement, cash is defined as the sum of unrestricted cash plus all short-term (but no longer than three months), marketable United States Treasury instruments (as measured based on the maturity amount of each instrument). ​ Derby Back Leverage Financing ​ On April 25, 2024, FuelCell Energy Derby Finance Holdco, LLC (“Derby Holdco Borrower”), a wholly owned subsidiary of FuelCell Energy Finance, LLC (“FCEF”), which, in turn, is a wholly owned subsidiary of FuelCell Energy, Inc. (“Parent”), entered into: (i) a Credit Agreement (the “Derby Senior Back Leverage Credit Agreement”) with, by and among Liberty Bank, in its capacities as a lender (“Liberty Lender”), administrative agent (the “Senior Administrative Agent”), and lead arranger, and Connecticut Green Bank, in its capacity as a lender (“Green Bank Lender” and, collectively with Liberty Lender, the “Derby Senior Back Leverage Lenders”), for a term loan facility in an amount not to exceed an aggregate of $9.5 million to be provided 68% by Liberty Lender and 32% by Green Bank Lender (such facility, the “Derby Senior Back Leverage Loan Facility,” each such term loan, a “Derby Senior Back Leverage Loan” and such term loans together, the “Derby Senior Back Leverage Loans”); and (ii) a Credit Agreement (the “Derby Subordinated Back Leverage Credit Agreement”) with Connecticut Green Bank, as administrative agent (the “Subordinated Administrative Agent”) and lender (“Derby Subordinated Back Leverage Lender”), for a term loan facility in an amount not to exceed $3.5 million (such facility, the “Derby Subordinated Back Leverage Loan Facility” and such term loan, the “Derby Subordinated Back Leverage Loan”). The Derby Senior Back Leverage Lenders and the Derby Subordinated Back Leverage Lender are referred to collectively as the “Derby Back Leverage Lenders.” Derby Holdco Borrower’s obligations under the Derby Senior Back Leverage Credit Agreement and the Derby Subordinated Back Leverage Credit Agreement are secured by a lien on all of Derby Holdco Borrower’s assets, consisting principally of its Class B Member Interests (the “Derby Class B Interests”) in Derby Fuel Cell Holdco, LLC (the “Derby Tax Equity Holdco”). The Class A Membership Interests (the “Derby Class A Interests”) in the Derby Tax Equity Holdco are held by Franklin Park (see Note 1 for further discussion of the tax equity financing transaction structure). Derby Holdco Borrower is also the Managing Member of the Derby Tax Equity Holdco. The Derby Tax Equity Holdco’s primary asset is ownership of all of the outstanding equity interests in Derby Station Fuel Cell, LLC and SCEF1 Fuel Cell, LLC (the “Derby Project Companies”). The Derby Project Companies, in turn, are the owners of the fuel cell power plants located in Derby, Connecticut (which are referred to herein as the “Derby Projects”). As additional context concerning the relationship among the parties with respect to the Derby Senior Back Leverage Loan Facility and the Derby Subordinated Back Leverage Loan Facility more fully described below, on October 19, 2018, the Derby Project Companies and Parent entered into an Amended and Restated Power Purchase Agreement (the “Derby Amended and Restated PPA”) with The Connecticut Light and Power Company d/b/a Eversource Energy (“CLPC”), pursuant to which the Derby Project Companies agreed to sell to CLPC, and CLPC agreed to purchase from the Derby Project Companies, all of the electricity output produced by the Derby Projects pursuant to the terms and conditions of the Derby Amended and Restated PPA. At the closing (the “Derby Closing”) of each of the Derby Senior Back Leverage Loan Facility and the Derby Subordinated Back Leverage Loan Facility, which occurred simultaneously on April 25, 2024 (the “Derby Closing Date”), the entire amount of each of the Derby Senior Back Leverage Loan Facility and the Derby Subordinated Back Leverage Loan Facility was drawn down in the aggregate amount of $13.0 million. After payment of fees and transaction costs (including fees to the Derby Back Leverage Lenders and legal costs) of approximately $0.2 million in the aggregate, the remaining proceeds of approximately $12.8 million were used as follows: (i) approximately $0.9 million was used to fund debt service and module replacement reserve accounts (“DSCR Reserve Accounts”) for the Derby Senior Back Leverage Lenders in amounts of approximately $0.6 million for Liberty Lender and approximately $0.3 million for Green Bank Lender; (ii) approximately $0.4 million was used to fund a DSCR Reserve Account for the Derby Subordinated Back Leverage Lender; and (iii) the remaining amount of approximately $11.5 million was released to Parent from the Derby Back Leverage Lenders. Additionally, the Company incurred legal fees of approximately $0.2 million in relation to the financing that was not deducted from the debt proceeds. The Derby Senior Back Leverage Loan will accrue interest on the unpaid principal amount calculated from the date of such Derby Senior Back Leverage Loan until the maturity date at a rate per annum equal to 7.25%. Quarterly principal amortization and interest payments are required to be made by Derby Holdco Borrower on the Derby Senior Back Leverage Loan based on a seven-year amortization period. The Derby Senior Back Leverage Loans have a seven-year term, maturing on March 31, 2031. The Derby Subordinated Back Leverage Loan will accrue interest on the unpaid principal amount calculated from the date of such Derby Subordinated Back Leverage Loan until the maturity date at a rate per annum equal to 8%. Pursuant to the Derby Subordinated Back Leverage Loan Facility, during the “Derby Interest Only Period” (as defined below), Derby Holdco Borrower is required to make quarterly payments of interest only until June 30, 2031. Following the end of the “Derby Interest Only Period,” principal and interest payments are required to be made quarterly in quarterly level payments (“mortgage style”) of principal and interest until the maturity date on March 31, 2038. Each of the Derby Senior Back Leverage Credit Agreement and the Derby Subordinated Back Leverage Credit Agreement contains certain reporting requirements and other affirmative and negative covenants which are customary for transactions of this type. Included in the covenants are covenants that: (i) Derby Holdco Borrower maintain a “Senior” debt service coverage ratio (which is computed taking into account debt service obligations on the Derby Senior Back Leverage Loans) of not less than 1.25:1.00 (based on the trailing 12 months and tested every quarter) and a “Total” debt service coverage ratio (which is computed taking into account debt service obligations on both the Derby Senior Back Leverage Loans and the Derby Subordinated Back Leverage Loan) of not less than 1.10:1.00 (based on the trailing 12 months and tested on a quarterly basis); (ii) Derby Holdco Borrower may make distributions or dividends only if the foregoing debt to equity coverage ratios have been satisfied and Derby Holdco Borrower is not in default under any provisions of either the Derby Senior Back Leverage Credit Agreement or the Derby Subordinated Back Leverage Credit Agreement, including having made all required deposits into reserve accounts; (iii) Derby Holdco Borrower is required to exercise its right under the Derby Tax Equity Holdco limited liability company agreement to acquire the Derby Class A Interests from Franklin Park during the ninety day period beginning on the “Flip Point” (which, pursuant to the Derby Tax Equity Holdco limited liability company agreement, is the date on which the holder of Derby Class A Interests has realized a certain return on investment and, accordingly, Derby Holdco Borrower, as holder of the Derby Class B Interests, has the right to purchase the Derby Class A Interests); and (iv) the consent of the Senior Administrative Agent is required prior to Derby Holdco Borrower’s taking certain material actions under the Derby Tax Equity Holdco limited liability company agreement. Each of the Derby Senior Back Leverage Credit Agreement and the Derby Subordinated Back Leverage Credit Agreement also contains customary representations and warranties and customary events of default that cause, or entitle the Derby Back Leverage Lenders to cause, the outstanding loans to become immediately due and payable. In addition to customary events of default for transactions of this kind, the events of default include if a Change of Control occurs (meaning Parent no longer directly or indirectly owns Derby Holdco Borrower), a cross default (meaning that a default under the Derby Senior Back Leverage Loan Facility shall be deemed a default under the Derby Subordinated Back Leverage Loan Facility and vice versa) or if CLPC should become insolvent, is in bankruptcy or commits a specified number of payment defaults with regard to its payment obligations to the Derby Project Companies. The Derby Senior Back Leverage Loans may be prepaid at any time at the option of Derby Holdco Borrower provided that (i) each prepayment on or prior to the second anniversary of the Derby Closing Date shall require a prepayment fee of 3% of the principal amount being prepaid; (ii) each prepayment after the second anniversary of the Derby Closing Date but on or prior to the fourth anniversary of the Derby Closing Date shall require a prepayment fee of 2% of the principal amount being prepaid; and (iii) each prepayment after the fourth anniversary of the Derby Closing Date but on or prior to the seventh anniversary of the Derby Closing Date shall require a prepayment fee of 1% of the principal amount being prepaid. The Derby Subordinated Back Leverage Loan may be prepaid at any time without premium or penalty. ​ OpCo Financing Facility ​ On May 19, 2023, FuelCell Energy Opco Finance 1, LLC (“OpCo Borrower”), a wholly owned subsidiary of FCEF, which, in turn, is a wholly owned subsidiary of FuelCell Energy, Inc. (“Parent”), entered into a Financing Agreement (as amended, the “Financing Agreement”) with, by and among Investec Bank plc in its capacities as a lender (“Investec Lender”), administrative agent (“Administrative Agent”), and collateral agent (“Collateral Agent”); Investec, Inc. as coordinating lead arranger and sole bookrunner; Bank of Montreal (Chicago Branch) in its capacity as a lender (“BMO Lender”) and as mandated lead arranger; and each of Liberty Bank, Amalgamated Bank and Connecticut Green Bank as lenders (collectively with Investec Lender and BMO Lender, the “Lenders”) for a term loan facility in an amount not to exceed $80.5 million (the “Term Loan Facility” and such term loan, the “Term Loan”) and a letter of credit facility in an amount not to exceed $6.5 million (the “LC Facility” and together with the Term Loan Facility, the “OpCo Financing Facility”). OpCo Borrower’s obligations under the Financing Agreement are secured by Parent’s interest in six operating fuel cell generation projects: (i) the Bridgeport Fuel Cell Project, located in Bridgeport, Connecticut; (ii) the Central CT State University Project, located in New Britain, Connecticut; (iii) the Pfizer Project, located in Groton, Connecticut; (iv) the LIPA Yaphank Project, located in Long Island, New York; (v) the Riverside Regional Water Quality Control Plant Project, located in Riverside, California; and (vi) the Santa Rita Jail Project, located in Alameda County, California (each, a “Project” and collectively, the “Projects”). Immediately prior to the closing on the OpCo Financing Facility, which closing occurred on May 19, 2023, Parent caused to be transferred to OpCo Borrower all of the outstanding equity interests in: (i) Bridgeport Fuel Cell, LLC (the “Bridgeport Project Company”), the entity that owns the Bridgeport Fuel Cell Project; (ii) New Britain Renewable Energy, LLC (the “CCSU Project Company”), the entity that owns the Central CT State University Project; (iii) Groton Fuel Cell 1, LLC (the “Pfizer Project Company”), the entity that owns the Pfizer Project; (iv) Riverside Fuel Cell, LLC (the “Riverside Project Company”), the entity that owns the Riverside Regional Water Quality Control Plant Project; (v) SRJFC, LLC (the “Santa Rita Project Company”), the entity that owns the Santa Rita Jail Project; and (vi) Fuel Cell YT Holdco, LLC (the “Class B Member”), the entity that owns Parent’s Class B membership interest in YTBFC Holdco, LLC (the “Yaphank Tax Equity Partnership”), the tax equity partnership with Renewable Energy Investors, LLC (the “Class A Member”), as tax equity investor, which Yaphank Tax Equity Partnership, in turn, owns Yaphank Fuel Cell Park, LLC (the “Yaphank Project Company”), the entity that owns the LIPA Yaphank Project. ​ At the time of closing on the OpCo Financing Facility: (i) the Bridgeport Fuel Cell Project was encumbered by senior and subordinated indebtedness to Liberty Bank, Fifth Third Bank and Connecticut Green Bank in the aggregate amount of approximately $11.4 million; and (ii) the Pfizer Project, the Riverside Regional Water Quality Control Plant Project and the Santa Rita Jail Project were subject to sale and leaseback transactions and agreements with PNC Energy Capital, LLC (“PNC”) in which the lease buyout amounts, including sales taxes, were approximately $15.7 million, $3.7 million and $2.8 million, respectively. In connection with closing on the OpCo Financing Facility, all of the foregoing indebtedness and lease buyout amounts were repaid and extinguished with proceeds of the Term Loan and funds of approximately $7.3 million that were released from restricted and unrestricted reserve accounts held at PNC at the time of closing, resulting in the applicable project companies re-acquiring ownership of the three leased projects from PNC, the termination of the agreements with PNC related to the sale-leaseback transactions, and the termination of the senior and subordinated credit agreements with, the related promissory notes issued to, and the related pledge and security agreements with, Liberty Bank, Fifth Third Bank and Connecticut Green Bank related to the Bridgeport Fuel Cell Project. Further, in connection with the closing on the OpCo Financing Facility and the termination of the senior and subordinated credit agreements with Liberty Bank, Fifth Third Bank and Connecticut Green Bank related to the Bridgeport Fuel Cell Project, Fifth Third Bank and the Bridgeport Project Company agreed that the obligations arising out of the swap transactions contemplated by their related interest rate swap agreement were terminated and waived and the swap agreement was effectively terminated. In addition, in connection with closing on the OpCo Financing Facility, proceeds of the Term Loan were used to repay a portion of Parent’s long-term indebtedness to Connecticut Green Bank in the amount of approximately $1.8 million. At the closing, $80.5 million, the entire amount of the Term Loan portion of the OpCo Financing Facility, was drawn down. After payment of fees and transaction costs (including fees to the Lenders and legal costs) of approximately $2.9 million in the aggregate, the remaining proceeds of approximately $77.6 million were used as follows: (i) approximately $15.0 million was used (in addition to the approximately $7.3 million released from restricted and unrestricted reserve accounts held at PNC) to pay the lease buyout amounts and sales taxes referred to above and to re-acquire the three projects owned by PNC as referred to above; (ii) approximately $11.4 million was used to extinguish the indebtedness to Liberty Bank, Fifth Third Bank, and Connecticut Green Bank relating to the Bridgeport Fuel Cell Project; (iii) approximately $1.8 million was used to repay a portion of Parent’s long-term indebtedness to Connecticut Green Bank; (iv) $14.5 million was used to fund a capital expenditure reserve account required to be maintained pursuant to the terms and conditions of the Financing Agreement (which is classified as restricted cash on the Company’s Consolidated Balance Sheets); and (v) approximately $34.9 million was distributed to Parent for use as Parent determines in its sole discretion. In addition, in connection with the extinguishment of the Company’s indebtedness to Liberty Bank and Fifth Third Bank referred to above, approximately $11.2 million of restricted cash was released to the Company from Liberty Bank and Fifth Third Bank. Taking into consideration the release of such funds, the total net proceeds to the Company from these transactions were approximately $46.1 million. The Term Loan portion of the OpCo Financing Facility will accrue interest on the unpaid principal amount calculated from the date of such Term Loan until the maturity date thereof at a rate per annum during each Interest Period (as defined in the Financing Agreement) for such Term Loan equal to (A) with respect to SOFR Rate Loans, (i) the Adjusted Daily Compounded SOFR for such Interest Period with respect to SOFR Rate Loans plus plus Quarterly principal amortization obligations are also required to be made (based on 17-year ​ Pursuant to the terms and conditions of the Financing Agreement, OpCo Borrower is required to maintain a capital expenditures reserve to pay for expected module replacements. The total reserve balance is required to reach $29.0 million, $14.5 million of which was funded out of the closing advance of the Term Loan and the remainder of which is to be funded pursuant to an agreed upon funding schedule through cash flows generated by the Projects set forth in the Financing Agreement for the period of June 30, 2023 through December 31, 2029. Pursuant to the terms and conditions of the Financing Agreement, OpCo Borrower is required to maintain a debt service reserve of not less than six months of the scheduled principal and interest payments. The letter of credit component of the OpCo Financing Facility is for the purpose of obtaining letters of credit to satisfy such obligation; at the closing, an Irrevocable Letter of Credit was issued by Investec Bank plc as the issuing bank in favor of the Collateral Agent for the benefit of the Lenders in the amount of $6.5 million to satisfy the debt service reserve funding obligation. ​ Pursuant to the Financing Agreement, within 30 days of the financial close of the Financing Agreement, OpCo Borrower was required to enter into one or more hedge transactions, with a Lender or an affiliate thereof pursuant to one or more interest rate agreements, to hedge OpCo Borrower’s interest rate exposure relating to the Term Loan from floating to fixed. Such hedge transactions are required to be in effect at all times during the entire amortization period and have an aggregate notional amount subject to the hedge transactions at any time equal to at least 75% and no more than 105% of the aggregate principal balance of the Term Loan outstanding (taking into account scheduled amortization of the Term Loan). Upon closing, on May 19, 2023, OpCo Borrower entered into an ISDA 2002 Master Agreement and an ISDA Schedule to the 2002 Master Agreement with Investec Bank plc as a hedge provider, and an ISDA 2002 Master Agreement and an ISDA Schedule to the 2002 Master Agreement with Bank of Montreal (Chicago Branch) as a hedge provider. On May 22, 2023, OpCo Borrower executed the related trade confirmations for these interest rate swap agreements with these hedge providers to protect against adverse price movements in the floating SOFR rate associated with 100% of the aggregate principal balance of the Term Loan outstanding. Pursuant to the terms of such agreements, OpCo Borrower will pay a fixed rate of interest of 3.716%. The net interest rate across the Financing Agreement and the swap transaction is 6.366% in the first four years and 6.866% thereafter. The obligations of OpCo Borrower to the hedge providers under the interest rate swap agreements are treated as obligations under the Financing Agreement and, accordingly, are secured, on a pari passu basis, by the same collateral securing the obligations of OpCo Borrower under the Financing Agreement, which collateral is described below. The Company has not elected hedge accounting treatment and, as a result, the derivative will be remeasured to fair value quarterly, with the resulting gains/losses recorded to other income/expense. The fair value adjustments for the years ended October 31, 2024 and 2023 resulted in a loss of $3.1 million and a gain of $3.3 million, respectively. ​ The Financing Agreement contains certain reporting requirements and other affirmative and negative covenants which are customary for transactions of this type. Included in the covenants are covenants that: (i) the Yaphank Project Company obtain ongoing three year extensions of its current gas agreement; (ii) any annual operating expense budget that exceeds 115% of the Base Case Model (as defined in the Financing Agreement) for that year be approved by the Required Lenders (i.e., Lenders constituting more than 50% of the amounts loaned); (iii) OpCo Borrower maintain a debt service coverage ratio of not less than 1.20:1.00 (based on the trailing 12 months and tested every six months); and (iv) the Class B Member is required to exercise its option to purchase the Class A Member’s interest in the Yaphank Tax Equity Partnership during the six month period following the “Flip Point” as set forth in the limited liability company agreement for the Yaphank Tax Equity Partnership. The Financing Agreement also contains customary representations and warranties and customary events of default that cause, or entitle the Lenders to cause, the outstanding loans under the Financing Agreement to become immediately due and payable. The Term Loan may be prepaid at any time at the option of OpCo Borrower without premium or penalty other than any “liquidation costs” if such prepayment occurs other than at the end of an Interest Period. In addition, there are certain mandatory repayments required under the Financing Agreement, including in connection with any sale or disposition of all of the Projects or of any of the LIPA Yaphank Project, the Bridgeport Fuel Cell Project or the Pfizer Project. If the Company disposes of any of the Riverside Regional Water Quality Control Plant Project, the Santa Rita Jail Project or the Central CT State University Project, OpCo Borrower is required to prepay an amount of the Term Loan based on the then stipulated value of the disposed Project. ​ Simultaneously with OpCo Borrower entering into the Financing Agreement, FCEF (as pledgor), OpCo Borrower and each of the Bridgeport Project Company, the Pfizer Project Company, the Riverside Project Company, the Santa Rita Project Company, the CCSU Project Company and the Class B Member, each as a subsidiary grantor party and guarantor, entered into an Omnibus Guarantee, Pledge and Security Agreement (the “Security Agreement”) with Investec Bank plc as Collateral Agent, pursuant to which, as collateral for the Term Loan Facility, the LC Facility and the hedge agreements (i) FCEF granted to Collateral Agent a security interest in all of FCEF’s equity interest in OpCo Borrower; (ii) OpCo Borrower granted to Collateral Agent a security interest in all of OpCo Borrower’s assets consisting of its equity interests in the Bridgeport Project Company, the Pfizer Project Company, the Riverside Project Company, the Santa Rita Project Company, the CCSU Project Company and the Class B Member; (iii) each of the Bridgeport Project Company, the Pfizer Project Company, the Riverside Project Company, the Santa Rita Project Company and the CCSU Project Company granted to Collateral Agent a security interest in all of each such entity’s assets consisting principally of the respective generation facilities and project agreements; and (iv) the Class B Member granted to Collateral Agent a security interest in all of such Class B Member’s assets, consisting principally of its equity interest in the Yaphank Tax Equity Partnership. Pursuant to the Security Agreement, each of the subsidiary grantor parties jointly and severally guaranteed payment of all of the obligations secured by the Security Agreement. Simultaneously with the execution of the Financing Agreement, OpCo Borrower, Investec Bank plc as Collateral Agent and Administrative Agent and Liberty Bank as Depositary Agent entered into a Depositary Agreement (the “Depositary Agreement”) pursuant to which OpCo Borrower established certain accounts at Liberty Bank, all of which were pledged to Collateral Agent as security for the Term Loan Facility, the LC Facility and the hedge agreements, including a Revenue Account; a Debt Service Reserve Account; a Redemption Account (for prepayments); a Capital Expenditure Reserve Account; and a Distribution Reserve Account (in each case as defined in the Depositary Agreement). Pursuant to the terms of the Financing Agreement and the Depositary Agreement, OpCo Borrower may make quarterly distributions to FCEF and Parent provided that: (i) no Event of Default or Default (in each case as defined in the Financing Agreement) exists under the OpCo Financing Facility; (ii) all reserve accounts have been funded; (iii) no letter of credit loans or unpaid drawings are outstanding with regard to any drawn down letter of credit under the LC Facility; (iv) OpCo Borrower has maintained a greater than 1.20:1.00 debt service coverage ratio for the immediate 12 month period; and (v) no Cash Diversion Event (i.e., certain events that would adversely impact distributions to the Class B Member in connection with the LIPA Yaphank Project, as further defined in the Financing Agreement) has occurred. Beginning with the quarter ending June 2025 and continuing until the quarter ending March 2026, prior to making contributions to the Debt Service Reserve Account or the Capital Expenditure Reserve Account or having funds available for distribution, out of operating cash flow, OpCo Borrower is required to make a quarterly payment to the Administrative Agent (on behalf of the Lenders) in the amount of $675,000 per quarter to be applied to outstanding principal. ​ Groton Back Leverage Financing On August 18, 2023, FuelCell Energy Finance Holdco, LLC (“Groton Holdco Borrower”), a wholly owned subsidiary of FCEF, which, in turn, is a wholly owned subsidiary of Parent, entered into: (i) a Credit Agreement (the “Groton Senior Back Leverage Credit Agreement”) with, by and among Liberty Bank, in its capacities as a lender (“Liberty Lender”), administrative agent (the “Senior Administrative Agent”), and lead arranger, and Amalgamated Bank, in its capacity as a lender (“Amalgamated Lender” and, collectively with Liberty Lender, the “Groton Senior Back Leverage Lenders”), for a term loan facility in an amount not to exceed an aggregate of $12.0 million to be provided 50% by Liberty Lender and 50% by Amalgamated Lender (such facility, the “Groton Senior Back Leverage Loan Facility,” each such term loan, a “Groton Senior Back Leverage Loan” and such term loans together, the “Groton Senior Back Leverage Loans”); and (ii) a Credit Agreement (the “Groton Subordinated Back Leverage Credit Agreement”) with Connecticut Green Bank, as administrative agent (the “Subordinated Administrative Agent”) and lender (“Groton Subordinated Back Leverage Lender”), for a term loan facility in an amount not to exceed $8.0 million (such facility, the “Groton Subordinated Back Leverage Loan Facility” and such term loan, the “Groton Subordinated Back Leverage Loan”). The Groton Senior Back Leverage Lenders and the Groton Subordinated Back Leverage Lender are referred to collectively as the “Groton Back Leverage Lenders.” Groton Holdco Borrower’s obligations under the Groton Senior Back Leverage Credit Agreement and the Groton Subordinated Back Leverage Credit Agreement are secured by a lien on all of Groton Holdco Borrower’s assets, consisting principally of its Class B Member Interests (the “Class B Interests”) in Groton Station Fuel Cell Holdco, LLC (the “Groton Tax Equity Holdco”). Class A Membership Interests (the “Class A Interests”) in the Groton Tax Equity Holdco are held by East West Bank. Groton Holdco Borrower is also the Managing Member of the Groton Tax Equity Holdco. The Groton Tax Equity Holdco’s primary asset is ownership of all of the outstanding equity interests in Groton Station Fuel Cell, LLC (the “Groton Project Company”). The Groton Project Company, in turn, is the owner of the fuel cell power plant at the U.S. Navy Submarine Base New London located in Groton, Connecticut (the “Groton Project”). As additional context concerning the relationship among the parties with respect to the Groton Senior Back Leverage Loan Facility and the Groton Subordinated Back Leverage Loan Facility more fully described below, on December 16, 2022, the Groton Project Company and Parent entered into an Amended and Restated Power Purchase Agreement (the “Groton Amended and Restated PPA”) with Connecticut Municipal Electric Energy Cooperative (“CMEEC”), pursuant to which the Groton Project Company agreed to sell to CMEEC, and CMEEC agreed to purchase from the Groton Project Company, all of the electricity output produced by the Groton Project pursuant to the terms and conditions of the Groton Amended and Restated PPA. At the closing (the “Groton Closing”) of each of the Groton Senior Back Leverage Loan Facility and the Groton Subordinated Back Leverage Loan Facility, which occurred simulta

Stockholders' Equity and Warran

Stockholders' Equity and Warrant Liabilities	12 Months Ended
	Oct. 31, 2024
Stockholders' Equity and Warrant Liabilities
Stockholders' Equity and Warrant Liabilities	Note 13. Stockholders’ Equity and Warrant Liabilities Increase in Authorized Shares The Company obtained stockholder approval on October 10, 2023 at a Special Meeting of Stockholders to increase the number of shares of common stock the Company is authorized to issue under the Company’s Certificate of Incorporation, as amended. The Company’s stockholders approved a 500.0 million increase in the number of authorized shares of common stock. Accordingly, on October 11, 2023, the Company filed a Certificate of Amendment of the Certificate of Incorporation of the Company with the Delaware Secretary of State increasing the total number of authorized shares of common stock from 500.0 million to 1.0 billion shares. 2022 Open Market Sale Agreement and Amended Sales Agreement On July 12, 2022, the Company entered into an Open Market Sale Agreement (the “2022 Sales Agreement”) with Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canaccord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC (each, an “Agent” and together, the “Agents”) with respect to an at the market offering program under which the Company may, from time to time, offer and sell up to 3.2 million shares of the Company’s common stock. Pursuant to the 2022 Sales Agreement, the Company was required to pay and did pay each Agent a commission equal to 2.0% of the gross proceeds from each sale of shares made by such Agent under the 2022 Sales Agreement. ​ On April 10, 2024, the Company and the Agents entered into Amendment No. 1 (the “Amendment”) to the 2022 Sales Agreement (the 2022 Sales Agreement as amended by the Amendment, the “Amended Sales Agreement”), with respect to an at the market offering program under which the Company may, from time to time, offer and sell shares of the Company’s common stock having an aggregate offering price of up to $300.0 million (exclusive of any amounts previously sold under the 2022 Sales Agreement prior to its amendment). Pursuant to the Amended Sales Agreement, the Company is required to pay and has paid each Agent a commission equal to 2.0% of the gross proceeds from each sale of shares made by such Agent under the Amended Sales Agreement. ​ From the date of the Amended Sales Agreement through October 31, 2024, approximately 5.3 million shares of the Company’s common stock were sold under the Amended Sales Agreement at an average sale price of $17.93 per share, resulting in gross proceeds of approximately $95.1 million before deducting sales commissions and fees, and net proceeds to the Company of approximately $92.6 million after deducting sales commissions totaling approximately $1.9 million and fees totaling approximately $0.6 million. ​ During the year ended October 31, 2023, approximately 1.5 million shares were sold under the 2022 Sales Agreement at an average sale price of $67.49 per share, resulting in gross proceeds of approximately $99.7 million before deducting sales commissions and fees, and net proceeds to the Company of approximately $97.4 million after deducting sales commissions and fees totaling approximately $2.3 million. ​ As of October 31, 2024, approximately $ 204.9 million of shares remained available for sale under the Amended Sales Agreement. On December 27, 2024, the Company entered into Amendment No. 2 to the Amended Sales Agreement, which removes certain representations and warranties relating to the Company’s status as a well-known seasoned issuer. ​ ​

Redeemable Preferred Stock

Redeemable Preferred Stock	12 Months Ended
	Oct. 31, 2024
Redeemable Preferred Stock
Redeemable Preferred Stock	Note 14. Redeemable Preferred Stock The Company is authorized to issue up to 250,000 shares of preferred stock, par value $0.01 per share, in one or more series, of which 105,875 shares were designated as 5% Series B Cumulative Convertible Perpetual Preferred Stock (referred to herein as Series B Preferred Stock) in March 2005. Redeemable Series B Preferred Stock The Company has designated 105,875 shares of its authorized preferred stock as Series B Preferred Stock (liquidation preference $1,000.00 per share). As of October 31, 2024 and 2023, there were 64,020 shares of Series B Preferred Stock issued and outstanding, with a carrying value of $59.9 million. The following is a summary of certain terms of the Series B Preferred Stock. Ranking. ● senior to shares of the Company’s common stock; ● junior to the Company’s debt obligations; and ● effectively junior to the Company’s subsidiaries’ (i) existing and future liabilities and (ii) capital stock held by others. Dividends. The dividend rate is subject to upward adjustment as set forth in the Amended Certificate of Designation for the Series B Preferred Stock (the “Series B Certificate of Designation”) if the Company fails to pay, or to set apart funds to pay, any quarterly dividend on the Series B Preferred Stock. No dividends or other distributions may be paid or set apart for payment on the Company’s common stock (other than a dividend payable solely in shares of a like or junior ranking), nor may any stock junior to or on parity with the Series B Preferred Stock be redeemed, purchased or otherwise acquired for any consideration (or any money paid to or made available for a sinking fund for such stock) by the Company or on its behalf  (except by conversion into or exchange for shares of a like or junior ranking), unless all accumulated and unpaid dividends on the Series B Preferred Stock have been paid or funds or shares of common stock have been set aside for payment of such accumulated and unpaid dividends. The dividends on the Series B Preferred Stock will be paid in cash, unless a registered holder elects (pursuant to the procedures set forth in the Series B Certificate of Designation) to receive such dividends in shares of the Company’s common stock. Any such shares of common stock paid in lieu of cash dividends will be treated as restricted securities and will not be transferable by the recipient thereof except pursuant to an effective registration statement or pursuant to an exemption from the registration requirements of the Securities Act of 1933, as amended (the “Securities Act”). Liquidation. Conversion Rights The Company may, at its option, cause shares of Series B Preferred Stock to be automatically converted into that number of shares of its common stock that are issuable at the then-prevailing conversion rate. The Company may exercise its conversion right only if the closing price of its common stock exceeds 150% of the then-prevailing conversion price ($50,760.00 per share as of October 31, 2024) for 20 trading days during any consecutive 30 trading day period, as described in the Series B Certificate of Designation. If the holders of Series B Preferred Stock elect to convert their shares in connection with certain “fundamental changes” (as defined in the Series B Certificate of Designation and described below), the Company will in certain circumstances increase the conversion rate by a number of additional shares of common stock upon conversion or, in lieu thereof, the Company may in certain circumstances elect to adjust the conversion rate and related conversion obligation so that shares of Series B Preferred Stock are converted into shares of the acquiring or surviving company, in each case as described in the Series B Certificate of Designation. The adjustment of the conversion price is to prevent dilution of the interests of the holders of the Series B Preferred Stock from certain dilutive transactions with holders of the Company’s common stock. Redemption. (as further described in the Series B Certificate of Designation). A fundamental change will be deemed to have occurred if any of the following occurs: ● any “person” or “group” is or becomes the beneficial owner, directly or indirectly, of 50% or more of the total voting power of all classes of the Company’s capital stock then outstanding and normally entitled to vote in the election of directors; ● during any period of two consecutive years, individuals who at the beginning of such period constituted the board of directors of the Company (together with any new directors whose election to the Company’s board of directors or whose nomination for election by the stockholders was approved by a vote of 66 2/3% of the Company’s directors then still in office who were either directors at the beginning of such period or whose election or nomination for election was previously so approved) cease for any reason to constitute a majority of the directors of the Company then in office; ● the termination of trading of the Company’s common stock on The Nasdaq Stock Market and the common stock is not approved for trading or quoted on any other U.S. securities exchange or established over-the-counter trading market in the U.S.; or ● the Company (i) consolidates with or merges with or into another person or another person merges with or into the Company or (ii) sells, assigns, transfers, leases, conveys or otherwise disposes of all or substantially all of the assets of the Company and certain of its subsidiaries, taken as a whole, to another person and, in the case of any such merger or consolidation described in clause (i), the securities that are outstanding immediately prior to such transaction (and which represent 100% of the aggregate voting power of the Company’s voting stock) are changed into or exchanged for cash, securities or property, unless pursuant to the transaction such securities are changed into or exchanged for securities of the surviving person that represent, immediately after such transaction, at least a majority of the aggregate voting power of the voting stock of the surviving person. Notwithstanding the foregoing, holders of shares of the Series B Preferred Stock will not have the right to require the Company to redeem their shares if: ● the last reported sale price of shares of the Company’s common stock for any five trading days within the 10 consecutive trading days ending immediately before the later of the fundamental change or its announcement equaled or exceeded 105% of the conversion price of the Series B Preferred Stock immediately before the fundamental change or announcement; ● at least 90% of the consideration (excluding cash payments for fractional shares and in respect of dissenters’ appraisal rights) in the transaction or transactions constituting the fundamental change consists of shares of capital stock traded on a U.S. national securities exchange or quoted on The Nasdaq Stock Market, or which will be so traded or quoted when issued or exchanged in connection with a fundamental change, and as a result of the transaction or transactions, shares of Series B Preferred Stock become convertible into such publicly traded securities; or ● in the case of a merger or consolidation constituting a fundamental change (as described in the fourth bullet above), the transaction is affected solely to change the Company’s jurisdiction of incorporation. Moreover, the Company will not be required to redeem any Series B Preferred Stock upon the occurrence of a fundamental change if a third party makes an offer to purchase the Series B Preferred Stock in the manner, at the price, at the times and otherwise in compliance with the requirements set forth above and such third party purchases all shares of Series B Preferred Stock validly tendered and not withdrawn. The Company may, at its option, elect to pay the redemption price in cash, in shares of the Company’s common stock valued at a discount of 5% from the market price of shares of the Company’s common stock, or in any combination thereof. Notwithstanding the foregoing, the Company may only pay such redemption price in shares of the Company’s common stock that are registered under the Securities Act and eligible for immediate sale in the public market by non-affiliates of the Company. Voting Rights. So long as any shares of Series B Preferred Stock remain outstanding, the Company will not, without the consent of the holders of at least two-thirds of the shares of Series B Preferred Stock outstanding at the time (voting separately as a class with all other series of preferred stock, if any, on parity with the Series B Preferred Stock upon which like voting rights have been conferred and are exercisable) issue or increase the authorized amount of any class or series of shares ranking senior to the outstanding shares of the Series B Preferred Stock as to dividends or upon liquidation. In addition, the Company will not, subject to certain conditions, amend, alter or repeal provisions of the Certificate of Incorporation, as amended, including the Series B Certificate of Designation, whether by merger, consolidation or otherwise, so as to adversely amend, alter or affect any power, preference or special right of the outstanding shares of Series B Preferred Stock or the holders thereof without the affirmative vote of not less than two-thirds of the issued and outstanding shares of Series B Preferred Stock. The amendment of the Certificate of Incorporation in October 2023 did not trigger this provision.

Segment Information

Segment Information	12 Months Ended
	Oct. 31, 2024
Segment Information
Segment Information	Note 15. Segment Information We are engaged in the development, design, production, construction, and servicing of high temperature fuel cells for clean electric power generation. Critical to the success of our business is, among other things, our research and development efforts, both through customer-sponsored projects and Company-sponsored projects. The research and development activities are viewed as another product line that contributes to the development, design, production and sale of fuel cell products, however, it is not considered a separate operating segment. The chief operating decision maker does not review and assess financial information at a discrete enough level to be able to assess performance of research and development activities as if they operated as a standalone business segment, therefore, the Company has identified one business segment: fuel cell power plant production and research. Revenues, by geographic location (based on the customer’s ordering location) for the years ended October 31, 2024, 2023 and 2022 were as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 2022 United States ​ $ 86,962 ​ $ 63,289 ​ $ 60,290 South Korea ​ 22,836 ​ 58,432 ​ 68,341 Europe ​ 1,919 ​ 1,673 ​ 1,853 Canada ​ 415 ​ ​ — ​ ​ — Total ​ $ 112,132 ​ $ 123,394 ​ $ 130,484 ​ Long-lived assets located outside of the United States as of October 31, 2024 and 2023 are not significant individually or in the aggregate.

Benefit Plans

Benefit Plans	12 Months Ended
	Oct. 31, 2024
Benefit Plans
Benefit Plans	Note 16. Benefit Plans We have stockholder approved equity incentive plans, a stockholder approved Employee Stock Purchase Plan and an employee tax-deferred savings plan, which are described in more detail below. Fourth Amended and Restated 2018 Omnibus Incentive Plan At the Company’s 2024 Annual Meeting of Stockholders held on April 4, 2024 (the “2024 Annual Meeting”), the Company’s stockholders approved the amendment and restatement of the FuelCell Energy, Inc. Third Amended and Restated 2018 Omnibus Incentive Plan (as so amended and restated, the “Fourth Amended and Restated Incentive Plan”), which had previously been approved by the Company’s Board of Directors (the “Board”), subject to stockholder approval. The purpose of the amendment and restatement of the Third Amended and Restated 2018 Omnibus Incentive Plan was to authorize the Company to issue up to 833,333 additional shares of the Company’s common stock pursuant to awards under the Fourth Amended and Restated Incentive Plan. Following the approval of the amendment and restatement (and therefore the Fourth Amended and Restated Incentive Plan) by the Company’s stockholders at the 2024 Annual Meeting, the Fourth Amended and Restated Incentive Plan provides the Company with the authority to issue a total of 1,444,444 shares of the Company’s common stock. The Fourth Amended and Restated Incentive Plan authorizes grants of stock options, stock appreciation rights (“SARs”), restricted stock awards (“RSAs”), restricted stock units (“RSUs”), shares, performance shares, performance units, incentive awards and dividend equivalent units to officers, other employees, directors, consultants and advisors. Up to 61,111 shares of the Company’s common stock may be issued pursuant to the exercise of incentive stock options. Stock options, RSAs, RSUs and SARs have restrictions as to transferability. Stock option exercise prices are fixed by the Board but shall not be less than the fair market value of our common stock on the date of the grant. SARs may be granted in conjunction with stock options. The Board or the administrator of the Fourth Amended and Restated Incentive Plan may terminate the Fourth Amended and Restated Incentive Plan at any time. No award may be granted under the Fourth Amended and Restated Plan after the tenth anniversary of the approval of the Fourth Amended and Restated Plan by stockholders at the 2024 Annual Meeting Of the 1,444,444 shares of the Company’s common stock authorized to be issued under the Fourth Amended and Restated Incentive Plan as of October 31, 2024, 754,518 remained available for grant as of October 31, 2024. Of the shares remaining available for grant, the Company had reserved, for potential future grant, up to 146,397 performance stock units if maximum performance is achieved. Amended and Restated 2018 Employee Stock Purchase Plan At the 2023 Annual Meeting of Stockholders (the “2023 Annual Meeting”), the Company’s stockholders approved the amendment and restatement of the FuelCell Energy, Inc. 2018 Employee Stock Purchase Plan (as so amended and restated, the “Amended and Restated ESPP”), which had previously been approved by the Board, subject to stockholder approval. The purpose of the amendment and restatement of the 2018 Employee Stock Purchase Plan was to authorize the Company to issue up to 16,666 additional shares of the Company’s common stock under the Amended and Restated ESPP. Following the approval of the amendment and restatement (and therefore the Amended and Restated ESPP) by the Company’s stockholders at the 2023 Annual Meeting, the Amended and Restated ESPP provided the Company with the authority to issue a total of 18,055 shares of the Company’s common stock. The Amended and Restated ESPP also increased the limit on the number of shares of the Company’s common stock that any individual participant may purchase during an offering period to 33 shares. The Amended and Restated ESPP, which is intended to satisfy the requirements of Section 423 of the Internal Revenue Code of 1986, as amended, allows the Company to provide eligible employees of the Company and of certain designated subsidiaries with the opportunity to voluntarily participate in the Amended and Restated ESPP, enabling such participants to purchase shares of the Company’s common stock at a discount to market price at the time of such purchase. The Board may, in its sole discretion, terminate the Amended and Restated ESPP at any time. If the Board does not earlier terminate the Amended and Restated ESPP, the Amended and Restated ESPP will terminate on the date on which all shares of common stock available for issuance have been sold pursuant to purchase rights exercised under the Amended and Restated ESPP. Under the Amended and Restated ESPP, eligible employees have the right to purchase shares of common stock at the lesser of (i) 85% of the last reported sale price of our common stock on the first business day of the offering period, or (ii) 85% of the last reported sale price of the common stock on the last business day of the offering period, in either case rounded up to avoid impermissible trading fractions. Shares issued pursuant to the ESPP contain a legend restricting the transfer or sale of such common stock for a period of 0.5 year after the date of purchase. The ESPP activity for the years ended October 31, 2024, 2023 and 2022 was de minimis. Long-Term Incentive Plans The Company’s Board periodically approves Long Term Incentive Plans which include performance-based awards tied to the Company’s common stock price as well as time-vesting awards. None of the awards granted as part of Long-Term Incentive Plans include any dividend equivalent or other stockholder rights. To the extent the awards are earned, they may be settled in shares or cash of an equivalent value at the Company’s option. These plans are further described below. Fiscal Year 2024 Long-Term Incentive Plan Awards: On December 11, 2023, the Compensation Committee of the Board (now known as the Compensation and Leadership Development Committee) (the “Compensation Committee”) approved the specific components of, and the payout calibration for, certain awards to be made under the Company’s Long Term Incentive Plan (which is a sub-plan consisting of awards made under the Company’s 2018 Omnibus Incentive Plan, as amended and restated (the “2018 Incentive Plan”)) for fiscal year 2024. The participants in the Plan for fiscal year 2024 are members of senior management. The Plan consists of two award components for fiscal year 2024: 1) Relative Total Shareholder Return (“TSR”) Performance Share Units (“PSU”). The PSUs granted during the year ended October 31, 2024 will be earned over the performance period ending on October 31, 2026, but will remain subject to a continued service-based vesting requirement until the third anniversary of the date of grant. The performance measure for the relative TSR PSUs is the TSR of the Company relative to the TSR of the Russell 2000 from November 1, 2023 through October 31, 2026. The Compensation Committee of the Board established the performance assessment criteria for the relative TSR PSUs as the TSR of the Company relative to the TSR of the Russell 2000, with the award calibration being 100% plus or minus 0.5 x the difference between the Company’s TSR and the Russell 2000 Index composite TSR. The award is capped at 200% of the target number of PSUs, and the award is further capped at 100% of the target number of PSUs if the Company’s absolute TSR over the performance period is negative. The Company’s TSR is calculated by subtracting the Company’s beginning stock price (defined as the average closing price of the Company’s common stock over the 20 consecutive trading days ending on October 31, 2023) from the ending stock price (defined as the average closing price of the Company’s common stock over the 20 consecutive trading days ending on October 31, 2026), adding any dividends during the period, and then dividing the result by the Company’s beginning stock price. Given that the performance period is still open, the Company has reserved shares equal to 200% of the target number of PSUs, subject to performance during the remaining performance period as well as vesting based on continued service until December 11, 2026 (the third anniversary of the grant date). 2) Time-vesting RSUs. The time-vesting RSUs granted during the year ended October 31, 2024 will vest at a rate of one -third of the total number of RSUs on each of the first three anniversaries of the date of grant. Fiscal Year 2023 Long-Term Incentive Plan: On December 5, 2022, the Board approved a Long-Term Incentive Plan for fiscal year 2023 (the “FY 2023 LTI Plan”) as a sub-plan consisting of awards made under the 2018 Incentive Plan. The participants in the FY 2023 LTI Plan are members of senior management. The FY 2023 LTI Plan consists of two award components: 1) Relative Total Shareholder Return (“TSR”) Performance Share Units (“PSU”). The PSUs granted during the year ended October 31, 2023 will be earned over the performance period ending on October 31, 2025, but will remain subject to a continued service-based vesting requirement until the third anniversary of the date of grant. The performance measure for the relative TSR PSUs is the TSR of the Company relative to the TSR of the Russell 2000 from November 1, 2022 through October 31, 2025. The Compensation Committee of the Board established the performance assessment criteria for the relative TSR PSUs as the TSR of the Company relative to the TSR of the Russell 2000, with the award calibration being 100% plus or minus 0.5 x the difference between the Company’s TSR and the Russell 2000 Index composite TSR. The award is capped at 200% of the target number of PSUs, and the award is further capped at 100% of the target number of PSUs if the Company’s absolute TSR over the performance period is negative. The Company’s TSR is calculated by subtracting the Company’s beginning stock price (defined as the average closing price of the Company’s common stock over the 60 consecutive trading days ending on October 31, 2022) from the ending stock price (defined as the average closing price of the Company’s common stock over the 60 consecutive trading days ending on October 31, 2025), adding any dividends during the period, and then dividing the result by the Company’s beginning stock price. Given that the performance period is still open, the Company has reserved shares equal to 200% of the target number of PSUs, subject to performance during the remaining performance period as well as vesting based on continued service until December 5, 2025 (the third anniversary of the grant date). 2) Time-vesting RSUs. The time-vesting RSUs granted during the year ended October 31, 2023 will vest at a rate of one -third of the total number of RSUs on each of the first three anniversaries of the date of grant. Fiscal Year 2022 Long Term Incentive Plan: On December 10, 2021, the Board approved a Long-Term Incentive Plan for fiscal year 2022 (the “FY 2022 LTI Plan”) as a sub-plan consisting of awards made under the 2018 Incentive Plan. The participants in the FY 2022 LTI Plan are members of senior management. The FY 2022 LTI Plan consists of two award components: 1) Relative TSR PSU awards. The PSUs granted during the year ended October 31, 2022 were earned over the performance period ended on October 31, 2024, but remained subject to a continued service-based vesting requirement until the third anniversary of the date of grant. The performance measure for the relative TSR performance units was the TSR of the Company relative to the TSR of the Russell 2000 from November 1, 2021 through October 31, 2024. The Compensation Committee established the performance assessment criteria for the relative TSR PSUs as the TSR of the Company relative to the TSR of the Russell 2000, with the award calibration being 100% plus or minus 0.5 x the difference between the Company’s TSR and the Russell 2000 Index composite TSR. The award was capped at 200% of the target number of PSUs, and the award was further capped at 100% of the target number of PSUs if the Company’s absolute TSR over the performance period was negative. The Company’s TSR was calculated by subtracting the Company’s beginning stock price (defined as the average closing price of the Company’s common stock over the 20 consecutive trading days ending on October 31, 2021) from the ending stock price (defined as the average closing price of the Company’s common stock over the 20 consecutive trading days ending on October 31, 2024), adding any dividends during the period, and then dividing the result by the Company’s beginning stock price. On November 17, 2024, based on the calculations described above, the Compensation Committee certified awards at 52.665% of the target amount, subject to continued service until December 10, 2024 (the third anniversary of the grant date). 2) Time-vesting restricted stock units. The time-vesting RSUs granted during the year ended October 31, 2022 vest at a rate of one -third of the total number of RSUs on each of the first three anniversaries of the date of grant. Other Equity Incentive Plans The Company’s 2010 Equity Incentive Plan remains in effect only to the extent of awards outstanding under the plan as of October 31, 2024. Share-Based Compensation Share-based compensation was reflected in the Consolidated Statements of Operations and Comprehensive Loss as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended October 31, ​ ​ 2024 2023 ​ 2022 ​ Cost of revenues ​ $ 1,460 ​ $ 1,502 ​ $ 706 ​ Administrative and selling expense ​ ​ 8,583 ​ ​ 8,657 ​ ​ 5,418 ​ Research and development expense ​ ​ 1,428 ​ ​ 1,429 ​ ​ 456 ​ ​ ​ $ 11,471 ​ $ 11,588 ​ $ 6,580 ​ ​ Restricted Stock Units Including Performance Based Awards The following table summarizes our RSU and PSU activity for the year ended October 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ Restricted Stock Units ​ Shares Weighted-Average Fair Value Outstanding as of October 31, 2023 ​ ​ 217,947 ​ $ 151.89 Granted - time-vesting RSUs ​ ​ 313,883 ​ ​ 38.13 Granted - PSUs ​ ​ 109,146 ​ ​ 48.90 Vested ​ ​ (76,420) ​ ​ 210.12 Forfeited ​ ​ (47,995) ​ ​ 67.96 Outstanding as of October 31, 2024 ​ ​ 516,561 ​ $ 64.53 ​ On December 11, 2023, 218,292 RSUs were awarded to senior management under the FY 2023 LTI Plan, which included 109,146 PSUs and 109,146 time-based vesting RSUs. The 109,146 PSUs granted during the three months ended January 31, 2024 were contingent upon approval by the Company’s stockholders of additional authorized shares under the 2018 Incentive Plan, which approval was obtained at the 2024 Annual Meeting. The PSUs and time-based vesting RSUs are expensed over the three-year service period. In addition to the awards granted to senior management, during the year ended October 31, 2024, the Board also granted a total of 204,737 time-based vesting RSU awards to certain salaried employees to promote ownership of the Company’s equity and retention. The time-based vesting RSUs granted during the year ended October 31, 2024 vest at a rate of one PSUs are issued assuming participants achieve 100% target performance. The Company also reserves additional shares assuming the maximum performance targets are met. As of October 31, 2024, the Company had reserved an additional 5,849 shares for potential issuance under the FY 2022 LTI Plan, an additional 35,539 shares for potential issuance under the FY 2023 LTI Plan, and an additional 105,009 shares for potential issuance under the Long Term Incentive Plan for awards made in fiscal year 2024. RSU and PSU expense is based on the fair value of the award at the date of grant and is amortized over the vesting period, which is generally over 3 or 4 years. As of October 31, 2024, total unrecognized compensation cost related to RSUs and PSUs was $14.3 million, which is expected to be recognized over approximately the next two years on a weighted-average basis. Stock Awards During the years ended October 31, 2024, 2023 and 2022, we awarded 6,651, 3,454 and 2,562 shares, respectively, of fully vested, unrestricted common stock to the independent members of our Board as a component of Board compensation, which resulted in recognizing $0.2 million of expense for each of the years ended October 31, 2024, 2023 and 2022. Employee Tax-Deferred Savings Plans We offer a 401(k) plan (the “401(k) Plan”) to all full time employees that provides for tax-deferred salary deductions for eligible employees (beginning the first month following an employee’s hire date). Employees may choose to make voluntary contributions of their annual compensation to the 401(k) Plan, limited to an annual maximum amount as set periodically by the U.S. Internal Revenue Service (“IRS”). Employee contributions are fully vested when made. Under the 401(k) Plan, there is no option available to the employee to receive or purchase our common stock. Matching contributions of 2% under the 401(k) Plan aggregated $1.3 million, $1.1 million, and $0.5 million for the years ended October 31, 2024, 2023, and 2022, respectively.

Income Taxes

Income Taxes	12 Months Ended
	Oct. 31, 2024
Income Taxes
Income Taxes	Note 17. Income Taxes The components of loss before income taxes for the years ended October 31, 2024, 2023, and 2022 were as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 2022 U.S. ​ $ (140,713) ​ $ (95,910) ​ $ (145,439) Foreign ​ (16,040) ​ (11,565) ​ (974) Loss before income taxes ​ $ (156,753) ​ $ (107,475) ​ $ (146,413) ​ The Company recorded an income tax provision totaling $0.03 million, $0.6 million and $0.8 million for the years ended October 31, 2024, 2023 and 2022, respectively. The income tax expense primarily relates to foreign income and withholding taxes in South Korea. Franchise tax expense, which is included in administrative and selling expenses, was $0.5 million, $0.9 million and $1.0 million for the years ended October 31, 2024, 2023 and 2022, respectively. The reconciliation of the federal statutory income tax rate to our effective income tax rate for the years ended October 31, 2024, 2023 and 2022 was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 2022 Statutory federal income tax rate (21.0) % (21.0) % (21.0) % Increase (decrease) in income taxes resulting from: ​ ​ ​ ​ ​ ​ State taxes, net of Federal benefits (4.4) % (3.2) % (3.6) % Foreign withholding tax 0.1 % 0.5 % 0.6 % Net operating loss expiration, impairment and true-ups (1.1) % 6.1 % 8.7 % Nondeductible expenditures 0.2 % 2.1 % 1.4 % Change in tax rates (0.4) % 2.8 % 0.3 % Other, net 0.3 % 0.6 % 0.7 % Deferred only adjustment (0.4) % (0.1) % (0.1) % Valuation allowance 26.8 % 12.7 % 13.6 % Effective income tax rate 0.1 % 0.5 % 0.6 % ​ Our deferred tax assets and liabilities consisted of the following as of October 31, 2024 and 2023 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 Deferred tax assets: ​ ​ Compensation and benefit accruals ​ $ 7,344 ​ $ 6,026 Bad debt and other allowances ​ 2,695 ​ 1,945 Capital loss and tax credit carry-forwards ​ 16,296 ​ 14,701 Net operating losses (domestic and foreign) ​ 170,780 ​ 139,900 Deferred license revenue ​ 871 ​ 1,148 Accumulated depreciation ​ 15,969 ​ 14,051 Grant revenue ​ 210 ​ 323 Excess business interest ​ 5,860 ​ 6,406 Operating lease liabilities ​ 1,840 ​ 1,879 Capitalized research and development ​ ​ 18,305 ​ ​ 9,729 Mark-to-market ​ ​ 1,702 ​ ​ 987 Other ​ ​ 150 ​ ​ 4 Gross deferred tax assets: ​ 242,022 ​ 197,099 Valuation allowance ​ (228,139) ​ (193,477) Deferred tax assets after valuation allowance ​ 13,883 ​ 3,622 Deferred tax liability: ​ ​ ​ ​ Net loss attributable to noncontrolling interests ​ ​ (7,567) ​ ​ — In process research and development ​ (2,322) ​ (2,293) Right of use assets ​ (1,556) ​ (1,600) Other ​ ​ (2,745) ​ ​ (9) Net deferred tax liability ​ $ (307) ​ $ (280) ​ We continually evaluate our deferred tax assets as to whether it is “more likely than not” that the deferred tax assets will be realized. In assessing the realizability of our deferred tax assets, management considers the scheduled reversal of deferred tax liabilities, projected future taxable income and tax planning strategies. Based on the projections for future taxable income over the periods in which the deferred tax assets are realizable, management believes significant uncertainty exists surrounding the recoverability of the deferred tax assets. As a result, we recorded a valuation allowance against our net deferred tax assets. As of October 31, 2024, we had $1.06 billion of federal net operating loss (“NOL”) carryforwards, $549.0 million of which expire in the fiscal years 2025 through 2037, and $506.0 million of which do not expire. Due to limitations on the Company’s ability to utilize the federal NOL carryforwards, the Company has only recognized $588.0 million for financial statement purposes. As of October 31, 2024, we also had $585.1 million of state NOL carryforwards that expire in the fiscal years 2025 through 2043. Additionally, as of October 31, 2024, we had $13.7 million of state tax credits available that will expire from tax years 2025 through 2043. During the 2020 tax year, the Company experienced an “ownership change” as defined by Internal Revenue Code Section 382. As a result, the utilization of federal and state NOLs generated prior to October of 2020 is subject to limitation and a reduction was made in fiscal year 2020 to the carrying balance of the federal and state NOLs to reflect the future limitation on utilization. The Company has updated its analysis of potential ownership changes through October 31, 2024 and concluded that no additional ownership changes have occurred subsequent to October 2020. In addition, the acquisition of Versa Power Systems Ltd. in fiscal year 2013 triggered a Section 382 ownership change at the level of Versa Power Systems Ltd. which will limit the future usage of some of the federal and state NOLs that we acquired in that transaction. Accordingly, a valuation allowance has been recorded against the deferred tax asset associated with these attributes to reflect the future limitation on utilization. The Company’s financial statements reflect expected future tax consequences of uncertain tax positions that the Company has taken or expects to take on a tax return (including a decision whether to file or not file a return in a particular jurisdiction) presuming the taxing authorities’ full knowledge of the position and all relevant facts. The Company did not have any unrecognized tax benefits as of October 31, 2024 and 2023. It is our policy to record interest and penalties on unrecognized tax benefits as income taxes; however, because of our significant NOLs, no provision for interest or penalties has been recorded. We file income tax returns in the U.S. and certain states, primarily Connecticut, California and New York, as well as income tax returns required internationally for South Korea, Germany, Japan and Canada. We are open to examination by the IRS and various states in which we file for fiscal year 2004 to the present.

Loss Per Share

Loss Per Share	12 Months Ended
	Oct. 31, 2024
Loss Per Share
Loss Per Share	Note 18. Loss Per Share Basic loss per common share (“EPS”) are generally calculated as loss available to common stockholders divided by the weighted average number of common shares outstanding. Diluted EPS is generally calculated as loss available to common stockholders divided by the weighted average number of common shares outstanding plus the dilutive effect of common share equivalents. The calculation of basic and diluted EPS for the years ended October 31, 2024, 2023 and 2022 was as follows (amounts in thousands, except share and per share amounts): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended October 31, ​ ​ 2024 ​ 2023 ​ 2022 Numerator ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss attributable to FuelCell Energy, Inc. $ (126,009) ​ $ (107,568) ​ $ (142,722) ​ Series B preferred stock dividends ​ (3,200) ​ ​ (3,200) ​ ​ (3,200) ​ Net loss attributable to common stockholders $ (129,209) ​ $ (110,768) ​ $ (145,922) ​ Denominator ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding – basic ​ 16,505,257 ​ ​ 13,991,593 ​ ​ 12,771,305 ​ Effect of dilutive securities (1) ​ - ​ ​ - ​ ​ — ​ Weighted average common shares outstanding – diluted ​ 16,505,257 ​ ​ 13,991,593 ​ ​ 12,771,305 ​ Net loss to common stockholders per share – basic $ (7.83) ​ $ (7.92) ​ $ (11.43) ​ Net loss to common stockholders per share – diluted (1) $ (7.83) ​ $ (7.92) ​ $ (11.43) ​ (1) Due to the net loss to common stockholders in each of the years presented above, diluted earnings per share was computed without consideration to potentially dilutive instruments as their inclusion would have been antidilutive. As of October 31, 2024, 2023 and 2022, potentially dilutive securities excluded from the diluted loss per share calculation are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ October 31, ​ 2024 2023 ​ 2022 Outstanding options to purchase common stock ​ ​ 574 ​ ​ 610 ​ ​ 674 Unvested Restricted Stock Units ​ ​ 516,561 ​ ​ 218,105 ​ ​ 84,029 5% Series B Cumulative Convertible Perpetual Preferred Stock ​ ​ 1,261 ​ ​ 1,261 ​ ​ 1,261 Total potentially dilutive securities ​ ​ 518,396 ​ ​ 219,976 ​ ​ 85,965 ​

Restricted Cash

Restricted Cash	12 Months Ended
	Oct. 31, 2024
Restricted Cash.
Restricted Cash	Note 19. Restricted Cash As of October 31, 2024 and 2023, there was $60.8 million and $49.6 million, respectively, of restricted cash and cash equivalents pledged as performance security, reserved for future debt service requirements, and reserved for letters of credit for certain banking requirements and contracts. The allocation of restricted cash is as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ 2024 2023 Cash Restricted for Outstanding Letters of Credit (1) ​ $ 14,152 ​ $ 14,152 Cash Restricted for Crestmark Sale-Leaseback Transactions ​ ​ 2,908 ​ ​ 2,901 Debt Service and Performance Reserves related to OpCo Financing Facility ​ ​ 24,721 ​ ​ 19,698 Debt Service and Performance Reserves related to the Senior and Subordinated Back Leverage Loan Facilities ​ ​ 12,869 ​ ​ 9,294 Other ​ ​ 6,100 ​ ​ 3,579 Total Restricted Cash ​ ​ 60,750 ​ ​ 49,624 Restricted Cash and Cash Equivalents – Short-Term (2) ​ ​ (12,161) ​ ​ (5,159) Restricted Cash and Cash Equivalents – Long-Term ​ $ 48,589 ​ $ 44,465 (1) Letters of credit outstanding as of October 31, 2024 expire on various dates through October 2029. (2) Short-term restricted cash and cash equivalents are amounts expected to be released and categorized as unrestricted cash within twelve months of the balance sheet date.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Oct. 31, 2024
Commitments and Contingencies
Commitments and Contingencies	Note 20. Commitments and Contingencies Service Agreements Under the provisions of its service agreements, the Company provides services to maintain, monitor, and repair customer power plants to meet minimum operating levels. Under the terms of such service agreements, the particular power plant must meet a minimum operating output during defined periods of the term. If minimum output falls below the contract requirement, the Company may be subject to performance penalties and/or may be required to repair or replace the customer’s fuel cell module(s). Power Purchase Agreements Under the terms of the Company’s PPAs, customers agree to purchase power from the Company’s fuel cell power plants at negotiated rates. Electricity rates are generally a function of the customers’ current and estimated future electricity pricing available from the grid. As owner or lessee of the power plants, the Company is responsible for all operating costs necessary to maintain, monitor and repair the power plants. Under certain agreements, the Company is also responsible for procuring fuel, generally natural gas or biogas, to run the power plants. In addition, under the terms of some of the PPAs, the Company may be subject to a performance penalty if the Company does not meet certain performance requirements. Project Fuel Exposure ​ Certain of our PPAs for project assets in our generation operating portfolio expose us to fluctuating fuel price risks as well as the risk of being unable to procure the required amounts of fuel and the lack of alternative available fuel sources. We seek to mitigate our fuel risk using strategies including: (i) fuel cost reimbursement mechanisms in our PPAs to allow for pass through of fuel costs (full or partial) where possible, which we have done with our 14.9 MW operating project in Bridgeport, CT; (ii) procuring fuel under fixed price physical supply contracts with investment grade counterparties, which we have done for twenty years for our Tulare BioMAT project, the initial seven years of the twenty year PPA for our LIPA Yaphank Project (through September 2028), six years of the twenty year PPA for our 14.0 MW and 2.8 MW Derby Projects (through October 2029), and the initial two years of the twenty year hydrogen power purchase agreement for our Toyota project (through May of 2025); and (iii) potentially entering into future financial hedges with investment grade counterparties to offset potential negative market fluctuations. If the Company is unable to secure fuel on favorable economic terms, it may result in impairment charges to the Derby and Yaphank project assets and further charges for the Toyota project asset. ​ The Company net settled certain natural gas purchases under previous normal purchase normal sale contract designations during the fourth quarter of fiscal year 2023 for one contract and the second quarter of fiscal year 2024 for other contracts, which resulted in a change to mark-to-market accounting. The Company recorded a mark-to-market net loss of $6.9 million and a mark-to-market net gain of $4.1 million associated with the natural gas contract derivatives for the years ended October 31, 2024 and 2023, respectively. The Company has recorded derivative assets within other assets on the Consolidated Balance Sheets, which had an estimated fair value of $1.2 million and $4.1 million as of October 31, 2024 and October 31, 2023, respectively. The Company has recorded derivative liabilities within long-term debt and other liabilities on the Consolidated Balance Sheets, which had an estimated fair value of $4.0 million and $0 as of October 31, 2024 and October 31, 2023, respectively. The natural gas contract derivatives are classified as Level 2 financial assets/liabilities since the values can be determined based on readily observable inputs for underlying natural gas forward prices. ​ Other As of October 31, 2024, the Company had unconditional purchase commitments aggregating $90.8 million, for materials, supplies and services in the normal course of business. Legal Proceedings From time to time, the Company is involved in legal proceedings, including, but not limited to, regulatory proceedings, claims, mediations, arbitrations and litigation, arising out of the ordinary course of its business (“Legal Proceedings”). Although the Company cannot assure the outcome of such Legal Proceedings, management presently believes that the result of such Legal Proceedings, either individually, or in the aggregate, will not have a material adverse effect on the Company’s consolidated financial statements, and no material amounts have been accrued in the Company’s consolidated financial statements with respect to these matters.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	12 Months Ended
	Oct. 31, 2024
Supplemental Cash Flow Information
Supplemental Cash Flow Information	Note 21. Supplemental Cash Flow Information The following represents supplemental cash flow information (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended October 31, ​ 2024 2023 2022 Cash interest paid ​ $ 6,796 ​ $ 3,088 ​ $ 1,556 Income taxes paid ​ 16 ​ 6 ​ 2 Noncash financing and investing activity: ​ ​ ​ ​ ​ Noncash reclassifications between inventory and project assets ​ 4,586 ​ 1,987 ​ 1,260 Noncash reclassifications from inventory to fixed assets ​ ​ — ​ ​ — ​ ​ 1,552 Noncash reclassifications from other assets to project assets ​ ​ — ​ ​ — ​ ​ 2,375 Director stock compensation ​ 159 ​ 225 ​ 305 Accrued noncontrolling interest distribution ​ ​ — ​ ​ 148 ​ ​ — Addition of operating lease liabilities ​ 395 ​ 1,952 ​ — Addition of operating lease right-of-use assets ​ 395 ​ 1,952 ​ — Noncash reduction in basis of project assets ​ — ​ 6,330 ​ — Accrued purchase of fixed assets, cash paid to be paid in subsequent period ​ 2,958 ​ 1,646 ​ 4,396 Accrued purchase of project assets, cash to be paid in subsequent period ​ 269 ​ 4,515 ​ 6,444 ​

Subsequent Events

Subsequent Events	12 Months Ended
	Oct. 31, 2024
Subsequent Events
Subsequent Events	Note 22. Subsequent Events Global Restructuring ​ On November 15, 2024, the Company announced a global restructuring of its operations in the U.S., Canada and Germany that aims to reduce operating costs, realign resources toward advancing the Company’s core technologies, and protect the Company’s competitive position amid slower-than-expected investments in clean energy. In connection with the restructuring plan, the Company reduced its workforce by approximately 13% or 75 employees in November 2024. ​ The actions under the restructuring plan are expected to be substantially completed by the end of the first quarter of fiscal year 2025. In connection with the restructuring plan and workforce reduction, the Company estimates it will incur aggregate restructuring-related costs and charges of approximately $1.7 million to $2.0 million in cash costs related to severance payments and other employee termination benefits. These charges are expected to be recorded in the first quarter of fiscal year 2025. ​ Groton Tax Equity Financing Transaction During the first quarter of fiscal year 2025, on December 12, 2024 the Company closed on the second annual funding related to the tax equity financing for the Groton Project. The Company achieved all conditions precedent required for the second annual funding from East West Bank under the tax equity financing transaction between the Company and East West Bank and, as a result, the Company received a $4.0 million contribution which will be recorded as noncontrolling interest on the Consolidated Balance Sheets. ​ ​ ​

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (126,009)	$ (107,568)	$ (142,722)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Oct. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Insider Trading Policies and Pr

Insider Trading Policies and Procedures	12 Months Ended
	Oct. 31, 2024
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Nature of Business, Basis of _2

Nature of Business, Basis of Presentation and Significant Accounting Policies (Policies)	12 Months Ended
	Oct. 31, 2024
Nature of Business, Basis of Presentation and Significant Accounting Policies
Nature of Business and Basis of Presentation	Nature of Business and Basis of Presentation Headquartered in Danbury, Connecticut, FuelCell Energy, Inc. (together with its subsidiaries, the “Company” “FuelCell Energy,” “we,” “us,” or “our”) is a global leader in delivering environmentally responsible distributed baseload energy platform solutions through our proprietary fuel cell technology. Today, we offer commercial technology that produces clean electricity, heat, clean hydrogen, and water and is also capable of recovering and capturing carbon for utilization and/or sequestration, depending on product configuration and application. We also continue to invest in product development and commercializing technologies that are expected to add new capabilities to our platforms’ abilities to deliver hydrogen and long duration hydrogen-based energy storage through our solid oxide technologies, as well as further enhance our existing platforms’ carbon capture solutions. ​ FuelCell Energy is focused on advancing sustainable clean energy technologies that address some of the world’s most critical challenges around energy access, security, resilience, reliability, affordability, safety and environmental stewardship. As a leading global manufacturer of proprietary fuel cell technology platforms, FuelCell Energy is uniquely positioned to serve customers worldwide with sustainable products and solutions for industrial and commercial businesses, utilities, governments, municipalities, and communities. ​ The consolidated financial statements include our accounts, those of our wholly-owned subsidiaries, and those of our consolidated variable interest entities. All intercompany accounts and transactions have been eliminated. At 5:00 p.m. Eastern Time on November 8, 2024, we effected a 1
Liquidity	Liquidity Our principal sources of cash have been proceeds from the sale of our products and projects, electricity generation revenues, research and development and service agreements with third parties, sales of our common stock through public equity offerings, and proceeds from debt, project financing and tax monetization transactions. We have utilized this cash to accelerate the commercialization of our solid oxide platforms, develop new capabilities to separate and capture carbon, develop and construct project assets, invest in capital improvements and expansion of our operations, perform research and development, pay down existing outstanding indebtedness, and meet our other cash and liquidity needs. As of October 31, 2024, unrestricted cash and cash equivalents totaled $148.1 million compared to $250.0 million as of October 31, 2023. During the years ended October 31, 2024 and 2023, the Company invested in United States (U.S.) Treasury Securities. The amortized cost of the U.S. Treasury Securities outstanding totaled $109.1 million as of October 31, 2024 compared to $103.8 million as of October 31, 2023 and is classified as Investments - short-term on the Consolidated Balance Sheets. The outstanding U.S. Treasury Securities as of October 31, 2024 matured between November 5, 2024 and November 29, 2024. On October 31, 2024, the Company closed on a project debt financing transaction with the Export-Import Bank of the United States (“EXIM”) to support the Company’s obligations under its long-term service agreement with Gyeonggi Green Energy Co., Ltd. (“GGE”), pursuant to which the Company is to supply forty-two 1.4-megawatt upgraded carbonate fuel cell modules to replace existing units at GGE’s Hwaseong Baran Industrial Complex. In conjunction with this financing, the Company entered into a promissory note and related security agreements securing the loan with equipment liens, resulting in net proceeds of approximately $9.2 million. See Note 12. “Debt” for additional information regarding the transaction with EXIM. ​ On April 25, 2024, the Company (through one of its indirect subsidiaries) entered into three related term loan facilities (which are referred to herein as the “Derby Senior Back Leverage Loan Facility” and the “Derby Subordinated Back Leverage Loan Facility”), resulting in net proceeds of $12.8 million. See Note 12. “Debt” for additional information regarding the Derby Senior Back Leverage Loan Facility and the Derby Subordinated Back Leverage Loan Facility. ​ On April 10, 2024, the Company entered into Amendment No. 1 (the “Amendment”) to the Open Market Sale Agreement, dated July 12, 2022 (the “2022 Sales Agreement”), with Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canaccord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC (each, an “Agent” and together, the “Agents”) (the 2022 Sales Agreement as amended by the Amendment, the “Amended Sales Agreement”), with respect to an at the market offering program under which the Company may, from time to time, offer and sell shares of its common stock having an aggregate offering price of up to $300.0 million (exclusive of any amounts previously sold under the 2022 Sales Agreement prior to its amendment). Between April 10, 2024 (the date of the Amended Sales Agreement) and October 31, 2024, approximately 5.3 million shares of the Company’s common stock were sold under the Amended Sales Agreement resulting in gross proceeds of approximately $95.1 million. On December 27, 2024, the Company entered into Amendment No. 2 to the Amended Sales Agreement, which removes certain representations and warranties relating to the Company’s status as a well-known seasoned issuer. See Note 13. “Stockholders’ Equity and Warrant Liabilities” for additional information regarding the 2022 Sales Agreement and the Amended Sales Agreement. ​ During the first quarter of fiscal year 2024, the Company completed its technical improvement plan to bring the Groton Project (defined elsewhere herein) to its rated capacity and the Groton Project reached its design rated output of 7.4 MW. The Company achieved all conditions precedent required for the first annual funding from East West Bancorp, Inc. (“East West Bank”) under the tax equity financing transaction between the Company and East West Bank and, as a result, the Company received a $4.0 million contribution during the year ended October 31, 2024 which is recorded as noncontrolling interest on the Consolidated Balance Sheets. ​ During the fourth quarter of fiscal year 2023, the Company closed on a tax equity financing transaction with Franklin Park 2023 FCE Tax Equity Fund, LLC (“Franklin Park”), a subsidiary of Franklin Park Infrastructure, LLC, for two fuel cell power plant installations -- the 14.0 megawatt (“MW”) Derby Fuel Cell Project and the 2.8 MW SCEF Fuel Cell Project, both located in Derby, Connecticut (collectively, the “Derby Projects”). Franklin Park’s tax equity commitment with respect to the Derby Projects totaled $30.2 million. Of this amount, approximately $9.1 million was received on October 31, 2023 and the remaining approximately $21.1 million was received during the year ended October 31, 2024. In connection with the initial closing of this tax equity financing transaction in fiscal year 2023, the Company paid closing costs of approximately $1.8 million, which included appraisal fees, title insurance expenses and legal and consulting fees. ​ We believe that our unrestricted cash and cash equivalents, expected receipts from our contracted backlog, funds received upon the maturity of U.S. Treasury Securities, and release of short-term restricted cash less expected disbursements over the next twelve months will be sufficient to allow the Company to meet its obligations for at least one year from the date of issuance of these financial statements. ​ To date, we have not achieved profitable operations or sustained positive cash flow from operations. The Company’s future liquidity, for fiscal year 2025 and in the long-term, will depend on its ability to (i) timely complete current projects in process within budget, (ii) increase cash flows from its generation operating portfolio, including by meeting conditions required to timely commence operation of new projects, operating its generation operating portfolio in compliance with minimum performance guarantees and operating its generation operating portfolio in accordance with revenue expectations, (iii) obtain financing for project construction and manufacturing expansion, (iv) obtain permanent financing for its projects once constructed, (v) increase order and contract volumes, which would lead to additional product sales, service agreements and generation revenues, (vi) obtain funding for and receive payment for research and development under current and future Advanced Technologies contracts, (vii) successfully commercialize its solid oxide, hydrogen and carbon capture platforms, (viii) implement capacity expansion for solid oxide product manufacturing, (ix) implement the product cost reductions necessary to achieve profitable operations, (x) manage working capital and the Company’s unrestricted cash balance and (xi) access the capital markets to raise funds through the sale of debt and equity securities, convertible notes, and other equity-linked instruments. We are continually assessing different means by which to accelerate the Company’s growth, enter new markets, commercialize new products, and enable capacity expansion. Therefore, from time to time, the Company may consider and enter into agreements for one or more of the following: negotiated financial transactions, minority investments, collaborative ventures, technology sharing, transfer or other technology license arrangements, joint ventures, partnerships, acquisitions or other business transactions for the purpose(s) of geographic or manufacturing expansion and/or new product or technology development and commercialization, including hydrogen production through our carbonate and solid oxide platforms and storage and carbon capture, sequestration and utilization technologies. Our business model requires substantial outside financing arrangements and satisfaction of the conditions of such arrangements to construct and deploy our projects to facilitate the growth of our business. The Company has invested capital raised from sales of its common stock to build out its project portfolio. The Company has also utilized and expects to continue to utilize a combination of long-term debt and tax equity financing (e.g., sale-leaseback transactions, partnership flip transactions and the monetization and/or transfer of eligible investment and production tax credits) to finance its project asset portfolio as these projects commence commercial operations, particularly in light of the passage of the Inflation Reduction Act in August 2022. The Company may also seek to undertake private placements of debt securities to finance its project asset portfolio. The proceeds of any such financing, if obtained, may allow the Company to reinvest capital back into the business and to fund other projects. We also expect to seek additional financing in both the debt and equity markets in the future. If financing is not available to us on acceptable terms if and when needed, or on terms acceptable to us or our lenders, if we do not satisfy the conditions of our financing arrangements, if we spend more than the financing approved for projects, if project costs exceed an amount that the Company can finance, or if we do not generate sufficient revenues or obtain capital sufficient for our corporate needs, we may be required to further reduce or slow planned spending, further reduce staffing, sell assets, seek alternative financing and take other measures, any of which could have a material adverse effect on our financial condition and operations.
Cash and Cash Equivalents	Cash and Cash Equivalents All cash equivalents consist of investments in money market funds with original maturities of three months or less at the date of acquisition. We place our temporary cash equivalent investments with high credit quality financial institutions.
Inventories and Advance Payments to Vendors	Inventories and Advance Payments to Vendors Inventories consist principally of raw materials and work-in-process. Cost is determined using the first-in, first-out cost method. Included in our inventory balance are used modules that are brought back into inventory upon installation of new modules. When a new module is installed, a determination is made as to whether the used module has remaining useful life or should be scrapped and materials recycled. Modules that are deemed to have remaining useful life are put into inventory at an estimated value based on the expected remaining life of the module and its projected output. In certain circumstances, we will make advance payments to vendors for future inventory deliveries. These advance payments are recorded as Other current assets on the Consolidated Balance Sheets. Inventories are reviewed to determine net realizable value. This review includes analyzing inventory levels of individual parts considering the current design of our products and production requirements as well as the expected inventory requirements for maintenance on installed power platforms.
Investments - Short-Term	Investments – Short-Term The Company invests in U.S. Treasury Securities which are held-to-maturity and are recorded at amortized cost.
Allowance for Doubtful Accounts and Credit Losses	Allowance for Doubtful Accounts and Credit Losses The Company had no allowance for doubtful accounts or credit losses as of October 31, 2024 and 2023. Uncollectible accounts receivable are charged against the allowance for doubtful accounts when all collection efforts have failed and it is deemed unlikely that the amount will be recovered. The Company would record a specific reserve for individual accounts when the Company becomes aware of specific customer circumstances such as in the case of a bankruptcy filing or the deterioration in the customer’s operating results or financial position.
Project Assets	Project Assets Project assets consist of capitalized costs for fuel cell projects in various stages of development, including those projects with respect to which we have entered into power purchase agreements (“PPAs”) and those projects with respect to which we expect to secure long-term contracts. Such development costs are generally incurred prior to entering into a definitive sales or long-term financing agreement for the project. Project assets also include capitalized costs for fuel cell projects which are the subject of sale-leaseback transactions with Crestmark Equipment Finance, a division of MetaBank (“Crestmark”). Project asset costs include costs for developing and constructing a complete turn-key fuel cell project. Development costs can include legal, consulting, permitting, interconnect, and other similar costs. To the extent we enter into a definitive sales agreement, we expense project assets to cost of sales after the respective project asset is sold to a customer and all revenue recognition criteria have been met.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are stated at cost, less accumulated depreciation which is recorded based on the straight-line method over the estimated useful lives of the respective assets. Leasehold improvements are amortized on the straight-line method over the shorter of the estimated useful lives of the assets or the term of the lease. When property, plant or equipment is sold or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and any resulting gain or loss is reflected in operations for the period.
Goodwill and Indefinite-Lived Intangibles	Goodwill and Indefinite-Lived Intangibles Goodwill represents the excess of the aggregate purchase price over the fair value of the net assets acquired in a business combination and is reviewed for impairment at least annually. The intangible asset represents indefinite-lived in-process research and development (“IPR&D”) for cumulative research and development efforts associated with the development of solid oxide fuel cell stationary power generation and is also reviewed at least annually for impairment. Accounting Standards Codification (“ASC”) Topic 350: Intangibles - Goodwill and Other The Company completed its annual impairment analysis of goodwill and IPR&D as of July 31, 2024. The goodwill and IPR&D asset are both held by the Company’s Versa Power Systems, Inc. (“Versa Inc.”) reporting unit. Goodwill and the IPR&D asset are also reviewed for possible impairment whenever changes in conditions indicate that the fair value of a reporting unit or IPR&D asset is more likely than not below its respective carrying value. No impairment charges were recorded with respect to goodwill or the IPR&D asset during the fiscal years ended October 31, 2024, 2023 and 2022.
Impairment of Long-Lived Assets (including Project Assets)	Impairment of Long-Lived Assets (including Project Assets) Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset group may not be recoverable. If events or changes in circumstances indicate that the carrying amount of the asset group may not be recoverable, we compare the carrying amount of the asset group to the future undiscounted net cash flows, excluding debt service costs, expected to be generated by the asset group and its ultimate disposition. If the sum of the undiscounted cash flows is less than the carrying value, the impairment to be recognized is measured by the amount by which the carrying amount of the asset group exceeds its fair value.
Revenue Recognition	Revenue Recognition The Company recognizes revenue in accordance with ASC Topic 606: Revenue from Contracts with Customers A contract is accounted for when there has been approval and commitment from both parties, the rights of the parties are identified, payment terms are identified, the contract has commercial substance and collectability of consideration is probable. Performance obligations under a contract are identified based on the goods or services that will be transferred to the customer that are both capable of being distinct and are distinct in the context of the contract. In certain instances, the Company has concluded distinct goods or services should be accounted for as a single performance obligation that is a series of distinct goods or services that have the same pattern of transfer to the customer. To the extent a contract includes multiple promised goods or services, the Company must apply judgment to determine whether the customer can benefit from the goods or services either on their own or together with other resources that are readily available to the customer (the goods or services are capable of being distinct) and if the promise to transfer the goods or services to the customer is separately identifiable from other promises in the contract (the goods or services are distinct in the context of the contract). If these criteria are not met, the promised goods or services are accounted for as a single performance obligation. The transaction price is determined based on the consideration that the Company will be entitled to in exchange for transferring goods or services to the customer. To the extent the transaction price includes variable consideration, the Company estimates the amount of variable consideration that should be included in the transaction price, generally utilizing the expected value method. Determining the transaction price requires judgment. If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price to each performance obligation based on a relative standalone selling price basis. Standalone selling price is determined by the price at which the performance obligation is sold separately. If the standalone selling price is not observable through past transactions, the Company estimates the standalone selling price by taking into account available information such as market conditions and internally approved pricing guidelines related to the performance obligations. Performance obligations are satisfied either over time or at a point in time as discussed in further detail below. In addition, the Company’s contracts with customers generally do not include significant financing components or non-cash consideration. The Company has elected practical expedients in the accounting guidance that allow for revenue to be recorded in the amount that the Company has a right to invoice, if that amount corresponds directly with the value to the customer of the Company’s performance to date, and that allow the Company not to disclose related unsatisfied performance obligations. The Company records any amounts that are billed to customers in excess of revenue recognized as deferred revenue and revenue recognized in excess of amounts billed to customers as unbilled receivables. Revenue streams are classified as follows: Product. Service. Generation. Advanced Technologies. See below for a discussion of revenue recognition under ASC 606 by disaggregated revenue stream. Completed project assets Contracts for the sale of completed project assets include the sale of the project asset, the assignment of the service agreement, and the assignment of the PPA. The relative stand-alone selling price is estimated and is used as the basis for allocation of the contract consideration. Revenue is recognized upon the satisfaction of the performance obligations, which includes the transfer of control of the project asset to the customer, which is when the contract is signed and the PPA is assigned to the customer. See below for further discussion regarding revenue recognition for service agreements. Contractual payments related to the sale of the project asset and assignment of the PPA are generally received up-front. Payment terms for service agreements are generally ratable over the term of the agreement. Module sales Contracts for module sales represent the sale of a completed fuel cell module at a contracted selling price. These contracts are on a per unit basis and revenue is recognized as each unit is completed and ready to ship and the performance obligation is satisfied. Payment terms for module sales are generally based on milestones achieved through the manufacturing timeline of the module. Service agreements Service agreements represent a single performance obligation whereby the Company performs all required maintenance and monitoring functions, including replacement of modules, to ensure the power platform(s) under the service agreement generate a minimum power output. To the extent the power platform(s) under service agreements do not achieve the minimum power output, certain service agreements include a performance guarantee penalty. Performance guarantee penalties represent variable consideration, which is estimated for each service agreement based on past experience, using the expected value method. The consideration for each service agreement is recognized over time using costs incurred to date relative to total estimated costs at completion to measure progress. The Company reviews its cost estimates on service agreements on an annual basis and records any changes in estimates on a cumulative catch-up basis. Loss accruals for service agreements are recognized to the extent that the estimated remaining costs to satisfy the performance obligation exceed the estimated remaining unrecognized consideration. Estimated losses are recognized in the period in which losses are identified. Payment terms for service agreements are generally ratable over the term of the agreement. Advanced Technologies contracts Advanced Technologies contracts include the promise to perform research and development services and, as such, this represents one performance obligation. Revenue from most government sponsored Advanced Technologies projects is recognized as direct costs are incurred plus allowable overhead less cost share requirements, if any. Revenue is only recognized to the extent the contracts are funded. Revenue recognition for research performed under the EMTEC Joint Development Agreement (as defined elsewhere herein) falls into the practical expedient category where revenue is recorded consistent with the amounts the Company has the right to invoice. Payments are based on costs incurred for government sponsored Advanced Technologies projects and payments under the EMTEC Joint Development Agreement are based on contractual rates for time spent and material costs incurred. Generation revenue For certain project assets where customers purchase electricity from the Company under PPAs, the Company has determined that these agreements should be accounted for as operating leases pursuant to ASC 842, Leases
Variable Interest Entities and Noncontrolling Interests	Variable Interest Entities and Noncontrolling Interests The Company has entered into tax equity financing transactions with certain participating companies for three partnerships (as further described in Note 3. “Tax Equity Financings and Investment Tax Credit Sale”) as of October 31, 2024. These transactions are structured as “partnership flips.” A “partnership flip” is a structure commonly used by tax equity investors in financing renewable energy projects. The Company has determined, under the power and benefits criterion of ASC 810, Consolidations
Sale-Leaseback Accounting	Sale-Leaseback Accounting The Company, through certain wholly-owned subsidiaries, has entered into sale-leaseback transactions for commissioned project assets where we have entered into a PPA with a customer who is both the site host and end user of the power. Due to the Company not meeting criteria to account for the transfer of the project assets as a sale since the leases include a repurchase right, sale accounting is precluded. Accordingly, the Company uses the financing method to account for these transactions. Under the financing method of accounting for a sale-leaseback, the Company does not derecognize the project assets and does not recognize as revenue any of the sale proceeds received from the lessor that contractually constitutes payment to acquire the assets subject to these arrangements. Instead, the sale proceeds received are accounted for as finance obligations and leaseback payments made by the Company are allocated between interest expense and a reduction to the finance obligation. Interest on the finance obligation is calculated using the Company’s incremental borrowing rate at the inception of the arrangement on the outstanding finance obligation. While we receive financing for the related project asset, we have not recognized revenue on the sale-leaseback transactions. Instead, revenue is recognized with respect to the related PPAs in accordance with the Company’s accounting policies for recognizing generation revenue.
Lease Accounting	Lease Accounting Right-of-use (“ROU”) assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the present value of the Company’s obligation to make lease payments arising from the lease over the lease term at the commencement date of the lease. As most of the Company’s leases do not provide an implicit rate, the Company estimated the incremental borrowing rate based on the information available at the date of adoption in determining the present value of lease payments and used the implicit rate when readily determinable. The Company determined incremental borrowing rates through market sources for secured borrowings including relevant industry rates. The Company’s operating lease ROU assets also include any lease pre-payments and exclude lease incentives. Certain of the Company’s leases include variable payments, which may vary based upon changes in facts or circumstances after the start of the lease. The Company excludes variable payments from lease ROU assets and lease liabilities to the extent not considered in-substance fixed, and instead, expenses variable payments as incurred. Variable lease expense and lease expense for short term contracts are not material components of lease expense. The Company’s leases generally have remaining lease terms of approximately 1 to 21 years, some of which include options to extend the leases. The exercise of lease renewal options is at the Company’s sole discretion and the Company’s lease ROU assets and liabilities reflect only the options the Company is reasonably certain that it will exercise. We do not have leases with residual value guarantees or similar covenants.
Service Expense Recognition	Service Expense Recognition We warranty our products for a specific period of time against manufacturing or performance defects. Our U.S. warranty is generally limited to a term of 15 months after shipment or 12 months after acceptance of our products. We accrue for estimated future warranty costs based on historical experience. We also provide for a specific accrual if there is a known issue requiring repair during the warranty period. In addition to the standard product warranty, we have entered into service agreements with certain customers to provide monitoring, maintenance and repair services for fuel cell power platforms. Under the terms of these service agreements, the power platform must meet a minimum operating output during the term. If the minimum output falls below the contract requirement, we may be subject to performance penalties or may be required to repair and/or replace the customer’s fuel cell module(s). The Company records loss accruals for service agreements when the estimated cost of future module exchanges and maintenance and monitoring activities exceeds the remaining unrecognized contract value. Estimates for future costs on service agreements are determined by a number of factors, including the estimated remaining life of the module(s), used replacement modules available and future operating plans for the power platform. Our estimates are performed on a contract by contract basis and include cost assumptions based on what we anticipate the service requirements will be to fulfill obligations for each contract. At the end of our service agreements, customers are expected to either renew the service agreement or, based on the Company’s rights to title of the module, the module will be returned to the Company as the platform is no longer being maintained.
Research and Development Costs	Research and Development Costs We perform both customer-sponsored research and development projects based on contractual agreements with customers and company-sponsored research and development projects. Costs incurred for customer-sponsored projects include manufacturing and engineering labor, applicable overhead expenses, materials to build and test prototype units and other costs associated with customer-sponsored research and development contracts. Costs incurred for customer-sponsored projects are recorded as cost of Advanced Technologies contract revenues in the Consolidated Statements of Operations and Comprehensive Loss. Costs incurred for company-sponsored research and development projects consist primarily of labor, overhead, materials to build and test prototype units and consulting fees. These costs are recorded as Research and development expenses in the Consolidated Statements of Operations and Comprehensive Loss.
Concentrations	Concentrations We contract with a concentrated number of customers for the sale of our products, for service agreements, for power purchase agreements and for Advanced Technologies contracts. For the years ended October 31, 2024, 2023 and 2022, our top customers accounted for 65%, 70% and 74%, respectively, of our total annual consolidated revenue. The percent of consolidated revenues from our top customers for the years ended October 31, 2024, 2023 and 2022, respectively, are presented below. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended October 31, ​ 2024 2023 2022 Connecticut Light and Power ​ 21 % 13 % 14 % Gyeonggi Green Energy Co., Ltd. (“GGE”) ​ 18 % — % — % Esso Nederland B.V. (“Esso”) 10 % 2 % — % ExxonMobil Technology and Engineering Company (f/k/a ExxonMobil Research and Engineering Company) (EMTEC) 8 % 8 % 8 % Ameresco/Sacramento Sewer 7 % — % — % Korea Southern Power Company (KOSPO) ​ 1 % 31 % 6 % Korea Fuel Cell Co., Ltd (KFC) ​ — % 16 % 46 % Total 65 % 70 % 74 %
Derivatives	Derivatives ​ We do not use derivatives for speculative or trading purposes. The Company has an interest rate swap that is adjusted to fair value on a quarterly basis. The estimated fair value is based on Level 2 inputs including primarily the floating Secured Overnight Financing Rate (“SOFR”) rate available to swap dealers. The valuation methodology involves comparison of (i) the sum of the present value of all quarterly variable rate payments based on a reset rate using the floating SOFR curve and (ii) the sum of the present value of all quarterly fixed rate payments on the notional amount, which is equivalent to the outstanding principal amount of the loan. ​ The Company has recorded certain natural gas purchase contracts at fair value which was the result of the net settling of certain natural gas purchases under contracts that were previously designated as normal purchase normal sale which resulted in a change to mark-to-market accounting. The fair values are adjusted on a quarterly basis. The estimated fair value is based on Level 2 inputs including future prices available to commodity brokers and risk-free rates which are based on Federal reserve yields. The valuation methodology involves utilizing the industry-convention energy swap model.
Use of Estimates	Use of Estimates The preparation of financial statements and related disclosures in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities. Estimates are used in accounting for, among other things, revenue recognition, lease right-of-use assets and liabilities, excess, slow-moving and obsolete inventories, product warranty accruals, loss accruals on service agreements, share-based compensation expense, allowance for doubtful accounts, depreciation and amortization, impairment of goodwill and in-process research and development intangible assets, impairment of long-lived assets (including project assets), valuation of derivatives and contingencies. Estimates and assumptions are reviewed periodically, and the effects of revisions are reflected in the consolidated financial statements in the period they are determined to be necessary. Due to the inherent uncertainty involved in making estimates, actual results in future periods may differ from those estimates.
Foreign Currency Translation	Foreign Currency Translation The translation of the financial statements of FCE Korea Ltd., FCES GmbH and Versa Power Systems Ltd. results in translation gains or losses, which are recorded in Accumulated other comprehensive loss within Stockholders’ equity on the accompanying Consolidated Balance Sheets. We are also subject to foreign currency transaction gains and losses as certain transactions are denominated in foreign currencies.
Recently Adopted Accounting Guidance and Recent Accounting Guidance Not Yet Effective	Recently Adopted Accounting Guidance There is no recently adopted accounting guidance applicable to the Company’s financial statements . Recent Accounting Guidance Not Yet Effective In November 2023, the Financial Accounting Standards Board (“FASB”) issued guidance to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. In addition, the guidance enhances interim disclosure requirements, clarifies circumstances in which an entity can disclose multiple segment measures of profit or loss, provides new segment disclosure requirements for entities with a single reportable segment and contains other disclosure requirements. The purpose of the guidance is to enable investors to better understand an entity’s overall performance and assess potential future cash flows. The guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. We are currently evaluating the impact that the new guidance will have on our consolidated financial statements. ​ In December 2023, the FASB issued guidance to enhance income tax disclosures by providing information to better assess how an entity’s operations, related tax risks, tax planning and operational opportunities affect its tax rate and prospects for future cash flows. Additional disclosures will be required to the annual effective tax rate reconciliation including specific categories and further disaggregated reconciling items that meet the quantitative threshold. Additionally, disclosures will be required relating to income tax expense and payments made to federal, state, local and foreign jurisdictions. This guidance is effective for fiscal years and interim periods beginning after December 15, 2024. We are currently evaluating the impact that the new guidance will have on our consolidated financial statements. ​ In November 2024, the FASB issued new guidance which requires enhanced disclosure of specified categories of expenses included in certain expense captions presented on the face of the income statement. This guidance will be effective for fiscal years beginning after December 15, 2026 and for interim periods beginning after December 15, 2027. The Company is currently evaluating the new guidance to determine its adoption approach and the impact on the presentation and disclosures of its consolidated statement of operations and comprehensive loss. The Company anticipates its processes will be enhanced to address the disaggregation and disclosure requirements, though it does not expect adoption to impact its overall results from operations.

Nature of Business, Basis of _3

Nature of Business, Basis of Presentation and Significant Accounting Policies (Tables)	12 Months Ended
	Oct. 31, 2024
Nature of Business, Basis of Presentation and Significant Accounting Policies
Schedule of percent of consolidated revenues	The percent of consolidated revenues from our top customers for the years ended October 31, 2024, 2023 and 2022, respectively, are presented below. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended October 31, ​ 2024 2023 2022 Connecticut Light and Power ​ 21 % 13 % 14 % Gyeonggi Green Energy Co., Ltd. (“GGE”) ​ 18 % — % — % Esso Nederland B.V. (“Esso”) 10 % 2 % — % ExxonMobil Technology and Engineering Company (f/k/a ExxonMobil Research and Engineering Company) (EMTEC) 8 % 8 % 8 % Ameresco/Sacramento Sewer 7 % — % — % Korea Southern Power Company (KOSPO) ​ 1 % 31 % 6 % Korea Fuel Cell Co., Ltd (KFC) ​ — % 16 % 46 % Total 65 % 70 % 74 %

Investments - Short-Term (Table

Investments - Short-Term (Tables)	12 Months Ended
	Oct. 31, 2024
Investments - Short-Term
Schedule of Investments in Held-to-Maturity Securities	The following table summarizes the amortized cost basis and fair value (based on quoted market prices) as of October 31, 2024 (in thousands). ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortized ​ Gross unrealized ​ Gross unrealized ​ ​ cost gains ​ losses Fair value U.S. Treasury Securities ​ ​ ​ ​ ​ ​ ​ ​ ​ As of October 31, 2024 ​ $ 109,123 $ 2 $ - $ 109,125 As of October 31, 2023 ​ $ 103,760 $ 1 $ - $ 103,761

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Oct. 31, 2024
Inventories
Schedule of Inventories	Inventories (short and long-term) as of October 31, 2024 and 2023 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ 2024 2023 Raw materials ​ $ 35,989 ​ $ 36,200 Work-in-process (1) ​ ​ 80,457 ​ ​ 55,585 Inventories ​ ​ 116,446 ​ ​ 91,785 Inventories – current ​ ​ (113,703) ​ ​ (84,456) Inventories – long-term (2) ​ $ 2,743 ​ $ 7,329 (1) Work-in-process includes the standard components of inventory used to build the typical modules or module components that are intended to be used in future project asset construction or power platform orders or for use under the Company’s service agreements. (2) Long-term inventory includes modules that are contractually required to be segregated for use as replacement modules for a specific project asset .

Project Assets (Tables)

Project Assets (Tables)	12 Months Ended
	Oct. 31, 2024
Project Assets
Summary of Project Assets	Project assets as of October 31, 2024 and 2023 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ Estimated ​ 2024 2023 Useful Life Project Assets – Operating ​ $ 308,503 ​ $ 213,753 ​ 4-20 years Accumulated depreciation ​ ​ (66,542) ​ ​ (46,263) ​ ​ Project Assets – Operating, net ​ ​ 241,961 ​ ​ 167,490 ​ ​ Project Assets – Construction in progress ​ ​ 170 ​ ​ 90,576 ​ 7-20 years Project Assets, net ​ $ 242,131 ​ $ 258,066 ​ ​

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Oct. 31, 2024
Property, Plant and Equipment.
Schedule of property plant and equipment	Property, plant and equipment as of October 31, 2024 and 2023 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ Estimated ​ ​ 2024 ​ 2023 ​ Useful Life Land ​ $ 524 ​ $ 524 ​ — Building and improvements ​ 26,581 ​ 21,430 10‑26 years Machinery, equipment and software ​ 144,242 ​ 136,554 3‑8 years Furniture and fixtures ​ 5,451 ​ 5,211 10 years Construction in progress ​ 68,588 ​ 33,950 — ​ ​ 245,386 ​ 197,669 ​ ​ Accumulated depreciation ​ (114,700) ​ (108,001) Property, plant and equipment, net ​ $ 130,686 ​ $ 89,668

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Oct. 31, 2024
Goodwill and Intangible Assets
Summary of intangible assets	The following tables summarize the Company’s intangible assets as of October 31, 2024 and 2023 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of October 31, 2024 Gross Amount Accumulated Amortization Net Amount In-Process Research and Development ​ $ 9,592 ​ $ - ​ $ 9,592 Bridgeport PPA ​ ​ 12,320 ​ ​ (7,133) ​ ​ 5,187 Total ​ $ 21,912 ​ $ (7,133) ​ $ 14,779 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of October 31, 2023 Gross Amount Accumulated Amortization Net Amount In-Process Research and Development ​ $ 9,592 ​ $ - ​ $ 9,592 Bridgeport PPA ​ ​ 12,320 ​ ​ (5,836) ​ ​ 6,484 Total ​ $ 21,912 ​ $ (5,836) ​ $ 16,076

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Oct. 31, 2024
Accrued Liabilities
Schedule of accrued liabilities	Accrued liabilities as of October 31, 2024 and 2023 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ 2024 2023 Accrued payroll and employee benefits (1) ​ $ 9,808 ​ $ 7,752 Consideration payable to a customer (2) ​ ​ 2,515 ​ ​ 3,958 Accrued service agreement and PPA costs (3) ​ ​ 10,574 ​ ​ 10,742 Accrued legal, taxes, professional and other ​ ​ 5,230 ​ ​ 3,861 Accrued severance costs (4) ​ ​ 2,235 ​ ​ - Accrued liabilities ​ $ 30,362 ​ $ 26,313 (1) The balance in this account represents accrued payroll, payroll taxes and accrued bonus for both periods. The increase in the account balance relates to an increase in accrued bonus as of October 31, 2024. (2) The balance represents the net amount due to Toyota as an accrued liability which will be reduced over time based on the performance under the terms of the Toyota HPPA. (3) Accrued service agreement costs include loss accruals on service contracts of $9.0 million as of October 31, 2024, which decreased from $9.5 million as of October 31, 2023. The decrease is the result of changes in estimates regarding timing of future module exchanges and future module replacement costs. The accruals for performance guarantees on service agreements and PPAs increased from $1.2 million as of October 31, 2023 to $1.5 million as of October 31, 2024. (4) Accrued severance costs represent amounts accrued relating to restructuring activities and workforce reductions that occurred in September 2024. Refer to Note 4. “Restructuring” for more information about the restructuring.

Leases (Tables)

Leases (Tables)	12 Months Ended
	Oct. 31, 2024
Leases
Summary of undiscounted maturities of operating lease and finance lease liabilities	As of October 31, 2024, undiscounted maturities of operating lease liabilities are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ Operating Leases Due Year 1 ​ $ 1,361 ​ Due Year 2 ​ ​ 1,374 ​ Due Year 3 ​ ​ 1,407 ​ Due Year 4 ​ ​ 1,375 ​ Due Year 5 ​ ​ 795 ​ Thereafter ​ ​ 11,923 ​ Total undiscounted lease payments ​ ​ 18,235 ​ Less imputed interest ​ ​ (8,534) ​ Total discounted lease payments ​ $ 9,701 ​ ​

Debt (Tables)

Debt (Tables)	12 Months Ended
	Oct. 31, 2024
Debt
Schedule of Debt	Debt as of October 31, 2024 and 2023 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ 2024 2023 Export-Import Bank of the United States Financing Facility ​ $ 10,104 ​ $ — Liberty Bank Term Loan Agreement (Derby Senior Back Leverage Loan Facility) ​ ​ 5,825 ​ ​ — Connecticut Green Bank Term Loan Agreement (Derby Senior Back Leverage Loan Facility) ​ ​ 2,689 ​ ​ — Connecticut Green Bank Loan (Derby Subordinated Back Leverage Loan Facility) ​ ​ 3,500 ​ ​ — Connecticut Green Bank Loan (Groton Subordinated Back Leverage Loan Facility) ​ ​ 8,000 ​ ​ 8,000 Liberty Bank Term Loan Agreement (Groton Senior Back Leverage Loan Facility) ​ ​ 5,437 ​ ​ 5,876 Amalgamated Bank Loan (Groton Senior Back Leverage Loan Facility) ​ ​ 5,420 ​ ​ 5,873 Finance obligation for sale-leaseback transactions ​ ​ 18,811 ​ ​ 18,814 State of Connecticut Loan ​ ​ 6,024 ​ ​ 6,908 Finance lease obligations ​ ​ — ​ ​ 12 OpCo Financing Facility ​ ​ 70,067 ​ ​ 77,510 Deferred finance costs ​ ​ (4,215) ​ ​ (3,526) Total debt and finance obligations ​ ​ 131,662 ​ ​ 119,467 Current portion of long-term debt and finance obligations ​ ​ (15,924) ​ ​ (10,067) Long-term debt and finance obligations ​ $ 115,738 ​ $ 109,400
Aggregate Annual Principal Payments under Loan Agreements and Finance Lease Obligations	Aggregate annual principal payments under our loan agreements, finance obligation, and finance lease obligations for the years subsequent to October 31, 2024 are as follows (in thousands): ​ ​ ​ ​ ​ Year 1 $ 14,440 Year 2 ​ 14,759 Year 3 ​ 10,930 Year 4 ​ 12,237 Year 5 ​ 11,305 Thereafter (1) ​ 61,659 ​ ​ $ 125,330 (1) The annual principal payments included above only include sale-leaseback payments whereas the difference between debt outstanding as of October 31, 2024 and the annual principal payments represent accreted interest and amounts included in the finance obligation that exceed required principal payments.

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Oct. 31, 2024
Segment Information
Revenues By Geographic Area	Revenues, by geographic location (based on the customer’s ordering location) for the years ended October 31, 2024, 2023 and 2022 were as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 2022 United States ​ $ 86,962 ​ $ 63,289 ​ $ 60,290 South Korea ​ 22,836 ​ 58,432 ​ 68,341 Europe ​ 1,919 ​ 1,673 ​ 1,853 Canada ​ 415 ​ ​ — ​ ​ — Total ​ $ 112,132 ​ $ 123,394 ​ $ 130,484

Benefit Plans (Tables)

Benefit Plans (Tables)	12 Months Ended
	Oct. 31, 2024
Benefit Plans
Schedule of Share-Based Compensation Reflected in Consolidated Statement of Operations and Comprehensive Loss	Share-based compensation was reflected in the Consolidated Statements of Operations and Comprehensive Loss as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended October 31, ​ ​ 2024 2023 ​ 2022 ​ Cost of revenues ​ $ 1,460 ​ $ 1,502 ​ $ 706 ​ Administrative and selling expense ​ ​ 8,583 ​ ​ 8,657 ​ ​ 5,418 ​ Research and development expense ​ ​ 1,428 ​ ​ 1,429 ​ ​ 456 ​ ​ ​ $ 11,471 ​ $ 11,588 ​ $ 6,580 ​
Summary of RSU Activity	The following table summarizes our RSU and PSU activity for the year ended October 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ Restricted Stock Units ​ Shares Weighted-Average Fair Value Outstanding as of October 31, 2023 ​ ​ 217,947 ​ $ 151.89 Granted - time-vesting RSUs ​ ​ 313,883 ​ ​ 38.13 Granted - PSUs ​ ​ 109,146 ​ ​ 48.90 Vested ​ ​ (76,420) ​ ​ 210.12 Forfeited ​ ​ (47,995) ​ ​ 67.96 Outstanding as of October 31, 2024 ​ ​ 516,561 ​ $ 64.53

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Oct. 31, 2024
Income Taxes
Schedule of Components of Loss Before Income Taxes	The components of loss before income taxes for the years ended October 31, 2024, 2023, and 2022 were as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 2022 U.S. ​ $ (140,713) ​ $ (95,910) ​ $ (145,439) Foreign ​ (16,040) ​ (11,565) ​ (974) Loss before income taxes ​ $ (156,753) ​ $ (107,475) ​ $ (146,413)
Schedule of Reconciliation of Federal Statutory Income Tax Rate To Effective Income Tax Rate	The reconciliation of the federal statutory income tax rate to our effective income tax rate for the years ended October 31, 2024, 2023 and 2022 was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 2022 Statutory federal income tax rate (21.0) % (21.0) % (21.0) % Increase (decrease) in income taxes resulting from: ​ ​ ​ ​ ​ ​ State taxes, net of Federal benefits (4.4) % (3.2) % (3.6) % Foreign withholding tax 0.1 % 0.5 % 0.6 % Net operating loss expiration, impairment and true-ups (1.1) % 6.1 % 8.7 % Nondeductible expenditures 0.2 % 2.1 % 1.4 % Change in tax rates (0.4) % 2.8 % 0.3 % Other, net 0.3 % 0.6 % 0.7 % Deferred only adjustment (0.4) % (0.1) % (0.1) % Valuation allowance 26.8 % 12.7 % 13.6 % Effective income tax rate 0.1 % 0.5 % 0.6 %
Schedule of Deferred Tax Assets and Liabilities	Our deferred tax assets and liabilities consisted of the following as of October 31, 2024 and 2023 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 Deferred tax assets: ​ ​ Compensation and benefit accruals ​ $ 7,344 ​ $ 6,026 Bad debt and other allowances ​ 2,695 ​ 1,945 Capital loss and tax credit carry-forwards ​ 16,296 ​ 14,701 Net operating losses (domestic and foreign) ​ 170,780 ​ 139,900 Deferred license revenue ​ 871 ​ 1,148 Accumulated depreciation ​ 15,969 ​ 14,051 Grant revenue ​ 210 ​ 323 Excess business interest ​ 5,860 ​ 6,406 Operating lease liabilities ​ 1,840 ​ 1,879 Capitalized research and development ​ ​ 18,305 ​ ​ 9,729 Mark-to-market ​ ​ 1,702 ​ ​ 987 Other ​ ​ 150 ​ ​ 4 Gross deferred tax assets: ​ 242,022 ​ 197,099 Valuation allowance ​ (228,139) ​ (193,477) Deferred tax assets after valuation allowance ​ 13,883 ​ 3,622 Deferred tax liability: ​ ​ ​ ​ Net loss attributable to noncontrolling interests ​ ​ (7,567) ​ ​ — In process research and development ​ (2,322) ​ (2,293) Right of use assets ​ (1,556) ​ (1,600) Other ​ ​ (2,745) ​ ​ (9) Net deferred tax liability ​ $ (307) ​ $ (280)

Loss Per Share (Tables)

Loss Per Share (Tables)	12 Months Ended
	Oct. 31, 2024
Loss Per Share
Schedule of Calculation of Basic and Diluted Loss Per Share	The calculation of basic and diluted EPS for the years ended October 31, 2024, 2023 and 2022 was as follows (amounts in thousands, except share and per share amounts): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended October 31, ​ ​ 2024 ​ 2023 ​ 2022 Numerator ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss attributable to FuelCell Energy, Inc. $ (126,009) ​ $ (107,568) ​ $ (142,722) ​ Series B preferred stock dividends ​ (3,200) ​ ​ (3,200) ​ ​ (3,200) ​ Net loss attributable to common stockholders $ (129,209) ​ $ (110,768) ​ $ (145,922) ​ Denominator ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding – basic ​ 16,505,257 ​ ​ 13,991,593 ​ ​ 12,771,305 ​ Effect of dilutive securities (1) ​ - ​ ​ - ​ ​ — ​ Weighted average common shares outstanding – diluted ​ 16,505,257 ​ ​ 13,991,593 ​ ​ 12,771,305 ​ Net loss to common stockholders per share – basic $ (7.83) ​ $ (7.92) ​ $ (11.43) ​ Net loss to common stockholders per share – diluted (1) $ (7.83) ​ $ (7.92) ​ $ (11.43) ​ (1) Due to the net loss to common stockholders in each of the years presented above, diluted earnings per share was computed without consideration to potentially dilutive instruments as their inclusion would have been antidilutive. As of October 31, 2024, 2023 and 2022, potentially dilutive securities excluded from the diluted loss per share calculation are as follows:
Schedule of Potentially Dilutive Securities Excluded from the Diluted Loss Per Share Calculation	As of October 31, 2024, 2023 and 2022, potentially dilutive securities excluded from the diluted loss per share calculation are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ October 31, ​ 2024 2023 ​ 2022 Outstanding options to purchase common stock ​ ​ 574 ​ ​ 610 ​ ​ 674 Unvested Restricted Stock Units ​ ​ 516,561 ​ ​ 218,105 ​ ​ 84,029 5% Series B Cumulative Convertible Perpetual Preferred Stock ​ ​ 1,261 ​ ​ 1,261 ​ ​ 1,261 Total potentially dilutive securities ​ ​ 518,396 ​ ​ 219,976 ​ ​ 85,965 ​

Restricted Cash (Tables)

Restricted Cash (Tables)	12 Months Ended
	Oct. 31, 2024
Restricted Cash.
Summary of Allocation of Restricted Cash	The allocation of restricted cash is as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 31, ​ October 31, ​ 2024 2023 Cash Restricted for Outstanding Letters of Credit (1) ​ $ 14,152 ​ $ 14,152 Cash Restricted for Crestmark Sale-Leaseback Transactions ​ ​ 2,908 ​ ​ 2,901 Debt Service and Performance Reserves related to OpCo Financing Facility ​ ​ 24,721 ​ ​ 19,698 Debt Service and Performance Reserves related to the Senior and Subordinated Back Leverage Loan Facilities ​ ​ 12,869 ​ ​ 9,294 Other ​ ​ 6,100 ​ ​ 3,579 Total Restricted Cash ​ ​ 60,750 ​ ​ 49,624 Restricted Cash and Cash Equivalents – Short-Term (2) ​ ​ (12,161) ​ ​ (5,159) Restricted Cash and Cash Equivalents – Long-Term ​ $ 48,589 ​ $ 44,465 (1) Letters of credit outstanding as of October 31, 2024 expire on various dates through October 2029. (2) Short-term restricted cash and cash equivalents are amounts expected to be released and categorized as unrestricted cash within twelve months of the balance sheet date.

Supplemental Cash Flow Inform_2

Supplemental Cash Flow Information (Tables)	12 Months Ended
	Oct. 31, 2024
Supplemental Cash Flow Information
Schedule of Cash Flow, Supplemental Disclosures	The following represents supplemental cash flow information (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended October 31, ​ 2024 2023 2022 Cash interest paid ​ $ 6,796 ​ $ 3,088 ​ $ 1,556 Income taxes paid ​ 16 ​ 6 ​ 2 Noncash financing and investing activity: ​ ​ ​ ​ ​ Noncash reclassifications between inventory and project assets ​ 4,586 ​ 1,987 ​ 1,260 Noncash reclassifications from inventory to fixed assets ​ ​ — ​ ​ — ​ ​ 1,552 Noncash reclassifications from other assets to project assets ​ ​ — ​ ​ — ​ ​ 2,375 Director stock compensation ​ 159 ​ 225 ​ 305 Accrued noncontrolling interest distribution ​ ​ — ​ ​ 148 ​ ​ — Addition of operating lease liabilities ​ 395 ​ 1,952 ​ — Addition of operating lease right-of-use assets ​ 395 ​ 1,952 ​ — Noncash reduction in basis of project assets ​ — ​ 6,330 ​ — Accrued purchase of fixed assets, cash paid to be paid in subsequent period ​ 2,958 ​ 1,646 ​ 4,396 Accrued purchase of project assets, cash to be paid in subsequent period ​ 269 ​ 4,515 ​ 6,444 ​

Nature of Business, Basis of _4

Nature of Business, Basis of Presentation and Significant Accounting Policies - Additional Information (Details)								3 Months Ended		12 Months Ended
	Dec. 12, 2024 USD ($)	Nov. 08, 2024 shares	Oct. 31, 2024 USD ($) MW shares	Apr. 10, 2024 USD ($)	Dec. 16, 2022 MW	Dec. 15, 2022 MW	Jul. 12, 2022 shares	Jan. 31, 2024 MW	Oct. 31, 2023 USD ($) MW shares	Oct. 31, 2024 USD ($) item MW shares	Oct. 31, 2023 USD ($) shares	Oct. 31, 2022 USD ($) shares	Nov. 07, 2024 shares	Apr. 25, 2024 USD ($)	Oct. 11, 2023 shares	Oct. 10, 2023 shares	Oct. 31, 2021 shares
Nature of Business and Basis of Presentation
Cash and cash equivalents, unrestricted			$ 148,133,000						$ 249,952,000	$ 148,133,000	$ 249,952,000	$ 458,055,000
Investments - short-term			109,123,000						103,760,000	109,123,000	103,760,000
Allowance for doubtful accounts or credit losses			$ 0						$ 0	0	0
Impairment of goodwill										$ 0	$ 0	$ 0
Percentage of electricity output provided to customers										100%
Common stock, shares outstanding (in shares) | shares			20,375,932						15,020,872	20,375,932	15,020,872
Common stock, shares authorized (in shares) | shares			1,000,000,000						1,000,000,000	1,000,000,000	1,000,000,000				1,000,000,000	500,000,000
Extended product warranty description										We warranty our products for a specific period of time against manufacturing or performance defects. Our U.S. warranty is generally limited to a term of 15 months after shipment or 12 months after acceptance of our products.
Extended product warranty period after shipment										15 months
Extended product warranty period after acceptance of products										12 months
Number of fuel cell power plants, tax equity financing transaction									2
U.S. Treasury Securities
Nature of Business and Basis of Presentation
Investments - short-term			$ 109,100,000						$ 103,800,000	$ 109,100,000	$ 103,800,000
Derby Senior Back Leverage Loan Facility and Derby Subordinated Back Leverage Loan Facility
Nature of Business and Basis of Presentation
Debt instrument, face amount														$ 12,800,000
EXIM
Nature of Business and Basis of Presentation
Number of fuel cells | item										42
Capacity of fuel cell | MW			1.4							1.4
Proceeds from long-term lines of credit			$ 10,100,000							$ 9,200,000
Common Stock
Nature of Business and Basis of Presentation
Shares sold during the period | shares										5,302,378	1,477,361	1,279,897
Common stock, shares outstanding (in shares) | shares			20,375,932						15,020,872	20,375,932	15,020,872	13,518,743					12,220,600
Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canacord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC | Amended Open Market Sales Agreement
Nature of Business and Basis of Presentation
Shares sold during the period | shares										5,300,000
Gross proceeds from issuance of common stock to date under the amended sales agreement			$ 95,100,000							$ 95,100,000
Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canacord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC | Amended Open Market Sales Agreement | Common Stock
Nature of Business and Basis of Presentation
Aggregate offering price				$ 300,000,000
Shares sold during the period | shares			5,300,000
Gross proceeds from issuance of common stock to date under the amended sales agreement			$ 95,100,000						$ 99,700,000	95,100,000	$ 99,700,000
Franklin Park Tax Equity Financing Transaction [Member]
Nature of Business and Basis of Presentation
Tax equity financing commitment									30,200,000		30,200,000
Tax equity financing transaction, commitment amount received									$ 9,100,000	$ 21,100,000
Closing costs											$ 1,800,000
Derby Project 14.0 Mega Watt
Nature of Business and Basis of Presentation
Capacity of plant | MW									14	14
Derby Project 2.8 Mega Watt
Nature of Business and Basis of Presentation
Capacity of plant | MW									2.8	2.8
Groton Project
Nature of Business and Basis of Presentation
Capacity of plant | MW					6	7.4
Capacity of plant due to Technical Improvement Plan | MW								7.4
Contribution received under the Technical Improvement Plan										$ 4,000,000
Subsequent Event
Nature of Business and Basis of Presentation
Reverse stock split, conversion ratio		0.033
Common stock, shares outstanding (in shares) | shares		20,375,932											611,278,662
Common stock, shares authorized (in shares) | shares		1,000,000,000
Preferred shares authorized | shares		250,000
Subsequent Event | Groton Project
Nature of Business and Basis of Presentation
Tax equity financing transaction, commitment amount received	$ 4,000,000
Maximum
Nature of Business and Basis of Presentation
Operating and finance lease, remaining lease term										21 years
Maximum | Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canacord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC | Amended Open Market Sales Agreement | Common Stock
Nature of Business and Basis of Presentation
Shares sold during the period | shares							3,200,000
Minimum
Nature of Business and Basis of Presentation
Operating and finance lease, remaining lease term										1 year

Nature of Business, Basis of _5

Nature of Business, Basis of Presentation and Significant Accounting Policies - Percent of Customer Consolidated Revenues (Details) - Revenue Benchmark - Customer Concentration Risk	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Connecticut Light And Power
Nature Of Business And Basis Of Presentation [Line Items]
Significant customer revenue percentage	21%	13%	14%
Gyeonggi Green Energy Co., Ltd. ("GGE")
Nature Of Business And Basis Of Presentation [Line Items]
Significant customer revenue percentage	18%
Esso Nederland B.V. ("Esso")
Nature Of Business And Basis Of Presentation [Line Items]
Significant customer revenue percentage	10%	2%
ExxonMobil Technology and Engineering Company (f/k/a ExxonMobil Research and Engineering Company) (EMTEC)
Nature Of Business And Basis Of Presentation [Line Items]
Significant customer revenue percentage	8%	8%	8%
Ameresco/Sacramento Sewer
Nature Of Business And Basis Of Presentation [Line Items]
Significant customer revenue percentage	7%
Korea Southern Power Company (KOSPO)
Nature Of Business And Basis Of Presentation [Line Items]
Significant customer revenue percentage	1%	31%	6%
Korea Fuel Cell Co., Ltd (KFC)
Nature Of Business And Basis Of Presentation [Line Items]
Significant customer revenue percentage		16%	46%
Top Customers
Nature Of Business And Basis Of Presentation [Line Items]
Significant customer revenue percentage	65%	70%	74%

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Details) $ in Thousands

1 Months Ended

3 Months Ended

12 Months Ended

May 28, 2024 USD ($)

May 28, 2024 USD ($)

May 28, 2024 USD ($) item

May 28, 2024 USD ($) MW

Dec. 20, 2021 USD ($) item

Oct. 29, 2021 USD ($)

Oct. 31, 2019 USD ($)

May 31, 2023 USD ($)

Apr. 30, 2022 USD ($)

Oct. 31, 2024 USD ($)

Oct. 31, 2023 USD ($)

Oct. 31, 2022 USD ($) item

Jul. 31, 2024 item

Mar. 31, 2024 USD ($)

Jan. 31, 2024 USD ($)

Aug. 25, 2023 USD ($)

Aug. 24, 2023 USD ($)

Jul. 31, 2023 item

Dec. 19, 2022 USD ($)

Dec. 18, 2022 USD ($)

Apr. 29, 2022 USD ($)

Apr. 28, 2022 USD ($)

Revenue Recognition

Contract asset

$ 65,100

$ 42,100

Contract asset, long-term

28,300

25,800

Contract liability

7,200

3,100

Consideration payable

6,300

Consideration payable, long term

6,000

Sale of investment tax credit

6,300

Revenues

112,132

123,394

$ 130,484

Amount of long-term service agreement

$ 159,600

$ 159,600

$ 159,600

$ 159,600

Research and development expenses

55,404

61,021

34,529

Accounts receivable from contract assets

16,000

12,900

Kfc And Posco international Company

Revenue Recognition

Revenues

10,500

Variable consideration

13,100

POSCO Energy Settlement Agreement

Revenue Recognition

Revenues

9,100

Settlement agreement variable consideration from contract with customer

13,100

$ 13,100

Settlement agreement number of module units sold | item

20

20

Option to purchase additional warranty module units | item

14

Number of modules | item

2

Option to purchase warranty module units | item

20

Stand alone selling price per sale module

3,000

Number of additional modules expired without exercised | item

14

Modules units, order placed | item

20

Stand alone selling price per warranty module

$ 650

Extended warranty term

7 years

Toyota Investment Tax Credit Sale

Revenue Recognition

Consideration payable

6,000

Consideration payable, long term

$ 4,500

Hydrogen production and power purchase agreement

20 years

EMTEC Joint Development Agreement

Revenue Recognition

Contract liability

$ 11,600

Revenues

$ 2,500

$ 1,700

300

Research costs reimbursement amount

$ 67,000

$ 60,000

$ 60,000

$ 50,000

$ 50,000

$ 45,000

Milestone payment received

$ 5,000

Milestone based payments

$ 5,000

Research and development expenses

$ 45,000

Investment Amount

$ 5,000

Amendment No 5 to EMTEC Joint Development Agreement

Revenue Recognition

Minimum expected annual budget for the anticipated work through the remaining term of agreement

$ 10,000

Long Term Service Agreement | Posco Energy | Noeul

Revenue Recognition

Number of modules transfer | item

16

Long Term Service Agreement | Kfc And Posco international Company | Noeul

Revenue Recognition

Number of modules transfer | item

16

GGE

Revenue Recognition

Capacity of plant | MW

58.8

Number of plants | item

21

Number of cells per plant | item

2

Number of fuel cells

42,000

42

Capacity of fuel cell | MW

1.4

Long term service agreement term

7 years

Rotterdam Project | EMTEC Joint Development Agreement

Revenue Recognition

Investments

5,000

Remaining balance

2,500

Investment Amount

5,000

Maximum | Amendment No 5 to EMTEC Joint Development Agreement

Revenue Recognition

CO2 capture annual basis | item

250,000

Service

Revenue Recognition

Revenues

9,969

49,084

12,786

Amount of revenue recognized

1,900

Generation

Revenue Recognition

Revenues

49,975

37,508

36,186

Remaining performance obligations

$ 172,400

Generation | Maximum

Revenue Recognition

Revenue performance obligation expected timing of satisfaction

20 years

Generation | Minimum

Revenue Recognition

Revenue performance obligation expected timing of satisfaction

19 years

Advanced Technologies

Revenue Recognition

Revenues

$ 26,513

17,213

21,512

Remaining performance obligations

$ 9,600

Advanced Technologies | Maximum

Revenue Recognition

Revenue performance obligation expected timing of satisfaction

2 years

Product

Revenue Recognition

Revenues

$ 25,675

$ 19,589

$ 60,000

Amount of revenue recognized

18,000

Remaining performance obligations

111,300

Service Agreements | Service

Revenue Recognition

Remaining performance obligations

$ 389,000

Service Agreements | Service | Maximum

Revenue Recognition

Revenue performance obligation expected timing of satisfaction

15 years

Service Agreements | Service | Minimum

Revenue Recognition

Revenue performance obligation expected timing of satisfaction

3 years

Tax Equity Financings and Inv_2

Tax Equity Financings and Investment Tax Credit Sale (Details)

1 Months Ended

3 Months Ended

12 Months Ended

24 Months Ended

Dec. 12, 2024 USD ($)

Dec. 31, 2023 USD ($)

Dec. 16, 2022 USD ($) MW

Dec. 15, 2022 MW

Oct. 04, 2022 MW

Sep. 06, 2022 USD ($)

Jul. 07, 2022 USD ($)

Dec. 13, 2021 USD ($)

Aug. 04, 2021 USD ($)

Nov. 30, 2021 USD ($) MW

Aug. 31, 2021 USD ($) MW

Jan. 31, 2024 MW

Oct. 31, 2023 USD ($) MW

Apr. 30, 2022 USD ($)

Oct. 31, 2024 USD ($) MW

Oct. 31, 2023 USD ($) Plant MW

Oct. 31, 2022 USD ($)

Oct. 31, 2023 USD ($)

Jan. 31, 2022 USD ($)

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Number of fuel cell power plants, tax equity financing transaction

2

Net income (loss) attributable to noncontrolling interests

$ (30,769,000)

$ (488,000)

$ (4,510,000)

Consideration payable to a customer

$ 3,958,000

$ 2,515,000

3,958,000

$ 3,958,000

Derby Project 14.0 Mega Watt

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Capacity of plant | MW

14

14

Derby Project 2.8 Mega Watt

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Capacity of plant | MW

2.8

2.8

Derby Project

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Net income (loss) attributable to noncontrolling interests

$ (28,300,000)

Groton Project

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Capacity of plant | MW

6

7.4

Net income (loss) attributable to noncontrolling interests

3,500,000

$ 2,500,000

0

Amount of distribution

100,000

0

Payment of amendment fee

$ 1,200,000

Capacity of plant due to Technical Improvement Plan | MW

7.4

Contribution received under the Technical Improvement Plan

$ 4,000,000

Percentage of cash and tax allocations to be received

95%

Tax equity financing transactions with Franklin Park

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Number of fuel cell power plants, tax equity financing transaction | Plant

2

Tax equity financing commitment

$ 30,200,000

$ 30,200,000

$ 30,200,000

Tax equity financing transaction, commitment amount received

$ 21,100,000

9,100,000

Closing costs

$ 1,800,000

Tax equity financing transactions with Franklin Park | Derby Project 14.0 Mega Watt

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Capacity of plant | MW

14

Tax equity financing transactions with Franklin Park | Derby Project 2.8 Mega Watt

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Capacity of plant | MW

2.8

Tax equity financing transactions with Franklin Park | Derby Project

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Amount of distribution

$ 1,000,000

Percentage of cash and tax allocations to be received

95%

East West Bank

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Capacity of plant | MW

7.4

Tax equity financing commitment

$ 12,000,000

$ 15,000,000

Tax equity financing, Aggregate fee

500,000

Closing costs

$ 800,000

Initial draw

3,000,000

Remaining amount of draw

$ 12,000,000

East West Bank | Groton Project

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Amount of distribution

$ 0

$ 0

Tax equity financing, Aggregate fee

$ 500,000

REI Partnership Flip Transaction

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Capacity of plant | MW

7.4

Net income (loss) attributable to noncontrolling interests

$ 900,000

2,000,000

(4,500,000)

Tax equity financing commitment

$ 12,400,000

$ 11,900,000

Closing costs

$ 400,000

Amount of Refund

$ 500,000

Percentage of annual interest rate

2.73%

Initial draw

$ 3,200,000

Remaining amount of draw

$ 9,200,000

Legal and advisory fees

400,000

Percentage of cash and tax allocations to be received

95%

Percentage of amount payable

10.30%

REI Partnership Flip Transaction | LIPA Yaphank Project

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Amount of distribution

$ 600,000

$ 0

$ 300,000

Toyota Investment Tax Credit Sale | REI

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Project's qualified ITCs

$ 8,400,000

Purchase amount of ITCs

7,100,000

Eligible capital expenditure ITC rate per $1 purchased ITCs

0.85

Transaction costs

400,000

Consideration payable to a customer

$ 6,300,000

$ 6,000,000

Subsequent Event | Groton Project

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Tax equity financing transaction, commitment amount received

$ 4,000,000

First Anniversary of Project Achieving Commercial Operations | East West Bank

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Tax equity financing commitment, Contributions

$ 4,000,000

$ 4,000,000

Second Anniversary of Project Achieving Commercial Operations | East West Bank

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Tax equity financing commitment, Contributions

4,000,000

Third Anniversary of Project Achieving Commercial Operations | East West Bank

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Tax equity financing commitment, Contributions

$ 4,000,000

Maximum | East West Bank | Groton Project

Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]

Capacity of plant | MW

7.4

Restructuring (Details)

Restructuring (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Sep. 05, 2024
Restructuring
Percentage of global workforce reduced in restructuring		4%
Restructuring expense relating to eliminated positions	$ 2,562
Restructuring expense paid	$ 300

Investments - Short-Term (Detai

Investments - Short-Term (Details) - U.S. Treasury Securities - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Investments in United States Treasury Securities
Amortized cost	$ 109,123	$ 103,760
Gross unrealized gains	2	1
Fair value	$ 109,125	$ 103,761
Weighted average yield to maturity	4.78%	5.45%

Inventories - Components of Inv

Inventories - Components of Inventories (Details) - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Inventories
Raw materials	$ 35,989	$ 36,200
Work-in-process	80,457	55,585
Inventories	116,446	91,785
Inventories - current	(113,703)	(84,456)
Inventories - long-term	$ 2,743	$ 7,329

Project Assets - Summary of Pro

Project Assets - Summary of Project Assets (Details) - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Project Assets
Accumulated depreciation	$ (66,542)	$ (46,263)
Project Assets, net	242,131	258,066
Project Assets - Operating
Project Assets
Project Assets, gross	308,503	213,753
Project Assets - Operating, net	$ 241,961	167,490
Project Assets - Operating | Minimum
Project Assets
Project assets estimated useful life	4 years
Project Assets - Operating | Maximum
Project Assets
Project assets estimated useful life	20 years
Project Assets - Construction in progress
Project Assets
Project Assets, gross	$ 170	$ 90,576
Project Assets - Construction in progress | Minimum
Project Assets
Project assets estimated useful life	7 years
Project Assets - Construction in progress | Maximum
Project Assets
Project assets estimated useful life	20 years
Project Assets BOP And Site Construction
Project Assets
Project assets estimated useful life	20 years
Project Assets Modules | Minimum
Project Assets
Project assets estimated useful life	4 years
Project Assets Modules | Maximum
Project Assets
Project assets estimated useful life	7 years

Project Assets - Additional Inf

Project Assets - Additional Information (Details) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2022 MW	Oct. 31, 2024 USD ($) item kW MW	Oct. 31, 2023 USD ($) item	Oct. 31, 2022 USD ($)
Project Assets
Number of project assets | item		12	9
Long-term project assets construction in progress		$ 0.2	$ 90.6
Impairment charges			2.4
Project asset depreciation		26.9	19	$ 14.2
Hartford
Project Assets
Impairment charges				$ 0.8
Power Purchase Agreement
Project Assets
Sale leaseback transaction, net book value		$ 242	167.5
Trinity College Project
Project Assets
Power capacity under construction phase | kW		250
Impairment charges		$ 1.3
UConn Project
Project Assets
Power capacity under construction phase | MW		1
Impairment charges		$ 1.3
Toyota Project
Project Assets
Impairment charges		$ 3.6
Non-recoverable costs charged off as cost of revenue			22.9
Amount of charges for the difference between carrying value of the project asset less the carrying value of inventory components			$ 22.1
CT RFP-1, Hartford, CT | Hartford
Project Assets
Capacity Of Plant | MW	7.4
SCEF - Hartford, CT | Hartford
Project Assets
Capacity Of Plant | MW	1

Property, Plant and Equipment_2

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	$ 245,386	$ 197,669
Accumulated depreciation	(114,700)	(108,001)
Property, plant and equipment, net	130,686	89,668
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	524	524
Building and Building Improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	$ 26,581	21,430
Building and Building Improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	10 years
Building and Building Improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	26 years
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	$ 144,242	136,554
Machinery and Equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Machinery and Equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	8 years
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	$ 5,451	5,211
Estimated Useful Life	10 years
Construction in Progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	$ 68,588	$ 33,950

Property, Plant and Equipment -

Property, Plant and Equipment - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Property, Plant and Equipment.
Impairment charge	$ 0	$ 0	$ 1,000
Depreciation expense	$ 8,000	$ 5,100	$ 5,800

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Oct. 31, 2023
Goodwill And Intangible Assets
Goodwill	$ 4,075			$ 4,075
Intangible assets, net	14,779			16,076
Amortization expenses	1,300
Versa & Bridgeport Fuel Cell Project Acquisitions
Goodwill And Intangible Assets
Intangible assets, net	14,800			$ 16,100
Versa Acquisition
Goodwill And Intangible Assets
Goodwill		$ 4,100	$ 4,100
Bridgeport Fuel Cell, LLC
Goodwill And Intangible Assets
Amortization expenses	$ 1,300	$ 1,300	$ 1,300

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Summary of Intangible Assets (Details) - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Goodwill and Intangible Assets
Gross Amount	$ 21,912	$ 21,912
Accumulated Amortization	(7,133)	(5,836)
Net Amount	14,779	16,076
In Process Research And Development
Goodwill and Intangible Assets
Gross Amount	9,592	9,592
Net Amount	9,592	9,592
Bridgeport PPA
Goodwill and Intangible Assets
Gross Amount	12,320	12,320
Accumulated Amortization	(7,133)	(5,836)
Net Amount	$ 5,187	$ 6,484

Accrued Liabilities - Schedule

Accrued Liabilities - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Accrued Liabilities
Accrued payroll and employee benefits	$ 9,808	$ 7,752
Consideration payable to a customer	2,515	3,958
Accrued service agreement and PPA costs	10,574	10,742
Accrued legal, taxes, professional and other	5,230	3,861
Accrued severance costs	2,235
Accrued liabilities	$ 30,362	$ 26,313

Accrued Liabilities - Schedul_2

Accrued Liabilities - Schedule of Accrued Liabilities Detail (Details) - USD ($) $ in Millions	Oct. 31, 2024	Oct. 31, 2023
Accrued Liabilities
Loss accruals on service contracts	$ 9	$ 9.5
Accruals for performance guarantees	$ 1.5	$ 1.2

Leases - Additional Information

Leases - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Leases
Operating lease expense	$ 1,404	$ 1,486	$ 1,521
Operating lease, weighted average remaining lease term	16 years
Operating lease, weighted average discount rate	6.90%
Operating lease, payments	$ 1,266	$ 1,226	$ 1,438

Leases - Summary of Undiscounte

Leases - Summary of Undiscounted Maturities of Operating Lease and Finance Lease Liabilities (Details) $ in Thousands	Oct. 31, 2024 USD ($)
Operating Leases
Due Year 1	$ 1,361
Due Year 2	1,374
Due Year 3	1,407
Due Year 4	1,375
Due Year 5	795
Thereafter	11,923
Total undiscounted lease payments	18,235
Less imputed interest	(8,534)
Total discounted lease payments	$ 9,701

Debt - Schedule of Debt (Detail

Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Debt Instrument [Line Items]
Long-term Line of Credit	$ 70,067	$ 77,510
Finance lease obligations		$ 12
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Deferred finance costs	$ (4,215)	$ (3,526)
Total debt and finance obligations	131,662	119,467
Current portion of long-term debt and finance obligations	(15,924)	(10,067)
Long-term debt and finance obligations	115,738	109,400
Export-Import Bank of the United States Financing Facility
Debt Instrument [Line Items]
Long-term Line of Credit	10,104
Liberty Bank Term Loan Agreement (Derby Senior Back Leverage Loan Facility)
Debt Instrument [Line Items]
Long-term Line of Credit	5,825
Connecticut Green Bank Term Loan Agreement (Derby Senior Back Leverage Loan Facility)
Debt Instrument [Line Items]
Long-term Line of Credit	2,689
Connecticut Green Bank Loan (Groton Subordinated Back Leverage Loan Facility)
Debt Instrument [Line Items]
Long-term Line of Credit	8,000	8,000
Liberty Bank Term Loan Agreement (Groton Senior Back Leverage Loan Facility)
Debt Instrument [Line Items]
Long-term Line of Credit	5,437	5,876
Amalgamated Bank Loan (Groton Senior Back Leverage Loan Facility)
Debt Instrument [Line Items]
Long-term Line of Credit	5,420	5,873
Connecticut Green Bank Loan (Subordinated Back Leverage Loan Facility)
Debt Instrument [Line Items]
Long-term Line of Credit	3,500
Finance Obligation for Sale-Lease Back Transactions [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	18,811	18,814
State of Connecticut Loan
Debt Instrument [Line Items]
Long-term Line of Credit	$ 6,024	$ 6,908

Debt - Aggregate Annual Princip

Debt - Aggregate Annual Principal Payments under Loan Agreements and Finance Lease Obligations (Details) $ in Thousands	Oct. 31, 2024 USD ($)
Debt
Year 1	$ 14,440
Year 2	14,759
Year 3	10,930
Year 4	12,237
Year 5	11,305
Thereafter	61,659	[1]
Debt and Finance Leases, Future Minimum Payments Due	$ 125,330
[1] The annual principal payments included above only include sale-leaseback payments whereas the difference between debt outstanding as of October 31, 2024 and the annual principal payments represent accreted interest and amounts included in the finance obligation that exceed required principal payments.

Debt - EXIM Financing (Details)

Debt - EXIM Financing (Details) - EXIM $ in Millions		12 Months Ended
	Oct. 31, 2024 USD ($) MW	Oct. 31, 2024 USD ($) item MW
Debt Instrument [Line Items]
Number of fuel cells | item		42
Capacity Of Fuel Cell | MW	1.4	1.4
Proceeds from Long-Term Lines of Credit	$ 10.1	$ 9.2
Interest rate (as a percent)	5.81%	5.81%
Debt instrument term	7 years
Net proceeds from issuance debt	$ 9.2
Minimum cash balance	$ 100	$ 100

Debt - Derby Back Leverage Fina

Debt - Derby Back Leverage Financing (Details) $ in Thousands				12 Months Ended
	Aug. 25, 2024	Apr. 25, 2024 USD ($)	Aug. 18, 2023 USD ($) multiplier	Oct. 31, 2024 USD ($)	Oct. 31, 2023 USD ($)
Debt Instrument [Line Items]
Payments of debt issuance costs				$ 1,159	$ 3,469
Back Leverage Financing
Debt Instrument [Line Items]
Gross proceeds from debt		$ 13,000	$ 20,000
Payments of debt issuance costs		200	400
Net proceeds from debt		12,800	19,600
Payment to fund DSCR Reserve Accounts		900	1,700
Payment to fund O&M Reserve Accounts			6,500
Proceeds from debt, distributed to company		11,500	11,100
Legal fees		$ 200
Output shortfall payments			1,300
Unrestricted cash			$ 6,800
Trailing period for debt service coverage ratio		12 months	12 months
Term to acquire interest at flip point		90 days	90 days
Back Leverage Financing | Minimum
Debt Instrument [Line Items]
Basis points		1.1
Debt service coverage ratio			1.10%
Back Leverage Financing | Groton Senior Back Leverage Loan Facility
Debt Instrument [Line Items]
Debt Instrument, Amortization Period			10 years
Debt instrument term			7 years
Term of interest only period			84 months
Back Leverage Financing | Groton Senior Back Leverage Loan Facility | Prepayment on or prior to the second anniversary
Debt Instrument [Line Items]
Prepayment fee (as percentage)			3%
Back Leverage Financing | Groton Senior Back Leverage Loan Facility | Prepayment after second anniversary of the closing date but on or prior to the fourth anniversary
Debt Instrument [Line Items]
Prepayment fee (as percentage)			2%
Back Leverage Financing | Groton Senior Back Leverage Loan Facility | Prepayment after fourth anniversary of the closing date but on or prior to the seventh anniversary
Debt Instrument [Line Items]
Prepayment fee (as percentage)			1%
Back Leverage Financing | Groton Senior Back Leverage Loan Facility | Minimum
Debt Instrument [Line Items]
Debt service coverage ratio			1.20%
Back Leverage Financing | Derby Senior Back Leverage Loan Facility
Debt Instrument [Line Items]
Interest rate (as a percent)		7.25%
Debt instrument term		7 years
Back Leverage Financing | Derby Senior Back Leverage Loan Facility | Prepayment on or prior to the second anniversary
Debt Instrument [Line Items]
Prepayment fee (as percentage)	2%
Back Leverage Financing | Derby Senior Back Leverage Loan Facility | Prepayment after second anniversary of the closing date but on or prior to the fourth anniversary
Debt Instrument [Line Items]
Prepayment fee (as percentage)	3%
Back Leverage Financing | Derby Senior Back Leverage Loan Facility | Prepayment after fourth anniversary of the closing date but on or prior to the seventh anniversary
Debt Instrument [Line Items]
Prepayment fee (as percentage)	1%
Back Leverage Financing | Derby Senior Back Leverage Loan Facility | Minimum
Debt Instrument [Line Items]
Basis points		1.25
Back Leverage Financing | Groton Subordinated Back Leverage Loan Facility
Debt Instrument [Line Items]
Basis points			2.75
Excess cashflow available to borrower (as a percent)			50%
Term following commercial operations date and termination of the Amended and Restated PPA			20 years
Back Leverage Financing | Groton Subordinated Back Leverage Loan Facility | Step Down Date
Debt Instrument [Line Items]
Interest rate (as a percent)			8%
Back Leverage Financing | Groton Subordinated Back Leverage Loan Facility | After the Step Down Date
Debt Instrument [Line Items]
Floor rate (as a percent)			5%
Back Leverage Financing | Groton Subordinated Back Leverage Loan Facility | Maximum | After the Step Down Date
Debt Instrument [Line Items]
Interest rate (as a percent)			8%
Back Leverage Financing | Liberty Lender
Debt Instrument [Line Items]
Payment to fund DSCR Reserve Accounts			$ 830
Payment to fund O&M Reserve Accounts		$ 600	$ 3,250
Interest rate (as a percent)			6.75%
Back Leverage Financing | Liberty Lender | Term Loan Facility
Debt Instrument [Line Items]
Loan provided by lender (as a percentage)		68%	50%
Back Leverage Financing | Amalgamated Lender
Debt Instrument [Line Items]
Payment to fund DSCR Reserve Accounts			$ 830
Payment to fund O&M Reserve Accounts			$ 3,250
Annual carbon emissions price multiplier | multiplier			12.66
Back Leverage Financing | Amalgamated Lender | Carbon Offset Event Continuing
Debt Instrument [Line Items]
Interest rate (as a percent)			7.32%
Back Leverage Financing | Amalgamated Lender | Carbon Offset Event Non Continuing
Debt Instrument [Line Items]
Interest rate (as a percent)			6.07%
Back Leverage Financing | Amalgamated Lender | Term Loan Facility
Debt Instrument [Line Items]
Loan provided by lender (as a percentage)			50%
Back Leverage Financing | Groton Senior Back Leverage Loans
Debt Instrument [Line Items]
Payment to fund DSCR Reserve Accounts			$ 300
Back Leverage Financing | Groton Senior Back Leverage Loans | Term Loan Facility
Debt Instrument [Line Items]
Term loan facility			12,000
Back Leverage Financing | Derby Senior Back Leverage Lenders
Debt Instrument [Line Items]
Payment to fund DSCR Reserve Accounts		$ 400
Back Leverage Financing | Derby Senior Back Leverage Lenders | Term Loan Facility
Debt Instrument [Line Items]
Term loan facility		9,500
Back Leverage Financing | Groton Subordinated Back Leverage Lenders | Term Loan Facility
Debt Instrument [Line Items]
Term loan facility			$ 8,000
Back Leverage Financing | Derby Subordinated Back Leverage Lenders | Term Loan Facility
Debt Instrument [Line Items]
Term loan facility		3,500
Connecticut Green Bank Term Loan Agreement (Derby Senior Back Leverage Loan Facility)
Debt Instrument [Line Items]
Payment to fund O&M Reserve Accounts		$ 300
Connecticut Green Bank Loan (Derby Subordinated Back Leverage Loan Facility)
Debt Instrument [Line Items]
Loan provided by lender (as a percentage)		32%
Interest rate (as a percent)		8%

Debt - OpCo Financing Facility

Debt - OpCo Financing Facility (Details)		12 Months Ended
	May 19, 2023 USD ($) project	Oct. 31, 2024 USD ($)	Oct. 31, 2023 USD ($)
Debt Instrument [Line Items]
Derivative asset		$ 1,200,000	$ 4,100,000
Number of leased projects ownership reacquired | project	3
Proceeds from the issuance of debt		23,104,000	100,500,000
Bridgeport Fuel Cell Project
Debt Instrument [Line Items]
Encumbrance amount	$ 11,400,000
Bridgeport Fuel Cell Project | Liberty Bank, Fifth Third Bank and Connecticut Green Bank
Debt Instrument [Line Items]
Repayments of debt	11,400,000
Pfizer Project
Debt Instrument [Line Items]
Future payments included in financing obligation for the remaining lease	15,700,000
Riverside Regional Water Quality Control Plant Project
Debt Instrument [Line Items]
Future payments included in financing obligation for the remaining lease	3,700,000
Santa Rita Jail Project
Debt Instrument [Line Items]
Future payments included in financing obligation for the remaining lease	$ 2,800,000
OpCo Financing Facility
Debt Instrument [Line Items]
Number of projects serving as security | project	6
Payments of debt issuance costs	$ 2,900,000
Funds released from restricted and unrestricted reserve account	7,300,000
Capital expenditure reserve funded out of debt	14,500,000
Funds Released from Restricted Cash	11,200,000
Proceeds from debt, distributed to company	34,900,000
Unrestricted cash	46,100,000
Capital Expenditure Reserve	$ 29,000,000
Debt Instrument, Period After Closing To Enter Hedge Transaction	30 days
Gain from fair value adjustment of debt		$ 3,100,000	$ 3,300,000
Threshold annual operating expense budget as percent of base case model, approval from lenders	115%
Annual operating expense budget approval from lenders, lending percent	50%
Trailing period for debt service coverage ratio	12 months
Debt service coverage ratio, testing frequency	6 months
Quarterly principal payment	$ 675,000
Proceeds from the issuance of debt	77,600,000
OpCo Financing Facility | Sale-leaseback Arrangements with PNC
Debt Instrument [Line Items]
Repayments of debt	$ 15,000,000
OpCo Financing Facility | Interest Rate Swap | First four years
Debt Instrument [Line Items]
Net interest rate	6.366%
OpCo Financing Facility | Interest Rate Swap | Thereafter
Debt Instrument [Line Items]
Net interest rate	6.866%
OpCo Financing Facility | LIPA Yaphank Solid Waste Management Project
Debt Instrument [Line Items]
Extension term of gas agreement	3 years
Period to exercise option to purchase member interest in tax equity partnership	6 months
OpCo Financing Facility | Maximum
Debt Instrument [Line Items]
Notional amount of hedge	105%
OpCo Financing Facility | Minimum
Debt Instrument [Line Items]
Notional amount of hedge	75%
Debt service coverage ratio	1.20%
OpCo Financing Facility | Letter of credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 6,500,000
Term to maintain debt service coverage ratio	6 months
OpCo Financing Facility | Senior Term Loan
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 80,500,000
Principal amortization period	17 years
Debt instrument term	7 years
Debt service coverage ratio	1.30%
Debt instrument, face amount	$ 80,500,000
OpCo Financing Facility | Senior Term Loan | Applicable interest period one
Debt Instrument [Line Items]
Interest period	1 month
OpCo Financing Facility | Senior Term Loan | Applicable interest period two
Debt Instrument [Line Items]
Interest period	3 months
OpCo Financing Facility | Senior Term Loan | Applicable interest period three
Debt Instrument [Line Items]
Interest period	6 months
OpCo Financing Facility | Senior Term Loan | SOFR rate
Debt Instrument [Line Items]
Initial interest period	3 months
OpCo Financing Facility | Senior Term Loan | SOFR rate | First four years
Debt Instrument [Line Items]
Interest rate, basis points	2.50%
OpCo Financing Facility | Senior Term Loan | SOFR rate | Thereafter
Debt Instrument [Line Items]
Interest rate, basis points	3%
OpCo Financing Facility | Senior Term Loan | Base rate | First four years
Debt Instrument [Line Items]
Interest rate, basis points	1.50%
OpCo Financing Facility | Senior Term Loan | Base rate | Thereafter
Debt Instrument [Line Items]
Interest rate, basis points	2%
OpCo Financing Facility | Senior Term Loan | Interest Rate Swap
Debt Instrument [Line Items]
Notional amount of hedge	100%
Interest rate	3.716%
Connecticut Green Bank Notes
Debt Instrument [Line Items]
Repayments of debt	$ 1,800,000
PNC Energy Capital, LLC
Debt Instrument [Line Items]
Repayments of debt	$ 7,300,000

Debt - Other Instruments (Detai

Debt - Other Instruments (Details)		1 Months Ended			12 Months Ended
	Aug. 18, 2023 USD ($)	Apr. 30, 2023 USD ($) position	Jan. 31, 2019 USD ($) position	Nov. 30, 2015 USD ($) position	Oct. 31, 2024 USD ($)	Oct. 31, 2023 USD ($)	Oct. 31, 2022 USD ($)
Debt Instrument [Line Items]
Repayments of long term debt					$ 11,699,000	$ 47,830,000	$ 9,544,000
Long-term line of credit					70,067,000	77,510,000
Liberty Bank Term Loan Agreement (Bridgeport Fuel Cell Project)
Debt Instrument [Line Items]
Long-term line of credit					5,825,000
Connecticut Green Bank Loan (Subordinated Back Leverage Loan Facility)
Debt Instrument [Line Items]
Long-term line of credit					3,500,000
Back Leverage Financing | Liberty Lender
Debt Instrument [Line Items]
Interest rate (as a percent)	6.75%
Connecticut Green Bank Loans
Debt Instrument [Line Items]
Repayments of Debt	$ 3,000,000
Finance Obligation for Sale-Lease Back Transactions
Debt Instrument [Line Items]
Long-term line of credit					18,811,000	18,814,000
Finance obligations for sale leaseback agreements
Debt Instrument [Line Items]
Future payments included in financing obligation for the remaining lease					$ 10,500,000
Purchase right percentage of projected assets at fair market value					31%
Finance obligations for sale leaseback agreements | PNC Energy Capital, LLC
Debt Instrument [Line Items]
Long-term line of credit					$ 18,800,000
State of Connecticut Loan
Debt Instrument [Line Items]
Long-term line of credit					$ 6,024,000	$ 6,908,000
Debt instrument, face amount				$ 10,000,000
Interest rate (as a percent)				2%
Debt instrument term				15 years
Debt instrument, payment terms, period principal payments are deferred				4 years
Debt instrument, date of first required payment				Dec. 01, 2019
Amount of loan forgiveness			$ 2,000,000
Loans Forgiveness Terms					if the Company created 165 full-time positions and retained 538 full-time positions for two consecutive years (as amended from time to time, the “Employment Obligation”) as measured on October 28, 2017 (as amended from time to time, the “Target Date”). The Assistance Agreement was subsequently amended in April 2017 to extend the Target Date by two years to October 28, 2019.
Number of full time positions required to be created | position			91	165
Number of full time positions required to be retained | position		538	538	538
Consecutive term for average number of employees		24 months	24 months	2 years	24 months
Principal payable number of employee under employee obligation target		$ 14,225			$ 14,225
Number of minimum full time positions required to be maintained | position		91
Number of minimum full time positions required to be maintained including additional employment positions | position		629
Additional credits to be earned		$ 2,000,000
Number of days within job audit					90 days
Average number of full time positions					389
Amount of loan reclassified to current					$ 2,100,000
Number of days following employment period		90 days
Amount of fee and interest payable					$ 0
State of Connecticut Loan | Maximum
Debt Instrument [Line Items]
Amount of loan forgiveness				$ 5,000,000

Stockholders' Equity and Warr_2

Stockholders' Equity and Warrant Liabilities (Details) - USD ($) $ / shares in Units, $ in Millions				12 Months Ended
	Oct. 31, 2024	Apr. 10, 2024	Jul. 12, 2022	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022	Oct. 11, 2023	Oct. 10, 2023
Stockholders' Equity and Warrant Liabilities
Number of incremental common stock shares approved								500,000,000
Common stock, shares authorized (in shares)	1,000,000,000			1,000,000,000	1,000,000,000		1,000,000,000	500,000,000
Common Stock
Stockholders' Equity and Warrant Liabilities
Shares sold during the period				5,302,378	1,477,361	1,279,897
Amended Open Market Sales Agreement | Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canacord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC
Stockholders' Equity and Warrant Liabilities
Shares sold during the period				5,300,000
Percentage of sales commission			2%
Gross proceeds from issuance of common stock to date under the amended sales agreement	$ 95.1			$ 95.1
Amended Open Market Sales Agreement | Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canacord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC | Common Stock
Stockholders' Equity and Warrant Liabilities
Shares sold during the period	5,300,000
Percentage of sales commission		2%
Aggregate offering price		$ 300
Average sale price per share for sales to date under the amended sales agreement	$ 17.93			$ 17.93	$ 67.49
Gross proceeds from issuance of common stock to date under the amended sales agreement	$ 95.1			$ 95.1	$ 99.7
Common stock issuance, net of fees	92.6				97.4
Sales commission	1.9
Payments of underwriting discounts and commissions	0.6				$ 2.3
Number of shares sold to date					1,500,000
Offering price	$ 204.9			$ 204.9
Amended Open Market Sales Agreement | Maximum | Jefferies LLC, B. Riley Securities, Inc., Barclays Capital Inc., BMO Capital Markets Corp., BofA Securities, Inc., Canacord Genuity LLC, Citigroup Global Markets Inc., J.P. Morgan Securities LLC and Loop Capital Markets LLC | Common Stock
Stockholders' Equity and Warrant Liabilities
Shares sold during the period			3,200,000

Redeemable Preferred Stock (Det

Redeemable Preferred Stock (Details) - $ / shares	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Redeemable Preferred Stock
Preferred stock, par value	$ 0.01
Maximum
Redeemable Preferred Stock
Preferred stock, shares authorized	250,000
Series B Preferred Stock
Redeemable Preferred Stock
Preferred stock, shares authorized	105,875
Preferred stock, dividend rate, percentage	5%	5%	5%

Redeemable Preferred Stock - Re

Redeemable Preferred Stock - Redeemable Series B Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Redeemable Preferred Stock
Temporary equity, carrying amount, attributable to parent	$ 59,857	$ 59,857
Series B Preferred Stock
Redeemable Preferred Stock
Preferred stock, shares authorized	105,875
Preferred stock, liquidation preference per share	$ 1,000
Preferred stock, shares issued	64,020	64,020
Preferred stock shares outstanding	64,020	64,020
Temporary equity, carrying amount, attributable to parent	$ 59,900	$ 59,900

Redeemable Preferred Stock - Di

Redeemable Preferred Stock - Dividends, Liquidations and Conversion Rights (Details) - Series B Preferred Stock - USD ($)	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023
Redeemable Preferred Stock
Preferred stock, dividends per share, declared	$ 50
Dividends, preferred stock, cash	$ 3,200,000	$ 3,200,000
Cumulative unpaid dividends	$ 800,000	800,000
Preferred stock, liquidation preference per share	$ 1,000
Payment on junior shares	$ 0
Preferred stock, liquidation preference value	$ 64,020,000	$ 64,020,000
Shares of common stock issued upon conversion	0.0197
Stock conversion price	$ 50,760
Percent of conversion price to exceed to exercise conversion right	150%
Number of trading days	20 days
Number of consecutive trading days	30 days

Redeemable Preferred Stock - _2

Redeemable Preferred Stock - Redemption and Voting Rights (Details) - Series B Preferred Stock	12 Months Ended
	Oct. 31, 2024
Redeemable Preferred Stock
Percentage of voting rights	50%
Consecutive number of years	2 years
Percentage of aggregate voting power	100%
Number of trading days	20 days
Number of consecutive trading days	30 days
Percentage of conversion price	105%
Discount on market price of shares of common stock	5%
Preferred stock, voting rights	no voting rights
Minimum
Redeemable Preferred Stock
Percentage of consideration excluding cash payments for fractional shares	90%
Common Stock
Redeemable Preferred Stock
Number of trading days	5 days
Number of consecutive trading days	10 days

Segment Information - Additiona

Segment Information - Additional Information (Details)	12 Months Ended
	Oct. 31, 2024 item
Segment Information
Number of identified business segment	1

Segment Information - Revenues

Segment Information - Revenues by Geographic Locations (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 112,132	$ 123,394	$ 130,484
United States
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	86,962	63,289	60,290
South Korea
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	22,836	58,432	68,341
Europe
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,919	$ 1,673	$ 1,853
CANADA
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 415

Benefit Plans - Additional Info

Benefit Plans - Additional Information (Details)							3 Months Ended	12 Months Ended
	Nov. 17, 2024	Apr. 04, 2024 shares	Dec. 11, 2023 USD ($) item shares	May 22, 2023 shares	Dec. 05, 2022 USD ($) item	Dec. 10, 2021 item USD ($)	Jan. 31, 2024 shares	Oct. 31, 2024 USD ($) shares	Oct. 31, 2023 USD ($) shares	Oct. 31, 2022 USD ($) shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted		0
Noninterest Expense Directors Fees | $								$ 200,000	$ 200,000	$ 200,000
Employer Matching Contribution Percentage								2%
Defined Contribution Plan, Cost Recognized | $								$ 1,300,000	$ 1,100,000	$ 500,000
unrestricted common stock								6,651	3,454	2,562
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock or Unit Expense | $								$ 14,300,000
Restricted Stock or Unit Expense weighted average period								2 years
Restricted Stock Units | Senior Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Awards and Units, Granted, Shares			218,292
Performance Shares | Senior Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Awards and Units, Granted, Shares			109,146
Time Based Awards | Senior Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Awards and Units, Granted, Shares			109,146
Time Based Awards | Salaried Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Awards and Units, Granted, Shares								204,737
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock awards, general vesting period								4 years
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock awards, general vesting period								3 years
2018 Omnibus Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized		1,444,444
Common stock, shares available for issuance								754,518
2018 Omnibus Incentive Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares to be issued on exercise of stock options		61,111
Additional number of shares authorized		833,333
Number of shares authorized		1,444,444
2018 Omnibus Incentive Plan | Maximum | Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares reserved for issuance								146,397
Amended and Restated 2018 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share price as percentage of offering price				85%
ESOP, period for which sale of shares is restricted				6 months
Amended and Restated 2018 Employee Stock Purchase Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares that can be purchased by individual participant				33
Additional number of shares authorized				16,666
Number of shares authorized				18,055
Long Term Incentive Plan Fiscal 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of award components | item						2
Common stock, shares reserved for issuance								5,849
Long Term Incentive Plan Fiscal 2022 | Relative Total Shareholder Return Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award Calibration Percentage						100%
Variance from Award Calibration Percentage						50%
Award Cap, Percent						200%
Award Additional Cap, Percent						100%
Threshold Consecutive Trading Days | $						20
Long Term Incentive Plan Fiscal 2022 | Relative Total Shareholder Return Performance Shares | Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percent of Performance Payout	52.665%
Long Term Incentive Plan Fiscal 2022 | Time Based Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage										33%
Long Term Incentive Plan Fiscal 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of award components | item					2
Common stock, shares reserved for issuance								35,539
Long Term Incentive Plan Fiscal 2023 | Relative Total Shareholder Return Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award Calibration Percentage					100%
Variance from Award Calibration Percentage					50%
Award Cap, Percent					200%
Award Additional Cap, Percent					100%
Threshold Consecutive Trading Days | $					60
Capital Shares reserved for future issuance					200%
Long Term Incentive Plan Fiscal 2023 | Time Based Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage									33%
Long Term Incentive Plan Fiscal 2023 | Performance and Time Based Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock or Unit Expense weighted average period		3 years
Long Term Incentive Plan Fiscal 2024
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of award components | item			2
Common stock, shares reserved for issuance								105,009
Long Term Incentive Plan Fiscal 2024 | Relative Total Shareholder Return Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award Calibration Percentage			100%
Variance from Award Calibration Percentage			0.50%
Award Cap, Percent			200%
Award Additional Cap, Percent			100%
Threshold Consecutive Trading Days | $			20
Capital Shares reserved for future issuance			200%
Long Term Incentive Plan Fiscal 2024 | Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of Target Performance								100%
Long Term Incentive Plan Fiscal 2024 | Time Based Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage								33%
Long Term Incentive Plan Fiscal 2024 | Time Based Awards | Senior Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Phantom Stock Awards and Units, Granted, Shares							109,146
Long Term Incentive Plan Fiscal 2024 | Time Based Awards | Salaried Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage								33%

Benefit Plans - Schedule of Sha

Benefit Plans - Schedule of Share-Based Compensation Reflected in Consolidated Statement of Operations and Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	$ 11,471	$ 11,588	$ 6,580
Costs of Revenues
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	1,460	1,502	706
Administrative and selling expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	8,583	8,657	5,418
Research and Development Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	$ 1,428	$ 1,429	$ 456

Benefit Plans - Summary of RSU

Benefit Plans - Summary of RSU and PSU activity (Details)	12 Months Ended
	Oct. 31, 2024 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Awards and Units, Outstanding, Shares, Beginning Balance | shares	217,947
Restricted Stock Awards and Units, Vested, Shares | shares	(76,420)
Restricted Stock Awards and Units, Forfeited, Shares | shares	(47,995)
Restricted Stock Awards and Units, Outstanding, Shares, Ending Balance | shares	516,561
Restricted Stock Awards and Units, Outstanding, Weighted-Average Fair Value, Beginning Balance | $ / shares	$ 151.89
Restricted Stock Awards and Units, Vested, Weighted-Average Fair Value | $ / shares	210.12
Restricted Stock Awards and Units, Forfeited, Weighted-Average Fair Value | $ / shares	67.96
Restricted Stock Awards and Units, Outstanding, Weighted-Average Fair Value, Ending Balance | $ / shares	$ 64.53
Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Awards and Units, Granted, Shares | shares	109,146
Restricted Stock Awards and Units, Granted, Weighted-Average Fair Value | $ / shares	$ 48.9
Time Based Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Awards and Units, Granted, Shares | shares	313,883
Restricted Stock Awards and Units, Granted, Weighted-Average Fair Value | $ / shares	$ 38.13

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Loss Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Income Taxes
U.S.	$ (140,713)	$ (95,910)	$ (145,439)
Foreign	(16,040)	(11,565)	(974)
Loss before provision for income taxes	$ (156,753)	$ (107,475)	$ (146,413)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Operating Loss Carryforwards [Line Items]
Income tax expense (benefit)	$ 25	$ 581	$ 819
Franchise tax expense	500	900	$ 1,000
Unrecognized Tax Benefits	0	0
Unrecognized tax benefits, provision for interest or penalties	0	$ 0
Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	1,060,000
Net operating loss carryforwards subject to expiration	549,000
Net operating loss carryforwards not subject to expiration	506,000
NOL carryforward for financial statement purposes	588,000
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards subject to expiration	585,100
Available tax credits	$ 13,700

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Federal Statutory Income Tax Rate To Effective Income Tax Rate (Details)	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Income Taxes
Statutory federal income tax rate	(21.00%)	(21.00%)	(21.00%)
State taxes, net of Federal benefits	(4.40%)	(3.20%)	(3.60%)
Foreign withholding tax	0.10%	0.50%	0.60%
Net operating loss expiration, impairment and true-ups	(1.10%)	6.10%	8.70%
Nondeductible expenditures	0.20%	2.10%	1.40%
Change in tax rates	(0.40%)	2.80%	0.30%
Other, net	0.30%	0.60%	0.70%
Deferred only adjustment	(0.40%)	(0.10%)	(0.10%)
Valuation allowance	26.80%	12.70%	13.60%
Effective income tax rate	0.10%	0.50%	0.60%

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023
Income Taxes
Deferred tax assets, Compensation and benefit accruals	$ 7,344	$ 6,026
Deferred tax assets, Bad debt and other allowances	2,695	1,945
Deferred tax assets, Capital loss and tax credit carry-forwards	16,296	14,701
Deferred tax assets, Net operating losses (domestic and foreign)	170,780	139,900
Deferred tax assets, Deferred license revenue	871	1,148
Deferred tax assets, Accumulated depreciation	15,969	14,051
Deferred tax assets, Grant revenue	210	323
Deferred tax assets, Excess business interest	5,860	6,406
Deferred tax assets, Operating lease liabilities	1,840	1,879
Deferred tax assets, Capitalized research and development	18,305	9,729
Deferred tax assets, Mark to market	1,702	987
Deferred tax assets, Other	150	4
Gross deferred tax assets:	242,022	197,099
Deferred tax assets, Valuation allowance	(228,139)	(193,477)
Deferred tax assets after valuation allowance	13,883	3,622
Net loss attributable to noncontrilling interests	(7,567)
Deferred tax liability, In process research and development	(2,322)	(2,293)
Deferred tax liability Right of use assets	(1,556)	(1,600)
Deferred tax liability Other	(2,745)	(9)
Net deferred tax liability	$ (307)	$ (280)

Loss Per Share - Schedule of Ca

Loss Per Share - Schedule of Calculation of Basic and Diluted Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Numerator
Net loss attributable to FuelCell Energy, Inc.	$ (126,009)	$ (107,568)	$ (142,722)
Series B preferred stock dividends	(3,200)	(3,200)	(3,200)
Net loss attributable to common stockholders	$ (129,209)	$ (110,768)	$ (145,922)
Denominator
Weighted average common shares outstanding - basic	16,505,257	13,991,593	12,771,305
Weighted average common shares outstanding - diluted	16,505,257	13,991,593	12,771,305
Net loss to common stockholders per share - basic	$ (7.83)	$ (7.92)	$ (11.43)
Net loss to common stockholders per share - diluted	$ (7.83)	$ (7.92)	$ (11.43)
Series B Preferred Stock
Numerator
Series B preferred stock dividends	$ (3,200)	$ (3,200)	$ (3,200)

Loss Per Share - Schedule of Po

Loss Per Share - Schedule of Potentially Dilutive Securities Excluded from the Diluted Loss Per Share Calculation (Details) - shares	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from diluted loss per share calculation	518,396	219,976	85,965
Series B Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Preferred stock, dividend rate, percentage	5%	5%	5%
Employee Stock Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from diluted loss per share calculation	574	610	674
Unvested Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from diluted loss per share calculation	516,561	218,105	84,029
5% Series B Cumulative Convertible Perpetual Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from diluted loss per share calculation	1,261	1,261	1,261

Restricted Cash - Additional In

Restricted Cash - Additional Information (Details) - USD ($) $ in Millions	Oct. 31, 2024	Oct. 31, 2023
Restricted Cash.
Restricted cash and cash equivalents	$ 60.8	$ 49.6

Restricted Cash - Summary of Al

Restricted Cash - Summary of Allocation of Restricted Cash (Details) - USD ($) $ in Thousands	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Restricted Cash.
Cash Restricted for Outstanding Letters of Credit	$ 14,152	$ 14,152
Cash Restricted for Crestmark Sale-Leaseback Transactions	2,908	2,901
Debt Service and Performance Reserves related to OpCo Financing Facility	24,721	19,698
Debt Service and Performance Reserves related to the Senior and Subordinated Back Leverage Loan Facilities	12,869	9,294
Other	6,100	3,579
Total Restricted Cash	60,750	49,624
Restricted Cash and Cash Equivalents - Short-Term	(12,161)	(5,159)	$ (4,423)
Restricted Cash and Cash Equivalents - Long-Term	$ 48,589	$ 44,465	$ 18,566

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) $ in Millions	3 Months Ended	12 Months Ended
	Oct. 31, 2023 USD ($) MW	Oct. 31, 2024 USD ($) MW	Oct. 31, 2023 USD ($)
Commitments And Contingencies [Line Items]
Derivative net gain (loss)		$ (6.9)	$ 4.1
Derivative liabilities	$ 0	$ 4	$ 0
Derivative Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Recorded unconditional purchase obligation		$ 90.8
Derivative asset	$ 4.1	$ 1.2	$ 4.1
CT-RFP 2 Derby 14.9 Mega Watt Project
Commitments And Contingencies [Line Items]
Capacity of plant | MW		14.9
Tulare Biomat Project
Commitments And Contingencies [Line Items]
Term for procuring fuel		20 years
LIPA project
Commitments And Contingencies [Line Items]
Term for procuring fuel		7 years
LIPA project | Maximum
Commitments And Contingencies [Line Items]
Term for procuring fuel		20 years
Derby Project
Commitments And Contingencies [Line Items]
Term for procuring fuel		6 years
Derby Project | Maximum
Commitments And Contingencies [Line Items]
Term for procuring fuel		20 years
Derby Project 14.0 Mega Watt
Commitments And Contingencies [Line Items]
Capacity of plant | MW	14	14
Derby Project 2.8 Mega Watt
Commitments And Contingencies [Line Items]
Capacity of plant | MW	2.8	2.8
Toyota Project
Commitments And Contingencies [Line Items]
Term for procuring fuel		2 years
Toyota Project | Maximum
Commitments And Contingencies [Line Items]
Term for procuring fuel		20 years

Supplemental Cash Flow Inform_3

Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2022
Supplemental Cash Flow Information
Cash interest paid	$ 6,796	$ 3,088	$ 1,556
Income taxes paid	16	6	2
Noncash financing and investing activity:
Noncash reclassifications between inventory and project assets	4,586	1,987	1,260
Noncash reclassifications from inventory to fixed assets			1,552
Noncash reclassifications from other assets to project assets			2,375
Director stock compensation	159	225	305
Accrued noncontrolling interest distribution		148
Addition of operating lease liabilities	395	1,952
Addition of operating lease right-of-use assets	395	1,952
Noncash reduction in basis of project assets		6,330
Accrued purchases of fixed assets, cash to be paid in subsequent period	2,958	1,646	4,396
Accrued purchases of project assets, cash to be paid in subsequent period	$ 269	$ 4,515	$ 6,444

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event $ in Millions	Dec. 12, 2024 USD ($)	Nov. 15, 2024 USD ($) item
Subsequent Events
Percentage of workforce reduced		13%
Number of employees reduced | item		75
Groton Project
Subsequent Events
Tax equity financing transaction, commitment amount received	$ 4
Minimum
Subsequent Events
Aggregate restructuring-related costs and charges incurred		$ 1.7
Maximum
Subsequent Events
Aggregate restructuring-related costs and charges incurred		$ 2