Nv Energy (NVE) 8-K NV Energy, Inc., Reports Second Quarter Earnings

Exhibit 99.1

FOR IMMEDIATE RELEASE
August 2, 2010	Analyst Contact: Britta Carlson, (702) 402-5624
	Media Contact: Karl Walquist, (775) 834-3891

NV Energy, Inc., Reports Second Quarter Earnings

Las Vegas — NV Energy, Inc. (NYSE: NVE) today announced consolidated net income of $36.9 million, or 16 cents per share, for the quarter ended June 30, 2010, compared with consolidated net income of $18.4 million, or 8 cents per share, for the same period in 2009.

For the first six-months, NV Energy earned $35.2 million or 15 cents per share in 2010 compared with a net loss of $3.9 million or 2 cents per share for the same period in 2009.

“We are very pleased with the results we achieved in this year’s second quarter,” Michael Yackira, president and chief executive officer of NV Energy, said. “While the increase was largely a result of higher income associated with investment in generating facilities, it was also due to cost discipline throughout the company.”

Webcast Scheduled for 7 a.m. PDT today, Monday, August 2, 2010

Senior management of NV Energy will review the company’s 2010 second quarter financial results and other matters during a conference call and live webcast today, Monday, August 2, at 7 a.m. Pacific Daylight Time.

The webcast will be accessible on the NV Energy website:

www.nvenergy.com.

An archived version of the webcast will remain on the NV Energy website for approximately one month following the live webcast. To listen to a recording of the call by telephone, call (800) 475-6701, and international callers should dial (320) 365-3844. Use the conference call access code, 163910, to listen to the recording.

Headquartered in Las Vegas, NV Energy, Inc. is a holding company whose principal subsidiaries, Nevada Power Company and Sierra Pacific Power Company, are doing business as NV Energy. Serving a 54,500-square-mile service territory that stretches north to south from Elko to Laughlin, NV Energy provides a wide range of energy services and products to approximately 2.4 million citizens of Nevada as well as approximately 40 million tourists annually.

This press release may contain forward-looking statements regarding the future performance of NV Energy, Inc. and its subsidiaries, Nevada Power Company and Sierra Pacific Power Company both d/b/a NV Energy, within the meaning of the Private Securities Litigation Reform Act of 1995. These statements are subject to a variety of risks and uncertainties that could cause actual results to differ materially from current expectations. These risks and uncertainties

P.O. BOX 98910, LAS VEGAS, NEVADA 89151-0001     6226 WEST SAHARA AVENUE, LAS VEGAS, NEVADA 89146
P.O. BOX 30150, RENO, NEVADA 89520-3150     6100 NEIL ROAD, RENO, NEVADA 89511 nvenergy.com

include, but are not limited to, NV Energy Inc.’s ability to maintain access to the capital markets, NV Energy Inc.’s ability to receive dividends from its subsidiaries, the financial performance of NV Energy Inc.’s subsidiaries, particularly Nevada Power Company and Sierra Pacific Power Company both d/b/a NV Energy, and the discretion of NV Energy Inc.’s Board of Directors with respect to the payment of future dividends based on its periodic review of factors that ordinarily affect dividend policy, such as current and prospective financial condition, earnings and liquidity, prospective business conditions, regulatory factors, and dividend restrictions in NV Energy Inc.’s and its subsidiaries’ financing agreements. For Nevada Power Company and Sierra Pacific Power Company both d/b/a NV Energy, these risks and uncertainties include, but are not limited to, future economic conditions both nationally and regionally, changes in the rate of industrial, commercial and residential growth in their service territories, their ability to procure sufficient renewable energy sources in each compliance year to satisfy the Nevada Renewable Energy Portfolio Standard, changes in environmental laws and regulations, construction risks, their ability to maintain access to the capital markets for general corporate purposes and to finance construction projects, employee workforce factors, including changes in and renewals of collective bargaining agreements, strikes or work stoppages, unseasonable weather, drought, threat of wildfire and other natural phenomena, their ability to purchase sufficient fuel, natural gas and power to meet their power demands and natural gas demands for Sierra Pacific Power Company d/b/a NV Energy, financial and wholesale market conditions, and unfavorable rulings in their pending and future regulatory filings. Additional cautionary statements regarding other risk factors that could have an effect on the future performance of NV Energy, Inc., Nevada Power Company and Sierra Pacific Power Company both d/b/a NV Energy are contained in their quarterly reports on Form 10-Q for the quarter ended March 31, 2010, and their Annual Reports on Form 10-K as amended by Form 10-K/A for the year ended December 31, 2009, each filed with the SEC. NV Energy Inc., Nevada Power Company and Sierra Pacific Power Company both d/b/a NV Energy undertake no obligation to release publicly the result of any revisions to these forward-looking statements that may be made to reflect events or circumstances after the date hereof or to reflect the occurrence of unanticipated events.

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NV ENERGY, INC.
CONSOLIDATED STATEMENTS OF OPERATIONS
(Dollars in Thousands, Except Per Share Amounts)
(unaudited)

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2010			2009			2010			2009
OPERATING REVENUES	$	785,361		$	838,641		$	1,502,330		$	1,593,908
OPERATING EXPENSES:
Fuel for power generation		181,662			204,285			403,281			434,389
Purchased power		165,321			194,970			272,684			320,357
Gas purchased for resale		25,154			19,916			90,713			90,188
Deferred energy		54,933			93,577			72,499			139,212
Other operating expenses		104,066			109,886			213,172			224,563
Maintenance		28,860			27,632			54,589			62,032
Depreciation and amortization		84,696			80,323			165,644			158,371
Taxes other than income		15,939			13,753			32,112			28,400
Total Operating Expenses		660,631			744,342			1,304,694			1,457,512
OPERATING INCOME		124,730			94,299			197,636			136,396
OTHER INCOME (EXPENSE):
Interest expense (net of AFUDC-debt: $5,926, $7,022, $10,864 and $12,168)		(80,772	)		(83,559	)		(160,836	)		(166,192	)
Interest income (expense) on regulatory items		(2,997	)		(254	)		(5,068	)		926
AFUDC-equity		7,138			8,548			13,091			14,766
Other income		15,401			18,402			21,278			23,460
Other expense		(9,659	)		(9,460	)		(12,725	)		(15,038	)
Total Other Income (Expense)		(70,889	)		(66,323	)		(144,260	)		(142,078	)
Income (Loss) Before Income Tax Expense		53,841			27,976			53,376			(5,682	)
Income tax expense (benefit)		16,895			9,593			18,151			(1,821	)
NET INCOME (LOSS)	$	36,946		$	18,383		$	35,225		$	(3,861	)
Amount per share basic and diluted — (Note 9)
Net income (loss) per share basic and diluted	$	0.16		$	0.08		$	0.15		$	(0.02	)
Weighted Average Shares of Common Stock Outstanding — basic		234,995,083			234,474,727			234,927,239			234,403,282
Weighted Average Shares of Common Stock Outstanding — diluted		236,134,449			235,089,193			235,965,452			234,403,282
Dividends Declared Per Share of Common Stock	$	0.11		$	0.10		$	0.22		$	0.20

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NEVADA POWER COMPANY
CONSOLIDATED STATEMENTS OF OPERATIONS
(Dollars in Thousands)
(unaudited)

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2010			2009			2010			2009
OPERATING REVENUES	$	540,799		$	575,769		$	967,759		$	1,012,298
OPERATING EXPENSES:
Fuel for power generation		132,067			140,333			288,182			294,395
Purchased power		124,740			165,292			195,967			253,498
Deferred energy		39,960			59,809			59,423			97,999
Other operating expenses		64,696			68,057			132,576			138,250
Maintenance		18,219			18,732			35,238			46,266
Depreciation and amortization		57,654			53,510			112,755			105,873
Taxes other than income		9,793			8,361			19,819			17,424
Total Operating Expenses		447,129			514,094			843,960			953,705
OPERATING INCOME (LOSS)		93,670			61,675			123,799			58,593
OTHER INCOME (EXPENSE):
Interest expense (net of AFUDC-debt: $5,444, $6,106, $9,976 and $10,668)		(53,996	)		(57,137	)		(107,352	)		(112,180	)
Interest income (expense) on regulatory items		(777	)		790			(808	)		2,643
AFUDC-equity		6,398			7,552			11,760			13,173
Other income		2,659			12,608			5,242			14,950
Other expense		(5,172	)		(7,591	)		(6,304	)		(10,798	)
Total Other Income (Expense)		(50,888	)		(43,778	)		(97,462	)		(92,212	)
Income (Loss) Before Income Tax Expense		42,782			17,897			26,337			(33,619	)
Income tax expense (benefit)		12,998			5,396			8,879			(10,969	)
NET INCOME (LOSS)	$	29,784		$	12,501		$	17,458		$	(22,650	)

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SIERRA PACIFIC POWER COMPANY
CONSOLIDATED INCOME STATEMENTS
(Dollars in Thousands)
(unaudited)

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2010			2009			2010			2009
OPERATING REVENUES:
Electric	$	204,151		$	230,914		$	414,132		$	468,652
Gas		40,405			31,948			120,425			112,941
Total Operating Revenues		244,556			262,862			534,557			581,593
OPERATING EXPENSES:
Fuel for power generation		49,595			63,952			115,099			139,994
Purchased power		40,581			29,678			76,717			66,859
Gas purchased for resale		25,154			19,916			90,713			90,188
Deferral of energy — electric		8,725			29,780			7,225			41,576
Deferral of energy — gas		6,248			3,988			5,851			(363	)
Other operating expenses		38,288			40,890			78,960			84,905
Maintenance		10,641			8,900			19,351			15,766
Depreciation and amortization		27,042			26,813			52,889			52,498
Taxes other than income		6,098			5,360			12,164			10,884
Total Operating Expenses		212,372			229,277			458,969			502,307
OPERATING INCOME		32,184			33,585			75,588			79,286
OTHER INCOME (EXPENSE):
Interest expense (net of AFUDC-debt: $482, $916, $888 and $1,500)		(17,113	)		(16,759	)		(34,158	)		(34,686	)
Interest income (expense) on regulatory items		(2,220	)		(1,044	)		(4,260	)		(1,717	)
AFUDC-equity		740			996			1,331			1,593
Other income		10,142			5,792			11,897			8,507
Other expense		(4,401	)		(1,797	)		(6,270	)		(3,788	)
Total Other Income (Expense)		(12,852	)		(12,812	)		(31,460	)		(30,091	)
Income Before Income Tax Expense		19,332			20,773			44,128			49,195
Income tax expense		8,017			5,969			15,693			15,255
NET INCOME	$	11,315		$	14,804		$	28,435		$	33,940

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Gross margin is presented by Nevada Power Company and Sierra Pacific Power Company both d/b/a NV Energy in order to provide information by segment that management believes aids the reader in determining how profitable the electric and gas business is at the most fundamental level. Gross margin, which is a “non-GAAP financial measure” as defined in accordance with SEC rules, provides a measure of income available to support the other operating expenses of the business and is utilized by management in its analysis of its business.

Nevada Power Company and Sierra Pacific Power Company both d/b/a NV Energy believe presenting gross margin allows the reader to assess the impact of regulatory treatment and their overall regulatory environment on a consistent basis. Gross margin, as a percentage of revenue, is primarily impacted by the fluctuations in regulated electric and natural gas supply costs versus the fixed rates collected from customers. While these fluctuating costs impact gross margin as a percentage of revenue, they only impact gross margin amounts if the costs cannot be passed through to customers. Gross margin, which Nevada Power Company and Sierra Pacific Power Company both d/b/a NV Energy calculate as operating revenues less energy costs, provides a measure of income available to support the other operating expenses. Gross margin changes based on such factors as general base rate adjustments (which are required to be filed by statute every three years) and reflect Nevada Power Company and Sierra Pacific Power Company’s both d/b/a NV Energy strategy to increase internal power generation versus purchased power, which generates no gross margin. Reconciliations between GAAP operating revenues and gross margin are provided in tables herein. These non-GAAP measures should not be considered as substitutes for the GAAP measures.

RECONCILIATION OF NON-GAAP FINANCIAL MEASURES
Gross Margin
(Dollars in Thousands)
(Unaudited)

Nevada Power Company

	Three Months Ended June 30,							Six Months Ended June 30,
					Change							Change
					from							from
					Prior							Prior
	2010		2009		Year %			2010		2009		Year %
Operating Revenues	$	540,799	$	575,769		-6.1	%	$	967,759	$	1,012,298		-4.4	%
Energy Costs:
Fuel for power generation		132,067		140,333					288,182		294,395
Purchased power		124,740		165,292					195,967		253,498
Deferred energy		39,960		59,809					59,423		97,999
	$	296,767	$	365,434		-18.8	%	$	543,572	$	645,892		-15.8	%
Gross Margin	$	244,032	$	210,335		16.0	%	$	424,187	$	366,406		15.8	%
Other operating expenses		64,696		68,057					132,576		138,250
Maintenance		18,219		18,732					35,238		46,266
Depreciation and amortization		57,654		53,510					112,755		105,873
Taxes other than income		9,793		8,361					19,819		17,424
Operating Income	$	93,670	$	61,675		-51.9	%	$	123,799	$	58,593		-111.3	%

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Sierra Pacific Power Company

	Three Months Ended June 30,							Six Months Ended June 30,
					Change								Change
					from								from
					Prior								Prior
	2010		2009		Year %			2010		2009			Year %
Operating Revenues:
Electric	$	204,151	$	230,914				$	414,132	$	468,652
Gas		40,405		31,948					120,425		112,941
	$	244,556	$	262,862		-7.0	%	$	534,557	$	581,593			-8.1	%
Energy Costs:
Fuel for power generation		49,595		63,952					115,099		139,994
Purchased power		40,581		29,678					76,717		66,859
Gas purchased for resale		25,154		19,916					90,713		90,188
Deferred energy — electric		8,725		29,780					7,225		41,576
Deferred energy — gas		6,248		3,988					5,851		(363	)
	$	130,303	$	147,314		-11.5	%	$	295,605	$	338,254			-12.6	%
Gross Margin	$	114,253	$	115,548		-1.1	%	$	238,952	$	243,339			-1.8	%
Other operating expenses		38,288		40,890					78,960		84,905
Maintenance		10,641		8,900					19,351		15,766
Depreciation and amortization		27,042		26,813					52,889		52,498
Taxes other than income		6,098		5,360					12,164		10,884
Operating Income	$	32,184	$	33,585		-4.2	%	$	75,588	$	79,286			-4.7	%

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Summary of Selected Operating Statistics

Nevada Power Company
Operating Revenues
(dollars in thousands)

	Three Months Ended June 30,									Six Months Ended June 30,
					Change									Change
					from			Avg.						from
					Prior			Change in						Prior
	2010		2009		Year %			customers		2010		2009		Year %
Operating Revenues:
Residential	$	242,295	$	263,556		-8.1	%		0.2%	$	438,888	$	454,926		-3.5	%
Commercial		113,806		120,297		-5.4	%		0.5%		208,075		217,091		-4.2	%
Industrial		168,747		171,895		-1.8	%		-0.2%		288,395		299,934		-3.8	%
Retail revenues		524,848		555,748		-5.6	%				935,358		971,951		-3.8	%
Other		15,951		20,021		-20.3	%				32,401		40,347		-19.7	%
Total Operating Revenues	$	540,799	$	575,769		-6.1	%			$	967,759	$	1,012,298		-4.4	%
Retail sales in thousands of MWhs		4,960		5,309		-6.6	%				9,047		9,429		-4.1	%

Sierra Pacific Power Company
Operating Revenues
(dollars in thousands)

	Three Months Ended June 30,									Six Months Ended June 30,
					Change									Change
					from			Avg.						from
					Prior			Change in						Prior
	2010		2009		Year %			customers		2010		2009		Year %
Electric Operating Revenues:
Residential	$	70,363	$	75,908		-7.3	%		0.2%	$	153,522	$	169,693		-9.5	%
Commercial		81,643		98,066		-16.7	%		0.3%		158,618		188,504		-15.9	%
Industrial		44,830		49,277		-9.0	%		-1.7%		87,462		95,344		-8.3	%
Retail revenues		196,836		223,251		-11.8	%				399,602		453,541		-11.9	%
Other		7,315		7,663		-4.5	%				14,530		15,111		-3.8	%
Total Revenues	$	204,151	$	230,914		-11.6	%			$	414,132	$	468,652		-11.6	%
Retail sales in thousands of MWhs		1,923		1,942		-1.0	%				3,883		3,922		-1.0	%

	Three Months Ended June 30,									Six Months Ended June 30,
					Change									Change
					from			Avg.						from
					Prior			Change in						Prior
	2010		2009		Year %			customers		2010		2009		Year %
Gas Operating Revenues:
Residential	$	20,382	$	17,788		14.6	%			$	62,745	$	63,670		-1.5	%
Commercial		8,916		8,439		5.7	%				29,397		30,279		-2.9	%
Industrial		3,505		3,733		-6.1	%				9,444		9,625		-1.9	%
Retail revenues		32,803		29,960		9.5	%		0.7%		101,586		103,574		-1.9	%
Wholesale revenue		7,007		1,426		391.4	%				17,569		8,160		115.3	%
Miscellaneous		595		562		5.9	%				1,270		1,207		5.2	%
Total Revenues	$	40,405	$	31,948		26.5	%			$	120,425	$	112,941		6.6	%
Retail sales in thousands of decatherms		2,852		2,260		26.2	%				8,836		8,366		5.6	%

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Financial Highlights
(Dollars in Thousands)
(Unaudited)

NV Energy, Inc

	June 30, 2010				June 30, 2009
Capital Structure
Current maturities of long-term debt	$	357,163	4.1	%	$	9,085	0.1	%
Long-term debt		5,242,442	59.5	%		5,571,799	64.3	%
Total debt	$	5,599,605	63.6	%	$	5,580,884	64.4	%
Total shareholders’ equity		3,210,763	36.4	%		3,083,773	35.6	%
Total capitalization (including current maturities of long-term debt)	$	8,810,368	100.0	%	$	8,664,657	100.0	%

Nevada Power Company

	June 30, 2010				June 30, 2009
Capital Structure
Current maturities of long-term debt	$	357,163	5.5	%	$	9,085	0.1	%
Long-term debt		3,475,347	53.9	%		3,712,016	59.3	%
Total debt	$	3,832,510	59.4	%	$	3,721,101	59.4	%
Total shareholders’ equity		2,614,530	40.6	%		2,542,948	40.6	%
Total capitalization (including current maturities of long-term debt)	$	6,447,040	100.0	%	$	6,264,049	100.0	%

Sierra Pacific Power Company

	June 30, 2010				June 30, 2009
Capital Structure
Current maturities of long-term debt	$	—	0.0	%	$	—	0.0	%
Long-term debt		1,281,500	55.9	%		1,373,992	58.6	%
Total debt	$	1,281,500	55.9	%	$	1,373,992	58.6	%
Total shareholders’ equity		1,012,710	44.1	%		970,218	41.4	%
Total capitalization (including current maturities of long-term debt)	$	2,294,210	100.0	%	$	2,344,210	100.0	%

NVE Available Liquidity as of June 30, 2010 (dollars in millions)	NVE		NPC			SPPC
Cash and Cash Equivalents	$	17.5	$	46.9		$	67.0
Balance available on Revolving Credit Facilities		N/A		310.3			233.9
— Less reduction for hedging obligations		N/A		(65.8	)		(21.4	)
	$	17.5	$	291.4		$	279.5

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