Stem (STEM) 10-Q 2 May 24 2024 Q1 Quarterly report Financial data

Cover

Cover - shares	3 Months Ended
	Mar. 31, 2024	Apr. 25, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
Entity Registrant Name	STEM, INC.
Entity Incorporation, State or Country Code	DE
Entity File Number	001-39455
Entity Tax Identification Number	85-1972187
Entity Address, Address Line One	100 California St., 14th Fl.
Entity Address, City or Town	San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94111
Country Region	1
City Area Code	877
Local Phone Number	374-7836
Title of 12(b) Security	Common Stock, par value $0.0001
Trading Symbol	STEM
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		161,651,144
Entity Central Index Key	0001758766
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 112,804	$ 105,375
Short-term investments	0	8,219
Accounts receivable, net of allowances of $4,464 and $4,904 as of March 31, 2024 and December 31, 2023, respectively	239,934	302,848
Inventory, net	24,444	26,665
Deferred costs with suppliers	20,125	20,555
Other current assets (includes $41 and $73 due from related parties as of March 31, 2024 and December 31, 2023, respectively)	8,221	9,303
Total current assets	405,528	472,965
Energy storage systems, net	71,234	74,418
Contract origination costs, net	10,515	11,119
Goodwill	547,169	547,205
Intangible assets, net	155,008	157,146
Operating lease right-of-use assets	11,475	12,255
Other noncurrent assets	83,966	81,869
Total assets	1,284,895	1,356,977
Current liabilities:
Accounts payable	61,746	78,277
Accrued liabilities	78,487	76,873
Accrued payroll	11,188	14,372
Financing obligation, current portion	15,390	14,835
Deferred revenue, current portion	56,952	53,997
Other current liabilities (includes $203 and $31 due to related parties as of March 31, 2024 and December 31, 2023, respectively)	12,855	12,726
Total current liabilities	236,618	251,080
Deferred revenue, noncurrent	88,410	88,650
Asset retirement obligation	4,073	4,052
Convertible notes, noncurrent	524,200	523,633
Financing obligation, noncurrent	49,222	52,010
Lease liabilities, noncurrent	9,885	10,455
Other liabilities	436	416
Total liabilities	912,844	930,296
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.0001 par value; 1,000,000 shares authorized as of March 31, 2024 and December 31, 2023; zero shares issued and outstanding as of March 31, 2024 and December 31, 2023	0	0
Common stock, $0.0001 par value; 500,000,000 shares authorized as of March 31, 2024 and December 31, 2023; 161,526,782 and 155,932,880 issued and outstanding as of March 31, 2024 and December 31, 2023, respectively	16	16
Additional paid-in capital	1,216,197	1,198,716
Accumulated other comprehensive income (loss)	154	(42)
Accumulated deficit	(844,801)	(772,494)
Total Stem’s stockholders’ equity	371,566	426,196
Non-controlling interests	485	485
Total stockholders’ equity	372,051	426,681
Total liabilities and stockholders’ equity	$ 1,284,895	$ 1,356,977

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Accounts receivable, allowances	$ 4,464	$ 4,904
Other current assets	8,221	9,303
Other current liabilities	$ 12,855	$ 12,726
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	161,526,782	155,932,880
Common stock, shares outstanding (in shares)	161,526,782	155,932,880
Related Party
Other current assets	$ 41	$ 73
Other current liabilities	$ 203	$ 31

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue
Revenue	$ 25,469	$ 67,405
Cost of Revenue
Cost of Revenue	49,660	66,411
Gross (loss) profit	(24,191)	994
Operating expenses:
Sales and marketing	11,126	12,406
Research and development	14,136	13,444
General and administrative	18,560	17,797
Total operating expenses	43,822	43,647
Loss from operations	(68,013)	(42,653)
Other expense, net:
Interest expense, net	(4,707)	(1,777)
Other income (expense), net	566	(439)
Total other expense, net	(4,141)	(2,216)
Loss before (provision for) benefit from income taxes	(72,154)	(44,869)
(Provision for) benefit from income taxes	(153)	91
Net loss	$ (72,307)	$ (44,778)
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.46)	$ (0.29)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.46)	$ (0.29)
Weighted-average shares used in computing net loss per share to common stockholders, basic (in shares)	158,180,137	154,966,163
Weighted-average shares used in computing net loss per share to common stockholders, diluted (in shares)	158,180,137	154,966,163
Services and other revenue
Revenue
Revenue	$ 14,840	$ 14,673
Cost of Revenue
Cost of Revenue	9,984	11,504
Hardware revenue
Revenue
Revenue	10,629	52,732
Cost of Revenue
Cost of Revenue	$ 39,676	$ 54,907

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net loss	$ (72,307)	$ (44,778)
Other comprehensive loss:
Unrealized gain on available-for-sale securities	3	1,543
Foreign currency translation adjustment	193	127
Total other comprehensive loss	$ (72,111)	$ (43,108)

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Non-controlling Interests
Beginning balance (in shares) at Dec. 31, 2022		154,540,197
Beginning balance at Dec. 31, 2022	$ 552,167	$ 15	$ 1,185,364	$ (1,672)	$ (632,081)	$ 541
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises, net of statutory tax withholdings (in shares)		65,045
Stock option exercises, net of statutory tax withholdings	149		149
Issuance of common stock upon release of restricted stock units (in shares)		903,061
Issuance of common stock upon release of restricted stock units	1	$ 1
Stock-based compensation	8,108		8,108
Unrealized gain on available-for-sale securities	1,543			1,543
Foreign currency translation adjustment	127			127
Redemption of non-controlling interests	(72)					(72)
Net loss	(44,778)				(44,778)
Ending balance (in shares) at Mar. 31, 2023		155,508,303
Ending balance at Mar. 31, 2023	517,245	$ 16	1,193,621	(2)	(676,859)	469
Beginning balance (in shares) at Dec. 31, 2023		155,932,880
Beginning balance at Dec. 31, 2023	426,681	$ 16	1,198,716	(42)	(772,494)	485
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon release of restricted stock units (in shares)		5,593,902
Issuance of common stock upon release of restricted stock units	8,114		8,114
Stock-based compensation	9,367		9,367
Unrealized gain on available-for-sale securities	3			3
Foreign currency translation adjustment	193			193
Net loss	(72,307)				(72,307)
Ending balance (in shares) at Mar. 31, 2024		161,526,782
Ending balance at Mar. 31, 2024	$ 372,051	$ 16	$ 1,216,197	$ 154	$ (844,801)	$ 485

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
OPERATING ACTIVITIES
Net loss	$ (72,307)	$ (44,778)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	10,809	11,107
Non-cash interest expense, including interest expenses associated with debt issuance costs	422	386
Stock-based compensation	8,374	7,202
Non-cash lease expense	777	661
Accretion of asset retirement obligations	59	61
Impairment loss of energy storage systems	0	851
Impairment loss of project assets	345	0
Net (accretion of discount) amortization of premium on investments	(29)	(657)
Income tax benefit from release of valuation allowance	0	(335)
Provision for accounts receivable allowance	(1,004)	522
Net loss on investments	0	1,561
Other	(98)	(117)
Changes in operating assets and liabilities:
Accounts receivable	63,943	(10,067)
Inventory	2,221	(34,857)
Deferred costs with suppliers	430	28,179
Other assets	(1,176)	251
Contract origination costs, net	(356)	(802)
Project assets	(390)	(1,402)
Accounts payable	(16,280)	28,831
Accrued expenses and other liabilities	1,731	(31,746)
Deferred revenue	2,715	9,921
Lease liabilities	(807)	(593)
Net cash used in operating activities	(621)	(35,821)
INVESTING ACTIVITIES
Acquisitions, net of cash acquired	0	(1,847)
Purchase of available-for-sale investments	0	(49,152)
Proceeds from maturities of available-for-sale investments	8,250	50,270
Proceeds from sales of available-for-sale investments	0	73,917
Purchase of energy storage systems	(51)	(1,625)
Capital expenditures on internally-developed software	(3,463)	(3,570)
Purchase of property and equipment	(61)	(162)
Net cash provided by investing activities	4,675	67,831
FINANCING ACTIVITIES
Proceeds from exercise of stock options and warrants	0	149
Proceeds from employee equity transactions to be remitted to tax authorities, net	5,228	0
Repayment of financing obligations	(2,086)	(2,133)
Redemption of investment from non-controlling interests, net	0	(72)
Repayment of notes payable	0	(100)
Net cash provided by (used in) financing activities	3,142	(2,156)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	233	126
Net increase in cash, cash equivalents and restricted cash	7,429	29,980
Cash, cash equivalents and restricted cash, beginning of year	106,475	87,903
Cash, cash equivalents and restricted cash, end of period	113,904	117,883
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid for interest	1,422	1,481
NON-CASH INVESTING AND FINANCING ACTIVITIES
Change in asset retirement costs and asset retirement obligation	38	99
Purchases of energy storage systems in accounts payable	251	88
Right-of-use asset obtained in exchange for lease liability	0	2,782
Stock-based compensation capitalized to internal-use software	992	906
Stock issued for employee bonuses	7,523	0
RECONCILIATION OF CASH, CASH EQUIVALENTS, AND RESTRICTED CASH WITHIN THE CONDENSED CONSOLIDATED BALANCE SHEETS TO THE AMOUNTS SHOWN IN THE STATEMENTS OF CASH FLOWS ABOVE:
Cash and cash equivalents	112,804	117,883
Restricted cash included in other noncurrent assets	1,100	0
Total cash, cash equivalents, and restricted cash	$ 113,904	$ 117,883

BUSINESS

BUSINESS	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
BUSINESS	BUSINESS Description of the Business Stem, Inc. (“Stem,” the “Company,” “we,” “us,” or “our”) is a global leader in artificial intelligence (“AI”)-driven clean energy solutions and services. We maintain one of the world’s largest digitally connected, intelligent, renewable energy networks, providing customers with (i) energy storage hardware, sourced from leading, global battery original equipment manufacturers (“OEMs”), that we deliver through our partners, including developers, distributors and engineering, procurement and construction (“EPC”) firms, (ii) edge hardware to aid in the collection of site data and the real-time operation and control of the site plus other optional equipment, and (iii) an ongoing software platform, Athena®, and services to operate and manage the performance of standalone energy storage, integrated solar plus storage systems, and solar assets. In addition, in all of the markets where we help manage our customers’ clean energy assets, we have agreements to use the Athena platform to participate in such markets and to share the revenue from such market participation. We deliver our battery hardware and software-enabled services to customers through our Athena platform. The Company’s hardware and recurring software-enabled services mitigate customer energy costs through services such as time-of-use and demand charge management optimization and by aggregating the dispatch of energy through a network of virtual power plants. The network created by the Company’s growing customer base increases grid resilience and reliability through the real-time processing of market-based demand signals, energy prices, and other factors in connection with the deployment of renewable energy resources to such customers. Additionally, the Company’s clean energy solutions are designed to support renewable energy generation by helping to alleviate grid intermittency issues, thereby reducing customer dependence on traditional, fossil fuel resources. The Company’s Athena PowerTrack application provides a vertically integrated solution that incorporates on-site power monitoring equipment that aggregates and communicates data to enable remote control of solar generation assets. PowerTrack provides direct access to individual site performance to measure and benchmark expected energy production, maximizing asset value for the Company’s customers. From time to time, the Company, through an indirect wholly-owned development subsidiary (“DevCo”) will enter into strategic joint ventures (each a “DevCo JV”) with qualified third parties for the development of select renewable energy projects (“DevCo Projects”). In this structure, DevCo forms a new DevCo JV entity as the majority owner, with the developer as the minority owner. The purpose of the DevCo JV is to develop and sell DevCo Projects and secure Company hardware and software services for those projects. In DevCo Projects, the Company makes development capital contributions to fund project development, and recovers those capital contributions plus a fee when the developer takes ownership of the project. This business model is intended to allow the Company to advance development capital to key partners in strategic markets and secure hardware upfront, in order to generate higher-margin software and services and other revenue via exclusive long-term services contracts under the DevCo Projects. The Company operated as Rollins Road Acquisition Company (f/k/a Stem, Inc.) (“Legacy Stem”) prior to the Merger with Star Peak Transition Corp. (“STPK”), an entity that was then listed on the New York Stock Exchange under the trade symbol “STPK,” and STPK Merger Sub Corp., a Delaware corporation and wholly-owned subsidiary of STPK (“Merger Sub”), providing for, among other things, and subject to the conditions therein, the combination of the Company and STPK pursuant to the merger of Merger Sub with and into the Company, with the Company continuing as the surviving entity (the “Merger”). Stem, Inc. was incorporated on March 16, 2009 in the State of Delaware and is headquartered in San Francisco, California. Liquidity As of March 31, 2024, we had cash and cash equivalents of $112.8 million, an accumulated deficit of $844.8 million, net accounts receivable of $239.9 million, and working capital, which we define as current assets less current liabilities, of $168.9 million. During the three months ended March 31, 2024, we incurred a net loss of $72.3 million and had negative cash flows from operating activities of $0.6 million. As of March 31, 2024, our principal sources of liquidity were cash and cash equivalents totaling $112.8 million, which were held for working capital purposes and for investment growth opportunities. As of March 31, 2024, we believe that our cash position, as well as expected collections from accounts receivable, is sufficient to meet capital and liquidity requirements for at least the next 12 months from the date of this Quarterly Report on Form 10-Q. Our business prospects are subject to risks, expenses, and uncertainties frequently encountered by companies in the early stages of commercial operations. The attainment of profitable operations is dependent upon future events, including securing new customers and maintaining current ones, securing and maintaining adequate supplier relationships, building our customer base, successfully executing our business and marketing strategy, obtaining adequate financing to complete our development activities, and hiring and retaining appropriate personnel. Failure to generate sufficient revenues, achieve planned gross margins and operating profitability, control operating costs, or secure additional funding may require us to modify, delay or abandon some of our planned future expansion or development, or to otherwise enact operating cost reductions available to management, which could have a material adverse effect on our business, operating results and financial condition. Supply Chain Constraints and Risk We have in the past faced shortages and shipping delays affecting the supply of inverters, enclosures, battery modules and associated component parts for inverters and battery energy storage systems available for purchase. These shortages and delays were due in part to the evolving macroeconomic, geopolitical and business environment, including the effects of global inflationary pressures and interest rates, general economic slowdown or a recession, changes in monetary policy, instability in financial institutions, potential import tariffs, geopolitical pressures, including the armed conflicts between Russia and Ukraine and in the Gaza Strip and nearby areas, as well as tensions between China and the United States and unknown effects of current and future trade regulations. We cannot predict the full effects the macroeconomic, geopolitical and business environment will have on our business, cash flows, liquidity, financial condition and results of operations.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim reporting and with the instructions to Form 10-Q and Article 10 of Regulation S-X, assuming the Company will continue as a going concern. Accordingly, the consolidated balance sheet at December 31, 2023 has been derived from the audited financial statements at that date, but certain notes or other information that are normally required by GAAP have been omitted if they substantially duplicate the disclosures contained in the Company’s annual audited consolidated financial statements. In the opinion of the Company’s management, all normal and recurring adjustments considered necessary for a fair statement of the results for the interim period presented have been included in the accompanying unaudited condensed consolidated financial statements. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited financial statements for the year ended December 31, 2023. Operating results for the three months ended March 31, 2024 are not necessarily indicative of the results that may be expected for the year ending December 31, 2024 or for any other future interim period or year. Principles of Consolidation The unaudited condensed consolidated financial statements include the accounts of the Company, its wholly-owned subsidiaries, and consolidated variable interest entities (“VIEs”). The Company presents non-controlling interests within the equity section of its condensed consolidated balance sheets, and the amount of consolidated net loss that is attributable to the Company and the non-controlling interest in its condensed consolidated statements of operations. All intercompany balances and transactions have been eliminated in consolidation. Variable Interest Entities The Company forms special purpose entities (“SPEs”), some of which are VIEs, with its investors in the ordinary course of business to facilitate the funding and monetization of its energy storage systems. A legal entity is considered a VIE if it has either a total equity investment that is insufficient to finance its operations without additional subordinated financial support or whose equity holders lack the characteristics of a controlling financial interest. The Company’s variable interests arise from contractual, ownership, or other monetary interests in the entity. The typical condition for a controlling financial interest ownership is holding a majority of the voting interests of an entity; however, a controlling financial interest may also exist in entities, such as VIEs, through arrangements that do not involve controlling voting interests. The Company consolidates a VIE if it is deemed to be the primary beneficiary. The Company determines it is the primary beneficiary if it has the power to direct the activities that most significantly impact the VIEs’ economic performance and has the obligation to absorb losses or has the right to receive benefits of the VIE that could potentially be significant to the VIE. The Company evaluates its relationships with its VIEs on an ongoing basis to determine whether it is the primary beneficiary. Beginning in January 2022, the Company formed DevCo JVs with the purpose of originating potential battery storage facility projects in specific locations and conducting early-stage planning and development activities. The Company determined that the DevCo JVs are VIEs, as they lack sufficient equity to finance their activities without additional financial support. The Company determined that it has both (1) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance, and (2) the obligation to absorb losses or receive benefits from the VIE that could potentially be significant. Accordingly, the Company has determined that it is the primary beneficiary of the DevCo JVs, and as a result, the DevCo JVs’ operating results, assets and liabilities are consolidated by the Company, with third party minority owners’ share presented as noncontrolling interest. The Company applied the hypothetical liquidation at book value method in allocating recorded net income (loss) to each owner based on the change in the reporting period, of the amount of net assets of the entity to which each owner would be entitled to under the governing contracts in a liquidation scenario. The following table summarizes the carrying values of the assets and liabilities of the DevCo JVs that are consolidated by the Company as of March 31, 2024 and December 31, 2023 (in thousands): March 31, 2024 December 31, 2023 Assets Cash and cash equivalents $ 791 $ 2,191 Other current assets 22 30 Other noncurrent assets 8,469 8,424 Total assets 9,282 10,645 Liabilities Accounts payable 2,107 1,405 Other current liabilities 197 1,892 Total liabilities $ 2,304 $ 3,297 The Company did not make any material capital investment contributions during the three months ended March 31, 2024. For the three months ended March 31, 2023, the Company contributed approximately $0.1 million in capital investments for hardware purchases. The net income from the DevCo JVs was immaterial during both the three months ended March 31, 2024 and March 31, 2023. Use of Estimates The preparation of unaudited condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates on historical experience and on various other assumptions believed to be reasonable. Actual results could differ from those estimates and such differences could be material to the financial position and results of operations. Significant estimates and assumptions reflected in these unaudited condensed consolidated financial statements include, but are not limited to, depreciable life of energy storage systems; estimates of transaction price with variable consideration; the amortization of acquired intangibles; the amortization of financing obligations; deferred commissions and contract fulfillment costs; the valuation of energy storage systems, finite-lived intangible assets, internally developed software, and asset retirement obligations; and the fair value of equity instruments, equity-based instruments, derivative liability, accruals related to sales tax liabilities and the fair value of assets acquired and liabilities assumed in a business combination. Segment Information Operating segments are defined as components of an entity for which discrete financial information is available that is regularly reviewed by the Chief Operating Decision Maker (“CODM”) in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s Chief Executive Officer is the CODM. The CODM reviews financial information presented on a consolidated basis for purposes of making operating decisions, allocating resources, and evaluating financial performance. As such, management has determined that the Company operates as one operating segment that is focused exclusively on innovative technology services that transform the way energy is distributed and consumed. Net assets outside of the U.S. were less than 10% of total net assets as of March 31, 2024 and December 31, 2023. Concentration of Credit Risk and Other Uncertainties Financial instruments that potentially subject the Company to concentration of credit risk consist of cash and cash equivalents and accounts receivable. The Company’s cash balances are primarily invested in money market funds or on deposit at high credit quality financial institutions in the U.S. The Company’s cash and cash equivalents are held at financial institutions where account balances may at times exceed federally insured limits. Management believes the Company is not exposed to significant credit risk due to the financial strength of the depository institution in which the cash is held. The Company has no financial instruments with off-balance sheet risk of loss. At times, the Company may be subject to a concentration of credit risk in relation to certain customers due to the purchase of large energy storage systems made by such customers. The Company routinely assesses the creditworthiness of its customers. The Company has not experienced material losses related to receivables from individual customers, or groups of customers during the three months ended March 31, 2024 and 2023 . The Company does not require collateral. Due to these factors, no additional credit risk beyond amounts provided for credit losses is believed by management to be probable in the Company ’s accounts receivable. Significant Customers A significant customer represents 10% or more of the Company’s total revenue or accounts receivable, net balance at each reporting date. For each significant customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable are as follows: Accounts Receivable Revenue March 31, December 31, Three Months Ended March 31, 2024 2023 2024 2023 Customers: Customer A 50 % 41 % 24 % * Customer B 17 % 28 % * 61 % Customer C * * 22 % * Customer D * * 22 % * *Total less than 10% for the period. There are inherent risks whenever a large percentage of total revenue is concentrated in a limited number of customers. Should a significant customer terminate or fail to renew its contracts with us, in whole or in part, for any reason, or experience significant financial or operating difficulties, it could have a material adverse effect on our financial condition and results of operations. In general, a customer that makes up a significant portion of revenues in one period, may not make up a significant portion in subsequent periods. Fair Value of Financial Instruments Assets and liabilities recorded at fair value in the unaudited condensed consolidated financial statements are categorized based upon the level of judgment associated with the inputs used to measure their fair value. The fair value of the Company’s financial assets and liabilities reflects management’s estimate of amounts that the Company would have received in connection with the sale of the assets or paid in connection with the transfer of the liabilities in an orderly transaction between market participants at the measurement date. In connection with measuring the fair value of its assets and liabilities, the Company seeks to maximize the use of observable inputs (market data obtained from independent sources) and to minimize the use of unobservable inputs (internal assumptions about how market participants would price assets and liabilities). Hierarchical levels which are directly related to the amount of subjectivity associated with the inputs to the valuation of these assets or liabilities are as follows: Level 1 — Unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access as of the measurement date. Level 2 — Inputs other than quoted prices included within Level 1 that are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. Level 3 — Unobservable inputs for the asset or liability only used when there is little, if any, market activity for the asset or liability at the measurement date. This hierarchy requires the Company to use observable market data, when available, and to minimize the use of unobservable inputs when determining fair value. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to their fair value measurement. The Company’s assessment of the significance of a specific input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. Financial assets and liabilities held by the Company measured at fair value on a recurring basis as of March 31, 2024 and December 31, 2023 include cash and cash equivalents, short-term investments, derivative liability, and convertible notes.

REVENUE

REVENUE	3 Months Ended
	Mar. 31, 2024
Revenue from Contract with Customer [Abstract]
REVENUE	REVENUE Disaggregation of Revenue The following table provides information on the disaggregation of revenue as recorded in the condensed consolidated statements of operations (in thousands): Three Months Ended 2024 2023 Hardware revenue $ 10,629 $ 52,732 Services and other revenue 14,840 14,673 Total revenue $ 25,469 $ 67,405 The following table summarizes reportable revenue by geographic regions determined based on the location of the customers (in thousands): Three Months Ended 2024 2023 United States $ 24,294 $ 65,330 Rest of the world 1,175 2,075 Total revenue $ 25,469 $ 67,405 Remaining Performance Obligations Remaining performance obligations represent contracted revenue that has not been recognized, which include contract liabilities (deferred revenue) and amounts that will be billed and recognized as revenue in future periods. As of March 31, 2024 and March 31, 2023, the Company had $440.6 million and $541.1 million of remaining performance obligations, respectively, and the approximate percentages expected to be recognized as revenue in the future are as follows (in thousands, except percentages): March 31, 2024 Total Remaining Percent Expected to be Recognized as Revenue Less Than Two to Greater Than Services and other revenue $ 344,555 15 % 47 % 38 % Hardware revenue 96,013 96 % 4 % — % Total revenue $ 440,568 March 31, 2023 Total Remaining Percent Expected to be Recognized as Revenue Less Than Two to Greater Than Services and other revenue $ 327,149 14 % 48 % 38 % Hardware revenue 213,993 100 % — % — % Total revenue $ 541,142 Contract Balances Deferred revenue primarily includes cash received in advance of revenue recognition related to energy optimization services and incentives. The following table presents the changes in the deferred revenue balance during the three months ended March 31, 2024 and March 31, 2023 (in thousands): Three Months Ended March 31, 2024 2023 Beginning balance $ 142,647 $ 138,074 Upfront payments received from customers 17,373 30,700 Upfront or annual incentive payments received 497 1,275 Revenue recognized related to amounts that were included in beginning balance of deferred revenue (10,074) (8,463) Revenue recognized related to deferred revenue generated during the period (5,081) (13,591) Ending balance $ 145,362 $ 147,995 Parent Company Guarantees Prior to July 2023, the Company agreed in certain customer contracts to provide a guarantee that the value of purchased hardware will not decline for a certain period of time. Under this guarantee, if these customers were unable to install or designate the hardware to a specified project within such period of time, the Company would be required to assist the customer in re-marketing the hardware for resale by the customer. If a resale does not occur, the hardware will be appraised utilizing a third party. The guarantee provided that, in such cases, if the customer resold the hardware for less than the amount initially sold to the customer or the appraisal value is less than the hardware purchase price, the Company would be required to compensate the customer for any shortfall in fair value for the hardware from the initial contract price. The Company accounts for such contractual terms and guarantees as variable consideration at each measurement date. The Company updates its estimate of variable consideration each quarter, including changes in estimates related to such guarantees, for facts or circumstances that have changed from the time of the initial estimate. As a result, the Company recorded a net revenue reduction of $33.1 million in hardware revenue during the three months ended March 31, 2024. The overall reduction in revenue was related to deliveries that occurred prior to the current fiscal year. The remaining net book value of the billed and unbilled receivable as of March 31, 2024 is $108.1 million which could be subject to further adjustments under the guarantee.

SHORT-TERM INVESTMENTS

SHORT-TERM INVESTMENTS	3 Months Ended
	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
SHORT-TERM INVESTMENTS	SHORT-TERM INVESTMENTS The Company did not have short-term investments as of March 31, 2024. The following tables summarize the estimated fair value of the Company’s short-term investments and the gross unrealized holding gains and losses as of December 31, 2023 (in thousands). As of December 31, 2023 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Commercial paper $ 1,978 $ — $ — $ 1,978 U.S. government bonds 2,744 — (3) 2,741 Agency bonds 3,503 — (3) 3,500 Total short-term investments $ 8,225 $ — $ (6) $ 8,219

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS Fair value accounting is applied for all financial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis. On March 31, 2024 and December 31, 2023, the carrying amount of accounts receivable, other current assets, accounts payable, and accrued and other current liabilities approximated their estimated fair value due to their relatively short maturities. Assets and Liabilities Measured at Fair Value on a Recurring Basis The following table provides the financial instruments measured at fair value (in thousands): March 31, 2024 Level 1 Level 2 Level 3 Fair Value Assets: Cash equivalents: Money market fund $ 60,378 $ — $ — $ 60,378 Total financial assets $ 60,378 $ — $ — $ 60,378 Liabilities: Derivative liability $ — $ — $ 7,731 $ 7,731 December 31, 2023 Level 1 Level 2 Level 3 Fair Value Assets: Cash equivalents: Money market fund $ 47,297 $ — $ — $ 47,297 Commercial paper — 3,971 — 3,971 Debt securities: Commercial paper — 1,978 — 1,978 U.S. government bonds — 2,741 — 2,741 Other — 3,500 — 3,500 Total financial assets $ 47,297 $ 12,190 $ — $ 59,487 Liabilities: Derivative liability $ — $ — $ 7,731 $ 7,731 The Company’s money market funds are classified as Level 1 because they are valued using quoted market prices. The Company’s short-term investments consist of available-for-sale securities and are classified as Level 2 because their value is based on valuations using significant inputs derived from or corroborated by observable market data. The Company’s other current liabilities includes a derivative liability that is attributable to a derivative feature within a revenue contract, whereby final settlement is indexed to the price per ton of lithium carbonate. The balance was valued using a third party forecast for lithium carbonate. As the derivative instrument is not traded on an exchange they are classified within Level 3 of the fair value hierarchy. Fair Value of Convertible Promissory Notes The convertible notes are recorded at face value less unamortized debt issuance costs (see Note 8 — Convertible Notes for additional details) on the condensed consolidated balance sheets as of March 31, 2024. As of March 31, 2024 and December 31, 2023, the estimated fair value of the 2028 Convertible Notes was $144.1 million and $149.1 million, respectively, based on Level 2 quoted bid prices of the convertible notes in an over-the-counter market on the last trading date of the reporting period. As of March 31, 2024 and December 31, 2023, the estimated fair value of the 2030 Convertible Notes was $125.7 million and $175.8 million , respectively , based on Level 2 quoted bid prices of the convertible notes in an over-the-counter market on the last trading date of the reporting period.

GOODWILL AND INTANGIBLE ASSETS,

GOODWILL AND INTANGIBLE ASSETS, NET	3 Months Ended
	Mar. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND INTANGIBLE ASSETS, NET	GOODWILL AND INTANGIBLE ASSETS, NET Goodwill Goodwill consists of the following (in thousands): March 31, December 31, 2024 2023 Goodwill $ 547,158 $ 547,158 Effect of foreign currency translation 11 47 Total goodwill $ 547,169 $ 547,205 Intangible Assets, Net Intangible assets, net, consists of the following (in thousands): March 31, December 31, 2024 2023 Developed technology $ 32,618 $ 32,618 Trade name 11,300 11,300 Customer relationships 106,800 106,800 Internally developed software 71,738 67,282 Intangible assets 222,456 218,000 Less: Accumulated amortization (67,451) (60,868) Add: Currency translation adjustment 3 14 Total intangible assets, net $ 155,008 $ 157,146 Amortization expense for intangible assets was $6.6 million and $6.5 million for the three months ended March 31, 2024 and 2023, respectively .

ENERGY STORAGE SYSTEMS, NET

ENERGY STORAGE SYSTEMS, NET	3 Months Ended
	Mar. 31, 2024
Property, Plant and Equipment [Abstract]
ENERGY STORAGE SYSTEMS, NET	ENERGY STORAGE SYSTEMS, NET Energy Storage Systems, Net Energy storage systems, net, consists of the following (in thousands): March 31, December 31, 2024 2023 Energy storage systems placed into service $ 139,083 $ 141,181 Less: accumulated depreciation (71,800) (70,918) Energy storage systems not yet placed into service 3,951 4,155 Total energy storage systems, net $ 71,234 $ 74,418 Depreciation expense for energy storage systems was approximately $3.0 million and $3.6 million for the three months ended March 31, 2024 and 2023, respectively. Depreciation expense is recognized in cost of services and other revenue. Impairment expense for energy storage systems was approximately $0.9 million for the three months ended March 31, 2023. The Company did not recognize impairment expense for the three months ended March 31, 2024. Impairment expense is recognized in cost of services and other revenue.

CONVERTIBLE NOTES

CONVERTIBLE NOTES	3 Months Ended
	Mar. 31, 2024
Debt Disclosure [Abstract]
CONVERTIBLE NOTES	CONVERTIBLE NOTES 2028 Convertible Notes and 2028 Capped Call Options 2028 Convertible Notes On November 22, 2021, the Company issued $460.0 million aggregate principal amount of its 2028 Convertible Notes in a private placement offering to qualified institutional buyers (the “2021 Initial Purchasers”) pursuant to Rule 144A under the Securities Act of 1933, as amended. The 2028 Convertible Notes are senior, unsecured obligations of the Company and bear interest at a rate of 0.5% per year, payable in cash semi-annually in arrears in June and December of each year, beginning in June 2022. The 2028 Convertible Notes will mature on December 1, 2028, unless earlier repurchased, redeemed or converted in accordance with their terms prior to such date. Upon conversion, the Company may choose to pay or deliver, as the case may be, cash, shares of common stock or a combination of cash and shares of common stock. The 2028 Convertible Notes are redeemable for cash at the Company’s option at any time given certain conditions (as discussed below), at an initial conversion rate of 34.1965 shares of common stock per $1,000 principal amount of 2028 Convertible Notes, which is equivalent to an initial conversion price of approximately $29.24 (the “2028 Conversion Price”) per share of the Company’s common stock. The conversion rate is subject to customary adjustments for certain events as described in the related indenture. The Company may redeem for cash all or any portion of the 2028 Convertible Notes, at the Company’s option, on or after December 5, 2025 if the last reported sale price of the Company’s common stock has been at least 130% of the 2028 Conversion Price then in effect for at least 20 trading days at a redemption price equal to 100% of the principal amount of the 2028 Convertible Notes to be redeemed, plus accrued and unpaid interest. The Company’s net proceeds from this offering were approximately $445.7 million , after deducting the 2021 Initial Purchasers’ discounts and debt issuance costs. To minimize the effect of potential dilution to the Company’s common stockholders upon conversion of the 2028 Convertible Notes, the Company entered into separate capped call transactions (the “2028 Capped Calls”) as described below. In connection with the issuance of the 2030 Convertible Notes during the second quarter of 2023, t he Company used approximately $99.8 million of the net proceeds to purchase and surrender for cancellation approximately $163.0 million aggregate principal amount of the Company’s 2028 Convertible Notes, which resulted in a $59.4 million gain on debt extinguishment. See 2030 Convertible Notes below for further details of the 2030 Convertible Notes . Upon adoption of ASU 2020-06, the Company allocated all of the debt discount to long-term debt. The debt discount is amortized to interest expense using the effective interest method, computed to be 0.9%, over the life of the 2028 Convertible Notes or approximately its seven-year term. The outstanding 2028 Convertible Notes balances as of March 31, 2024 and December 31, 2023 are summarized in the following table (in thousands): March 31, 2024 December 31, 2023 Long Term Debt Outstanding principal $ 297,024 $ 297,024 Unamortized 2021 Initial Purchasers’ debt discount and debt issuance cost (6,177) (6,501) Net carrying amount $ 290,847 $ 290,523 The following table presents total interest expense recognized related to the 2028 Convertible Notes during the three months ended March 31, 2024 and 2023 (in thousands) : Three Months Ended 2024 2023 Cash interest expense Contractual interest expense $ 371 $ 575 Non-cash interest expense Amortization of debt discount and debt issuance cost 324 499 Total interest expense $ 695 $ 1,074 2028 Capped Call Options On November 17, 2021, in connection with the pricing of the 2028 Convertible Notes, and on November 19, 2021, in connection with the exercise in full by the 2021 Initial Purchasers of their option to purchase additional Notes, the Company entered into the 2028 Capped Calls with certain counterparties. The Company used $66.7 million of the net proceeds to pay the cost of the 2028 Capped Calls. The 2028 Capped Calls have an initial strike price of $29.2428 per share, which corresponds to the initial conversion price of the 2028 Convertible Notes and is subject to anti-dilution adjustments. The 2028 Capped Calls have a cap price of $49.6575 per share, subject to certain adjustments. The 2028 Capped Calls are considered separate transactions entered into by and between the Company and the 2028 Capped Calls counterparties, and are not part of the terms of the 2028 Convertible Notes. The Company recorded a reduction to additional paid-in capital of $66.7 million during the year ended December 31, 2021 related to the premium payments for the 2028 Capped Calls. These instruments meet the conditions outlined in Financial Accounting Standards Board (“FASB”) ASU 2022-01 Topic 815, Derivatives and Hedging (“ASC 815”) to be classified in stockholders’ equity and are not subsequently remeasured as long as the conditions for equity classification continue to be met. 2030 Convertible Notes and 2030 Capped Call Options 2030 Convertible Notes On April 3, 2023, the Company issued $240.0 million aggregate principal amount of its 2030 Convertible Notes in a private placement offering to qualified institutional buyers (the “2023 Initial Purchasers”) pursuant to Rule 144A under the Securities Act of 1933, as amended. The 2030 Convertible Notes are senior, unsecured obligations of the Company and bear interest at a rate of 4.25% per year, payable in cash semi-annually in arrears in April and October of each year, beginning on October 1, 2023. The 2030 Convertible Notes will mature on April 1, 2030, unless earlier repurchased, redeemed or converted in accordance with their terms prior to such date. Upon conversion, the Company may choose to pay or deliver cash, shares of common stock or a combination of cash and shares of common stock. The 2030 Convertible Notes are redeemable for cash at the Company’s option at any time given certain conditions (as discussed below), at an initial conversion rate of 140.3066 shares of common stock per $1,000 principal amount of the 2030 Convertible Notes, which is equivalent to an initial conversion price of approximately $7.1272 (the “2030 Conversion Price”) per share of the Company’s common stock. The conversion rate is subject to customary adjustments for certain events as described in the related indenture. The 2030 Convertible Notes will be redeemable, in whole or in part, at the Company’s option, on or after April 5, 2027 if the last reported sale price of the Company’s common stock has been at least 130% of the 2030 Conversion Price then in effect for at least 20 trading days at a redemption price equal to 100% of the principal amount of the 2030 Convertible Notes to be redeemed, plus accrued and unpaid interest. The Company’s net proceeds from this offering were approximately $232.4 million, net of $7.6 million in debt issuance costs primarily consisting of underwriters, advisory, legal, and accounting fees. The Company used approximately $99.8 million of the net proceeds to purchase and surrender for cancellation approximately $163.0 million aggregate principal amount of the Company’s 2028 Convertible Notes. See 2028 Convertible Notes above for further details on the impacts of the debt extinguishment. The outstanding 2030 Convertible Notes balances as of March 31, 2024 and December 31, 2023 are summarized in the following table (in thousands): March 31, 2024 December 31, 2023 Long Term Debt Outstanding principal $ 240,000 $ 240,000 Unamortized 2023 Initial Purchasers’ debt discount and debt issuance cost (6,647) (6,890) Net carrying amount $ 233,353 $ 233,110 The debt discount and debt issuance costs are amortized to interest expense using the effective interest method, computed to be 4.70%, over the life of the 2030 Convertible Notes or its approximately seven-year term. The following table presents total interest expense recognized related to the 2030 Convertible Notes during the three months ended March 31, 2024 (in thousands) : Three Months Ended Cash interest expense Contractual interest expense $ 2,550 Non-cash interest expense Amortization of debt discount and debt issuance cost 243 Total interest expense $ 2,793 2030 Capped Call Options On March 29, 2023 and March 31, 2023, in connection with the pricing of the 2030 Convertible Notes, and on April 3, 2023, in connection with the exercise in full by the 2023 Initial Purchasers of their option to purchase additional 2030 Convertible Notes, the Company entered into Capped Calls (the “2030 Capped Calls”) with certain counterparties. The Company used $27.8 million of the net proceeds from the 2030 Convertible Notes to pay the cost of the 2030 Capped Calls. The 2030 Capped Calls have an initial strike price of $7.1272 per share, which corresponds to the initial conversion price of the 2030 Convertible Notes and is subject to anti-dilution adjustments. The 2030 Capped Calls have a cap price of $11.1800 per share, subject to certain adjustments. The 2030 Capped Calls are considered separate transactions entered into by and between the Company and the 2030 Capped Calls counterparties, and are not part of the terms of the 2030 Convertible Notes. The Company recorded a reduction to additional paid-in capital of $27.8 million during the second quarter of 2023 related to the premium payments for the 2030 Capped Calls. These instruments meet the conditions outlined in ASC 815 to be classified in stockholders’ equity and are not subsequently remeasured as long as the conditions for equity classification continue to be met.

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	3 Months Ended
	Mar. 31, 2024
Share-Based Payment Arrangement [Abstract]
STOCK-BASED COMPENSATION	STOCK-BASED COMPENSATION Equity Incentive Plans Under both the Stem, Inc. 2009 Equity Incentive Plan (the “2009 Plan”) and the Stem, Inc. 2021 Equity Incentive Plan (the “2021 Plan,” and together with the 2009 Plan, the “Plans”), the Company may grant stock options, stock appreciation rights, restricted stock, restricted stock units (“RSUs”), performance stock units (“PSUs”), and other awards that are settled in shares of the Company’s common stock. The Company does not intend to grant new awards under the 2009 Plan. All shares that remain available for future grants are under the 2021 Plan. Stock Options The following table summarizes the stock option activity for the period ended March 31, 2024: Number of Weighted- Weighted- Aggregate Balances as of December 31, 2023 9,011,616 $ 6.99 6.0 $ 8,686 Options granted 687,483 3.37 Options forfeited and expired (26,465) 30.26 Balances as of March 31, 2024 9,672,634 $ 6.67 6.0 $ 1,822 Options vested and exercisable — March 31, 2024 7,066,446 $ 5.31 5.1 $ 1,821 As of March 31, 2024, the Company had approximately $14.2 million of remaining unrecognized stock-based compensation expense for stock options, which is expected to be recognized over a weighted average period of 1.4 years. Restricted Stock Units The following table summarizes the RSU activity for the period ended March 31, 2024: Number of RSUs Outstanding (1) Weighted-Average Balances as of December 31, 2023 11,159,272 $ 10.31 RSUs granted 3,378,189 2.76 RSUs vested (5,593,662) 4.32 RSUs forfeited (450,663) 6.53 Balances as of March 31, 2024 8,493,136 $ 11.30 (1) Includes certain restricted stock units with service and market-based vesting criteria. As of March 31, 2024, the Company had approximately $60.4 million of remaining unrecognized stock-based compensation expense for RSUs, which is expected to be recognized over a weighted average period of 1.8 years. Stock-Based Compensation Expense The following table summarizes stock-based compensation expense recorded in each component of operating expenses in the Company’s condensed consolidated statements of operations and comprehensive loss (in thousands): Three Months Ended 2024 2023 Sales and marketing $ 1,114 $ 945 Research and development 1,531 1,718 General and administrative 5,729 4,539 Total stock-based compensation expense $ 8,374 $ 7,202 Stock-based compensation expense associated with research and development of $1.0 million and $0.9 million were capitalized as internal-use software during the three months ended March 31, 2024 and 2023, respectively.

NET LOSS PER SHARE

NET LOSS PER SHARE	3 Months Ended
	Mar. 31, 2024
Earnings Per Share [Abstract]
NET LOSS PER SHARE	NET LOSS PER SHARE The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders (in thousands, except share and per share amounts): Three Months Ended 2024 2023 Numerator: Net loss attributable to common stockholders $ (72,307) $ (44,778) Denominator: Weighted-average number of shares outstanding used to compute net loss per share attributable to common stockholders, basic and diluted 158,180,137 154,966,163 Net loss per share attributable to common stockholders, basic and diluted $ (0.46) $ (0.29) The following table shows total outstanding potentially dilutive shares excluded from the computation of diluted net loss per share attributable to common stockholders as their effect would have been anti-dilutive, as of March 31, 2024 and 2023: March 31, 2024 March 31, 2023 Outstanding 2028 Convertible Notes (if converted) 10,157,181 15,730,390 Outstanding 2030 Convertible Notes (if converted) 33,673,584 — Outstanding stock options 9,672,634 9,314,976 Outstanding warrants 2,533 2,533 Outstanding RSUs 8,493,136 7,204,114 Total 61,999,068 32,252,013

INCOME TAXES

INCOME TAXES	3 Months Ended
	Mar. 31, 2024
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The following table reflects the Company’s (provision for) benefit from income taxes and the effective tax rates for the periods presented below (in thousands, except effective tax rate): Three Months Ended March 31, 2024 2023 Loss before (provision for) benefit from income taxes $ (72,154) $ (44,869) (Provision for) benefit from income taxes $ (153) $ 91 Effective tax rate (0.2) % 0.2 % For the three months ended March 31, 2024 , the Company recognized a provision for income taxes of $0.2 million , representing an effective tax rate of (0.2)%, which was lower than the statutory federal tax rate because the Company maintains a valuation allowance on its U.S. deferred tax assets. For the three months ended March 31, 2023, the Company recognized a benefit from income taxes of $0.1 million , representing an effective tax rate of 0.2%, which was lower than the statutory federal tax rate due to a $0.3 million tax benefit from an acquisition for a partial valuation allowance release on U.S. deferred tax assets due to the deferred tax liability established in purchase accounting on acquired intangibles during the three months ended March 31, 2023 .

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Contingencies The Company is party to various legal proceedings from time to time. A liability is accrued when a loss is both probable and can be reasonably estimated. Management believes that the probability of a material loss with respect to any currently pending legal proceeding is remote. However, litigation is inherently uncertain and it is not possible to definitively predict the ultimate disposition of any of these proceedings. As of the date of this filing, the Company does not believe that there are any pending legal proceedings or other loss contingencies that will, either individually or in the aggregate, have a material adverse effect on the Company taken as a whole. Non-cancelable Purchase Obligations During the three months ended March 31, 2024, there have been no material changes to our non-cancelable purchase obligations from those disclosed in Note 20. “Commitments and Contingencies” in the notes to consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2023, filed with the SEC on February 29, 2024. Non-Income Related Taxes

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Mar. 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

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim reporting and with the instructions to Form 10-Q and Article 10 of Regulation S-X, assuming the Company will continue as a going concern. Accordingly, the consolidated balance sheet at December 31, 2023 has been derived from the audited financial statements at that date, but certain notes or other information that are normally required by GAAP have been omitted if they substantially duplicate the disclosures contained in the Company’s annual audited consolidated financial statements. In the opinion of the Company’s management, all normal and recurring adjustments considered necessary for a fair statement of the results for the interim period presented have been included in the accompanying unaudited condensed consolidated financial statements. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited financial statements for the year ended December 31, 2023. Operating results for the three months ended March 31, 2024 are not necessarily indicative of the results that may be expected for the year ending December 31, 2024 or for any other future interim period or year.
Principles of Consolidation	Principles of Consolidation
Variable Interest Entities	Variable Interest Entities The Company forms special purpose entities (“SPEs”), some of which are VIEs, with its investors in the ordinary course of business to facilitate the funding and monetization of its energy storage systems. A legal entity is considered a VIE if it has either a total equity investment that is insufficient to finance its operations without additional subordinated financial support or whose equity holders lack the characteristics of a controlling financial interest. The Company’s variable interests arise from contractual, ownership, or other monetary interests in the entity. The typical condition for a controlling financial interest ownership is holding a majority of the voting interests of an entity; however, a controlling financial interest may also exist in entities, such as VIEs, through arrangements that do not involve controlling voting interests. The Company consolidates a VIE if it is deemed to be the primary beneficiary. The Company determines it is the primary beneficiary if it has the power to direct the activities that most significantly impact the VIEs’ economic performance and has the obligation to absorb losses or has the right to receive benefits of the VIE that could potentially be significant to the VIE. The Company evaluates its relationships with its VIEs on an ongoing basis to determine whether it is the primary beneficiary.
Use of Estimates	Use of Estimates The preparation of unaudited condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates on historical experience and on various other assumptions believed to be reasonable. Actual results could differ from those estimates and such differences could be material to the financial position and results of operations. Significant estimates and assumptions reflected in these unaudited condensed consolidated financial statements include, but are not limited to, depreciable life of energy storage systems; estimates of transaction price with variable consideration; the amortization of acquired intangibles; the amortization of financing obligations; deferred commissions and contract fulfillment costs; the valuation of energy storage systems, finite-lived intangible assets, internally developed software, and asset retirement obligations; and the fair value of equity instruments, equity-based instruments, derivative liability, accruals related to sales tax liabilities and the fair value of assets acquired and liabilities assumed in a business combination.
Segment Information	Segment Information Operating segments are defined as components of an entity for which discrete financial information is available that is regularly reviewed by the Chief Operating Decision Maker (“CODM”) in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s Chief Executive Officer is the CODM. The CODM reviews financial information presented on a consolidated basis for purposes of making operating decisions, allocating resources, and evaluating financial performance. As such, management has determined that the Company operates as one
Concentration of Credit Risk and Other Uncertainties	Concentration of Credit Risk and Other Uncertainties Financial instruments that potentially subject the Company to concentration of credit risk consist of cash and cash equivalents and accounts receivable. The Company’s cash balances are primarily invested in money market funds or on deposit at high credit quality financial institutions in the U.S. The Company’s cash and cash equivalents are held at financial institutions where account balances may at times exceed federally insured limits. Management believes the Company is not exposed to significant credit risk due to the financial strength of the depository institution in which the cash is held. The Company has no financial instruments with off-balance sheet risk of loss. At times, the Company may be subject to a concentration of credit risk in relation to certain customers due to the purchase of large energy storage systems made by such customers. The Company routinely assesses the creditworthiness of its customers. The Company has not experienced material losses related to receivables from individual customers, or groups of customers during the three months ended March 31, 2024 and 2023 . The Company does not require collateral. Due to these factors, no additional credit risk beyond amounts provided for credit losses is believed by management to be probable in the Company ’s accounts receivable.
Significant Customers	Significant Customers
Fair Value of Financial Instruments	Fair Value of Financial Instruments Assets and liabilities recorded at fair value in the unaudited condensed consolidated financial statements are categorized based upon the level of judgment associated with the inputs used to measure their fair value. The fair value of the Company’s financial assets and liabilities reflects management’s estimate of amounts that the Company would have received in connection with the sale of the assets or paid in connection with the transfer of the liabilities in an orderly transaction between market participants at the measurement date. In connection with measuring the fair value of its assets and liabilities, the Company seeks to maximize the use of observable inputs (market data obtained from independent sources) and to minimize the use of unobservable inputs (internal assumptions about how market participants would price assets and liabilities). Hierarchical levels which are directly related to the amount of subjectivity associated with the inputs to the valuation of these assets or liabilities are as follows: Level 1 — Unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access as of the measurement date. Level 2 — Inputs other than quoted prices included within Level 1 that are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. Level 3 — Unobservable inputs for the asset or liability only used when there is little, if any, market activity for the asset or liability at the measurement date. This hierarchy requires the Company to use observable market data, when available, and to minimize the use of unobservable inputs when determining fair value. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to their fair value measurement. The Company’s assessment of the significance of a specific input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. Financial assets and liabilities held by the Company measured at fair value on a recurring basis as of March 31, 2024 and December 31, 2023 include cash and cash equivalents, short-term investments, derivative liability, and convertible notes.

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Schedule of Variable Interest Entities	The following table summarizes the carrying values of the assets and liabilities of the DevCo JVs that are consolidated by the Company as of March 31, 2024 and December 31, 2023 (in thousands): March 31, 2024 December 31, 2023 Assets Cash and cash equivalents $ 791 $ 2,191 Other current assets 22 30 Other noncurrent assets 8,469 8,424 Total assets 9,282 10,645 Liabilities Accounts payable 2,107 1,405 Other current liabilities 197 1,892 Total liabilities $ 2,304 $ 3,297
Schedule of Significant Customers	For each significant customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable are as follows: Accounts Receivable Revenue March 31, December 31, Three Months Ended March 31, 2024 2023 2024 2023 Customers: Customer A 50 % 41 % 24 % * Customer B 17 % 28 % * 61 % Customer C * * 22 % * Customer D * * 22 % * *Total less than 10% for the period.

REVENUE (Tables)

REVENUE (Tables)	3 Months Ended
	Mar. 31, 2024
Revenue from Contract with Customer [Abstract]
Schedule of Disaggregation of Revenue	The following table provides information on the disaggregation of revenue as recorded in the condensed consolidated statements of operations (in thousands): Three Months Ended 2024 2023 Hardware revenue $ 10,629 $ 52,732 Services and other revenue 14,840 14,673 Total revenue $ 25,469 $ 67,405 The following table summarizes reportable revenue by geographic regions determined based on the location of the customers (in thousands): Three Months Ended 2024 2023 United States $ 24,294 $ 65,330 Rest of the world 1,175 2,075 Total revenue $ 25,469 $ 67,405
Schedule of Remaining Performance Obligations	As of March 31, 2024 and March 31, 2023, the Company had $440.6 million and $541.1 million of remaining performance obligations, respectively, and the approximate percentages expected to be recognized as revenue in the future are as follows (in thousands, except percentages): March 31, 2024 Total Remaining Percent Expected to be Recognized as Revenue Less Than Two to Greater Than Services and other revenue $ 344,555 15 % 47 % 38 % Hardware revenue 96,013 96 % 4 % — % Total revenue $ 440,568 March 31, 2023 Total Remaining Percent Expected to be Recognized as Revenue Less Than Two to Greater Than Services and other revenue $ 327,149 14 % 48 % 38 % Hardware revenue 213,993 100 % — % — % Total revenue $ 541,142
Schedule of Contract Balances	The following table presents the changes in the deferred revenue balance during the three months ended March 31, 2024 and March 31, 2023 (in thousands): Three Months Ended March 31, 2024 2023 Beginning balance $ 142,647 $ 138,074 Upfront payments received from customers 17,373 30,700 Upfront or annual incentive payments received 497 1,275 Revenue recognized related to amounts that were included in beginning balance of deferred revenue (10,074) (8,463) Revenue recognized related to deferred revenue generated during the period (5,081) (13,591) Ending balance $ 145,362 $ 147,995

SHORT-TERM INVESTMENTS (Tables)

SHORT-TERM INVESTMENTS (Tables)	3 Months Ended
	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Schedule of Short-Term Investments	The Company did not have short-term investments as of March 31, 2024. The following tables summarize the estimated fair value of the Company’s short-term investments and the gross unrealized holding gains and losses as of December 31, 2023 (in thousands). As of December 31, 2023 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Commercial paper $ 1,978 $ — $ — $ 1,978 U.S. government bonds 2,744 — (3) 2,741 Agency bonds 3,503 — (3) 3,500 Total short-term investments $ 8,225 $ — $ (6) $ 8,219

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Schedule of Financial Instruments Measured at Fair Value	The following table provides the financial instruments measured at fair value (in thousands): March 31, 2024 Level 1 Level 2 Level 3 Fair Value Assets: Cash equivalents: Money market fund $ 60,378 $ — $ — $ 60,378 Total financial assets $ 60,378 $ — $ — $ 60,378 Liabilities: Derivative liability $ — $ — $ 7,731 $ 7,731 December 31, 2023 Level 1 Level 2 Level 3 Fair Value Assets: Cash equivalents: Money market fund $ 47,297 $ — $ — $ 47,297 Commercial paper — 3,971 — 3,971 Debt securities: Commercial paper — 1,978 — 1,978 U.S. government bonds — 2,741 — 2,741 Other — 3,500 — 3,500 Total financial assets $ 47,297 $ 12,190 $ — $ 59,487 Liabilities: Derivative liability $ — $ — $ 7,731 $ 7,731

GOODWILL AND INTANGIBLE ASSET_2

GOODWILL AND INTANGIBLE ASSETS, NET (Tables)	3 Months Ended
	Mar. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Goodwill consists of the following (in thousands): March 31, December 31, 2024 2023 Goodwill $ 547,158 $ 547,158 Effect of foreign currency translation 11 47 Total goodwill $ 547,169 $ 547,205
Schedule of Intangible Assets	Intangible assets, net, consists of the following (in thousands): March 31, December 31, 2024 2023 Developed technology $ 32,618 $ 32,618 Trade name 11,300 11,300 Customer relationships 106,800 106,800 Internally developed software 71,738 67,282 Intangible assets 222,456 218,000 Less: Accumulated amortization (67,451) (60,868) Add: Currency translation adjustment 3 14 Total intangible assets, net $ 155,008 $ 157,146

ENERGY STORAGE SYSTEMS, NET (Ta

ENERGY STORAGE SYSTEMS, NET (Tables)	3 Months Ended
	Mar. 31, 2024
Property, Plant and Equipment [Abstract]
Schedule of Energy Storage Systems, Net	Energy storage systems, net, consists of the following (in thousands): March 31, December 31, 2024 2023 Energy storage systems placed into service $ 139,083 $ 141,181 Less: accumulated depreciation (71,800) (70,918) Energy storage systems not yet placed into service 3,951 4,155 Total energy storage systems, net $ 71,234 $ 74,418

CONVERTIBLE NOTES (Tables)

CONVERTIBLE NOTES (Tables)	3 Months Ended
	Mar. 31, 2024
Debt Disclosure [Abstract]
Schedule of Convertible Debt	The outstanding 2028 Convertible Notes balances as of March 31, 2024 and December 31, 2023 are summarized in the following table (in thousands): March 31, 2024 December 31, 2023 Long Term Debt Outstanding principal $ 297,024 $ 297,024 Unamortized 2021 Initial Purchasers’ debt discount and debt issuance cost (6,177) (6,501) Net carrying amount $ 290,847 $ 290,523 The following table presents total interest expense recognized related to the 2028 Convertible Notes during the three months ended March 31, 2024 and 2023 (in thousands) : Three Months Ended 2024 2023 Cash interest expense Contractual interest expense $ 371 $ 575 Non-cash interest expense Amortization of debt discount and debt issuance cost 324 499 Total interest expense $ 695 $ 1,074 The outstanding 2030 Convertible Notes balances as of March 31, 2024 and December 31, 2023 are summarized in the following table (in thousands): March 31, 2024 December 31, 2023 Long Term Debt Outstanding principal $ 240,000 $ 240,000 Unamortized 2023 Initial Purchasers’ debt discount and debt issuance cost (6,647) (6,890) Net carrying amount $ 233,353 $ 233,110 The following table presents total interest expense recognized related to the 2030 Convertible Notes during the three months ended March 31, 2024 (in thousands) : Three Months Ended Cash interest expense Contractual interest expense $ 2,550 Non-cash interest expense Amortization of debt discount and debt issuance cost 243 Total interest expense $ 2,793

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2024
Share-Based Payment Arrangement [Abstract]
Schedule of Activity Under the Plan	The following table summarizes the stock option activity for the period ended March 31, 2024: Number of Weighted- Weighted- Aggregate Balances as of December 31, 2023 9,011,616 $ 6.99 6.0 $ 8,686 Options granted 687,483 3.37 Options forfeited and expired (26,465) 30.26 Balances as of March 31, 2024 9,672,634 $ 6.67 6.0 $ 1,822 Options vested and exercisable — March 31, 2024 7,066,446 $ 5.31 5.1 $ 1,821
Schedule of Restricted Stock Activity	The following table summarizes the RSU activity for the period ended March 31, 2024: Number of RSUs Outstanding (1) Weighted-Average Balances as of December 31, 2023 11,159,272 $ 10.31 RSUs granted 3,378,189 2.76 RSUs vested (5,593,662) 4.32 RSUs forfeited (450,663) 6.53 Balances as of March 31, 2024 8,493,136 $ 11.30 (1) Includes certain restricted stock units with service and market-based vesting criteria.
Schedule of Stock-based Compensation Expense	The following table summarizes stock-based compensation expense recorded in each component of operating expenses in the Company’s condensed consolidated statements of operations and comprehensive loss (in thousands): Three Months Ended 2024 2023 Sales and marketing $ 1,114 $ 945 Research and development 1,531 1,718 General and administrative 5,729 4,539 Total stock-based compensation expense $ 8,374 $ 7,202

NET LOSS PER SHARE (Tables)

NET LOSS PER SHARE (Tables)	3 Months Ended
	Mar. 31, 2024
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Net Loss Per Share	The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders (in thousands, except share and per share amounts): Three Months Ended 2024 2023 Numerator: Net loss attributable to common stockholders $ (72,307) $ (44,778) Denominator: Weighted-average number of shares outstanding used to compute net loss per share attributable to common stockholders, basic and diluted 158,180,137 154,966,163 Net loss per share attributable to common stockholders, basic and diluted $ (0.46) $ (0.29)
Schedule of Potentially Dilutive Shares	The following table shows total outstanding potentially dilutive shares excluded from the computation of diluted net loss per share attributable to common stockholders as their effect would have been anti-dilutive, as of March 31, 2024 and 2023: March 31, 2024 March 31, 2023 Outstanding 2028 Convertible Notes (if converted) 10,157,181 15,730,390 Outstanding 2030 Convertible Notes (if converted) 33,673,584 — Outstanding stock options 9,672,634 9,314,976 Outstanding warrants 2,533 2,533 Outstanding RSUs 8,493,136 7,204,114 Total 61,999,068 32,252,013

INCOME TAXES (Tables)

INCOME TAXES (Tables)	3 Months Ended
	Mar. 31, 2024
Income Tax Disclosure [Abstract]
Schedule of (Provision for) Benefit from Income Taxes and Effective Tax Rates	The following table reflects the Company’s (provision for) benefit from income taxes and the effective tax rates for the periods presented below (in thousands, except effective tax rate): Three Months Ended March 31, 2024 2023 Loss before (provision for) benefit from income taxes $ (72,154) $ (44,869) (Provision for) benefit from income taxes $ (153) $ 91 Effective tax rate (0.2) % 0.2 %

BUSINESS (Details)

BUSINESS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash and cash equivalents	$ 112,804	$ 117,883	$ 105,375
Accumulated deficit	844,801		772,494
Accounts receivable, net of allowances	239,934		$ 302,848
Working capital	168,900
Net loss	(72,307)	(44,778)
Negative cash flows from operating activities	$ (621)	$ (35,821)

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Variable Interest Entities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Assets
Cash and cash equivalents	$ 112,804	$ 105,375	$ 117,883
Other current assets	8,221	9,303
Other noncurrent assets	83,966	81,869
Total assets	1,284,895	1,356,977
Liabilities
Other current liabilities	12,855	12,726
Total liabilities	912,844	930,296
Variable Interest Entity, Primary Beneficiary
Assets
Cash and cash equivalents	791	2,191
Other current assets	22	30
Other noncurrent assets	8,469	8,424
Total assets	9,282	10,645
Liabilities
Accounts payable	2,107	1,405
Other current liabilities	197	1,892
Total liabilities	$ 2,304	$ 3,297

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) segment	Mar. 31, 2023 USD ($)
Concentration Risk [Line Items]
Number of operating segments | segment	1
Variable Interest Entity, Primary Beneficiary
Concentration Risk [Line Items]
Contribution paid	$ 0	$ 0.1
Net loss attributable to Stem	$ 0	$ 0

SUMMARY OF SIGNIFICANT ACCOUN_6

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Significant Customers (Details) - Customer Concentration Risk	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Customer A | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk, percentage	50%		41%
Customer A | Revenue
Concentration Risk [Line Items]
Concentration risk, percentage	24%
Customer B | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk, percentage	17%		28%
Customer B | Revenue
Concentration Risk [Line Items]
Concentration risk, percentage		61%
Customer C | Revenue
Concentration Risk [Line Items]
Concentration risk, percentage	22%
Customer D | Revenue
Concentration Risk [Line Items]
Concentration risk, percentage	22%

REVENUE - Schedule of Disaggreg

REVENUE - Schedule of Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Revenue	$ 25,469	$ 67,405
United States
Disaggregation of Revenue [Line Items]
Revenue	24,294	65,330
Rest of the world
Disaggregation of Revenue [Line Items]
Revenue	1,175	2,075
Hardware revenue
Disaggregation of Revenue [Line Items]
Revenue	10,629	52,732
Services and other revenue
Disaggregation of Revenue [Line Items]
Revenue	$ 14,840	$ 14,673

REVENUE - Narrative (Details)

REVENUE - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Capitalized Contract Cost [Line Items]
Total Remaining Performance Obligations	$ 440,568	$ 541,142
Net book value of the billed and unbilled receivable	108,100
Hardware revenue
Capitalized Contract Cost [Line Items]
Total Remaining Performance Obligations	96,013	$ 213,993
Revenue reduction	$ 33,100

REVENUE - Schedule of Remaining

REVENUE - Schedule of Remaining Performance Obligations (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Remaining Performance Obligations	$ 440,568	$ 541,142
Services and other revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Remaining Performance Obligations	344,555	327,149
Hardware revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Remaining Performance Obligations	$ 96,013	$ 213,993
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-04-01 | Services and other revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue		14%
Percent Expected to be Recognized as Revenue		9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-04-01 | Hardware revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue		100%
Percent Expected to be Recognized as Revenue		9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 | Services and other revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue		48%
Percent Expected to be Recognized as Revenue		4 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 | Hardware revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue		0%
Percent Expected to be Recognized as Revenue		4 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-04-01 | Services and other revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue	15%
Percent Expected to be Recognized as Revenue	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-04-01 | Hardware revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue	96%
Percent Expected to be Recognized as Revenue	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | Services and other revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue	47%
Percent Expected to be Recognized as Revenue	4 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | Hardware revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue	4%
Percent Expected to be Recognized as Revenue	4 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 | Services and other revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue		38%
Percent Expected to be Recognized as Revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 | Hardware revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue		0%
Percent Expected to be Recognized as Revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 | Services and other revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue	38%
Percent Expected to be Recognized as Revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 | Hardware revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percent Expected to be Recognized as Revenue	0%
Percent Expected to be Recognized as Revenue

REVENUE - Schedule of Contract

REVENUE - Schedule of Contract Balances (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Contract With Customer, Liability [Roll Forward]
Beginning balance	$ 142,647	$ 138,074
Upfront payments received from customers	17,373	30,700
Upfront or annual incentive payments received	497	1,275
Revenue recognized related to amounts that were included in beginning balance of deferred revenue	(10,074)	(8,463)
Revenue recognized related to deferred revenue generated during the period	(5,081)	(13,591)
Ending balance	$ 145,362	$ 147,995

SHORT-TERM INVESTMENTS - Schedu

SHORT-TERM INVESTMENTS - Schedule of Short-Term Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Marketable Securities [Line Items]
Amortized Cost		$ 8,225
Unrealized Gain		0
Unrealized Loss		(6)
Estimated Fair Value	$ 0	8,219
Commercial paper
Marketable Securities [Line Items]
Amortized Cost		1,978
Unrealized Gain		0
Unrealized Loss		0
Estimated Fair Value		1,978
U.S. government bonds
Marketable Securities [Line Items]
Amortized Cost		2,744
Unrealized Gain		0
Unrealized Loss		(3)
Estimated Fair Value		2,741
Agency bonds
Marketable Securities [Line Items]
Amortized Cost		3,503
Unrealized Gain		0
Unrealized Loss		(3)
Estimated Fair Value		$ 3,500

SHORT-TERM INVESTMENTS - Additi

SHORT-TERM INVESTMENTS - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($)
Investments, Debt and Equity Securities [Abstract]
Allowance for credit losses recorded	$ 0

FAIR VALUE MEASUREMENTS - Sched

FAIR VALUE MEASUREMENTS - Schedule of Financial Instruments Measured at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt securities:
Available-for-sale	$ 0	$ 8,219
Commercial paper
Debt securities:
Available-for-sale		1,978
U.S. government bonds
Debt securities:
Available-for-sale		2,741
Fair Value, Recurring
Debt securities:
Total financial assets	60,378	59,487
Liabilities:
Derivative liability	7,731	7,731
Fair Value, Recurring | Commercial paper
Debt securities:
Available-for-sale		1,978
Fair Value, Recurring | U.S. government bonds
Debt securities:
Available-for-sale		2,741
Fair Value, Recurring | Other
Debt securities:
Available-for-sale		3,500
Fair Value, Recurring | Money market fund
Cash equivalents:
Cash equivalents	60,378	47,297
Fair Value, Recurring | Commercial paper
Cash equivalents:
Cash equivalents		3,971
Level 1 | Fair Value, Recurring
Debt securities:
Total financial assets	60,378	47,297
Liabilities:
Derivative liability	0	0
Level 1 | Fair Value, Recurring | Commercial paper
Debt securities:
Available-for-sale		0
Level 1 | Fair Value, Recurring | U.S. government bonds
Debt securities:
Available-for-sale		0
Level 1 | Fair Value, Recurring | Other
Debt securities:
Available-for-sale		0
Level 1 | Fair Value, Recurring | Money market fund
Cash equivalents:
Cash equivalents	60,378	47,297
Level 1 | Fair Value, Recurring | Commercial paper
Cash equivalents:
Cash equivalents		0
Level 2 | Fair Value, Recurring
Debt securities:
Total financial assets	0	12,190
Liabilities:
Derivative liability	0	0
Level 2 | Fair Value, Recurring | Commercial paper
Debt securities:
Available-for-sale		1,978
Level 2 | Fair Value, Recurring | U.S. government bonds
Debt securities:
Available-for-sale		2,741
Level 2 | Fair Value, Recurring | Other
Debt securities:
Available-for-sale		3,500
Level 2 | Fair Value, Recurring | Money market fund
Cash equivalents:
Cash equivalents	0	0
Level 2 | Fair Value, Recurring | Commercial paper
Cash equivalents:
Cash equivalents		3,971
Level 3 | Fair Value, Recurring
Debt securities:
Total financial assets	0	0
Liabilities:
Derivative liability	7,731	7,731
Level 3 | Fair Value, Recurring | Commercial paper
Debt securities:
Available-for-sale		0
Level 3 | Fair Value, Recurring | U.S. government bonds
Debt securities:
Available-for-sale		0
Level 3 | Fair Value, Recurring | Other
Debt securities:
Available-for-sale		0
Level 3 | Fair Value, Recurring | Money market fund
Cash equivalents:
Cash equivalents	$ 0	0
Level 3 | Fair Value, Recurring | Commercial paper
Cash equivalents:
Cash equivalents		$ 0

FAIR VALUE MEASUREMENTS - Narra

FAIR VALUE MEASUREMENTS - Narrative (Details) - Convertible Notes - Level 2 - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
2028 Convertible Notes
Debt Instrument [Line Items]
Convertible debt	$ 144.1	$ 149.1
2030 Convertible Notes
Debt Instrument [Line Items]
Convertible debt	$ 125.7	$ 175.8

GOODWILL AND INTANGIBLE ASSET_3

GOODWILL AND INTANGIBLE ASSETS, NET - Schedule of Goodwill Consists (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 547,158	$ 547,158
Effect of foreign currency translation	11	47
Total goodwill	$ 547,169	$ 547,205

GOODWILL AND INTANGIBLE ASSET_4

GOODWILL AND INTANGIBLE ASSETS, NET - Schedule of Intangible Assets, Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 222,456		$ 218,000
Less: Accumulated amortization	(67,451)		(60,868)
Add: Currency translation adjustment	3		14
Total intangible assets, net	155,008		157,146
Amortization of intangible assets	6,600	$ 6,500
Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	32,618		32,618
Trade name
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	11,300		11,300
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	106,800		106,800
Internally developed software
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 71,738		$ 67,282

ENERGY STORAGE SYSTEMS, NET - S

ENERGY STORAGE SYSTEMS, NET - Schedule of Energy Storage Systems, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Less: accumulated depreciation	$ (71,800)	$ (70,918)
Total energy storage systems, net	71,234	74,418
Energy storage systems placed into service
Property, Plant and Equipment [Line Items]
Total energy storage systems, gross	139,083	141,181
Energy storage systems not yet placed into service
Property, Plant and Equipment [Line Items]
Total energy storage systems, gross	$ 3,951	$ 4,155

ENERGY STORAGE SYSTEMS, NET - N

ENERGY STORAGE SYSTEMS, NET - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 3,000	$ 3,600
Impairment loss of energy storage systems	$ 0	$ 851

CONVERTIBLE NOTES - Narrative (

CONVERTIBLE NOTES - Narrative (Details) $ / shares in Units, $ in Millions				3 Months Ended	12 Months Ended
	Apr. 03, 2023 USD ($) day $ / shares	Nov. 22, 2021 USD ($) day $ / shares	Nov. 19, 2021 USD ($) $ / shares	Jun. 30, 2023 USD ($)	Dec. 31, 2021 USD ($)	Mar. 29, 2023 $ / shares
Capped Call Options
Debt Instrument [Line Items]
Cost of capped calls			$ 66.7	$ 27.8	$ 66.7
Initial strike price (in dollars per share) | $ / shares			$ 29.2428			$ 7.1272
Cap price (in dollars per share) | $ / shares			$ 49.6575			$ 11.1800
2028 Convertible Notes | Convertible Notes
Debt Instrument [Line Items]
Face amount		$ 460
Fixed interest rate, annual		0.50%
Conversion ratio		0.0341965
Conversion price (in dollars per share) | $ / shares		$ 29.24
Redemption price, percentage		100%
Proceeds from convertible notes		$ 445.7		99.8
Cancellation of aggregate principal				163
Gain on extinguishment of debt, net				$ 59.4
Effective interest percentage		0.90%
Term		7 years
2028 Convertible Notes | Convertible Notes | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Conversion price, percentage		130%
2028 Convertible Notes | Convertible Notes | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Threshold trading days | day		20
2030 Convertible Notes | Convertible Notes
Debt Instrument [Line Items]
Face amount	$ 240
Fixed interest rate, annual	4.25%
Conversion ratio	0.1403066
Conversion price (in dollars per share) | $ / shares	$ 7.1272
Redemption price, percentage	100%
Proceeds from convertible notes	$ 232.4
Effective interest percentage	4.70%
Term	7 years
Debt issuance costs	$ 7.6
2030 Convertible Notes | Convertible Notes | Capped Call Options
Debt Instrument [Line Items]
Proceeds from convertible notes	$ 27.8
2030 Convertible Notes | Convertible Notes | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Conversion price, percentage	130%
2030 Convertible Notes | Convertible Notes | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Threshold trading days | day	20

CONVERTIBLE NOTES - Schedule of

CONVERTIBLE NOTES - Schedule of Outstanding Convertible Notes (Details) - Convertible Notes - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
2028 Convertible Notes
Debt Instrument [Line Items]
Outstanding principal	$ 297,024	$ 297,024
Unamortized 2021 Initial Purchasers’ debt discount and debt issuance cost	(6,177)	(6,501)
Long-Term Debt, Total	290,847	290,523
2030 Convertible Notes
Debt Instrument [Line Items]
Outstanding principal	240,000	240,000
Unamortized 2021 Initial Purchasers’ debt discount and debt issuance cost	(6,647)	(6,890)
Long-Term Debt, Total	$ 233,353	$ 233,110

CONVERTIBLE NOTES - Schedule _2

CONVERTIBLE NOTES - Schedule of Interest Expense Recognized Related to Convertible Note (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Debt Instrument [Line Items]
Amortization of debt discount and debt issuance cost	$ 422	$ 386
2028 Convertible Notes | Convertible Notes
Debt Instrument [Line Items]
Contractual interest expense	371	575
Amortization of debt discount and debt issuance cost	324	499
Total interest expense	695	$ 1,074
2030 Convertible Notes | Convertible Notes
Debt Instrument [Line Items]
Contractual interest expense	2,550
Amortization of debt discount and debt issuance cost	243
Total interest expense	$ 2,793

STOCK-BASED COMPENSATION - Sche

STOCK-BASED COMPENSATION - Schedule of Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Number of Options Outstanding
Options outstanding, beginning of period (in shares)	9,011,616
Options granted (in shares)	687,483
Options forfeited (in shares)	(26,465)
Options outstanding, end of period (in shares)	9,672,634	9,011,616
Options vested and exercisable (in shares)	7,066,446
Weighted- Average Exercise Price Per Share
Options outstanding, weighted average exercise price (in dollars per share)	$ 6.67	$ 6.99
Options granted, weighted average exercise price (in dollars per share)	3.37
Options forfeited, weighted average exercise price (in dollars per share)	30.26
Options vested and exercisable, weighted-average exercise price (in dollars per share)	$ 5.31
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average remaining contractual life, options outstanding	6 years	6 years
Weighted average remaining contractual life, options vested and exercisable	5 years 1 month 6 days
Aggregate intrinsic value, options outstanding	$ 1,822	$ 8,686
Aggregate intrinsic value, options vested and exercisable	$ 1,821

STOCK-BASED COMPENSATION - Narr

STOCK-BASED COMPENSATION - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining unrecognized stock-based compensation expense	$ 14,200
Total stock-based compensation expense	8,374	$ 7,202
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1,531	1,718
Internally developed software | Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1,000	$ 900
RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining unrecognized stock-based compensation expense	$ 60,400
Weighted average period for recognition of stock-based compensation expense	1 year 9 months 18 days
Outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period for recognition of stock-based compensation expense	1 year 4 months 24 days

STOCK-BASED COMPENSATION - Sc_2

STOCK-BASED COMPENSATION - Schedule of RSU Activity (Details) - RSU	3 Months Ended
	Mar. 31, 2024 $ / shares shares
Number of RSUs Outstanding
RSUs outstanding, beginning (in shares) | shares	11,159,272
RSUs granted (in shares) | shares	3,378,189
RSUs vested (in shares) | shares	(5,593,662)
RSUs forfeited (in shares) | shares	(450,663)
RSUs outstanding, ending (in shares) | shares	8,493,136
Weighted-Average Grant Date Fair Value Per Share
RSUs outstanding, weighted average grant date fair value, beginning (in dollars per share) | $ / shares	$ 10.31
RSUs granted, weighted average grant date fair value (in dollars per share) | $ / shares	2.76
RSUs vested, weighted average grant date fair value (in dollars per share) | $ / shares	4.32
RSUs forfeited, weighted average grant date fair value (in dollars per share) | $ / shares	6.53
RSUs outstanding, weighted average grant date fair value, ending (in dollars per share) | $ / shares	$ 11.30

STOCK-BASED COMPENSATION - Sc_3

STOCK-BASED COMPENSATION - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 8,374	$ 7,202
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1,114	945
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1,531	1,718
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 5,729	$ 4,539

NET LOSS PER SHARE - Schedule o

NET LOSS PER SHARE - Schedule of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Numerator:
Net loss per share attributable to common stockholders, basic	$ (72,307)	$ (44,778)
Net loss per share attributable to common stockholders, diluted	$ (72,307)	$ (44,778)
Denominator:
Weighted-average number of shares outstanding used to compute net loss per share attributable to common stockholders, basic (in shares)	158,180,137	154,966,163
Weighted-average number of shares outstanding used to compute net loss per share attributable to common stockholders, diluted (in shares)	158,180,137	154,966,163
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.46)	$ (0.29)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.46)	$ (0.29)

NET LOSS PER SHARE - Schedule_2

NET LOSS PER SHARE - Schedule of Antidilutive Securities (Details) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive shares (in shares)	61,999,068	32,252,013
Outstanding 2028 Convertible Notes (if converted)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive shares (in shares)	10,157,181	15,730,390
Outstanding 2030 Convertible Notes (if converted)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive shares (in shares)	33,673,584	0
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive shares (in shares)	9,672,634	9,314,976
Outstanding warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive shares (in shares)	2,533	2,533
Outstanding RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive shares (in shares)	8,493,136	7,204,114

INCOME TAXES - Schedule of Prov

INCOME TAXES - Schedule of Provision (Benefit) for Income Taxes and the Effective Tax Rates (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Loss before (provision for) benefit from income taxes	$ (72,154)	$ (44,869)
(Provision for) benefit from income taxes	$ (153)	$ 91
Effective tax rate	(0.20%)	0.20%

INCOME TAXES - Narrative (Detai

INCOME TAXES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Tax provision (benefit)	$ 153	$ (91)
Effective tax rate	(0.20%)	0.20%
(Benefit) for income taxes, federal	$ 300

COMMITMENTS AND CONTINGNECIES (

COMMITMENTS AND CONTINGNECIES (Details) $ in Millions	Mar. 31, 2024 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Loss contingency accrual amount	$ 5.6