UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2010 I.R.S. Employer Commission File Registrant, Address of Principal Executive Offices and Telephone Identification State of 1-08788 NV ENERGY, INC. 88-0198358 Nevada 6226 West Sahara Avenue Las Vegas, Nevada 89146 (702) 402-5000 2-28348 NEVADA POWER COMPANY d/b/a NV ENERGY 88-0420104 Nevada 6226 West Sahara Avenue Las Vegas, Nevada 89146 (702) 402-5000 0-00508 SIERRA PACIFIC POWER COMPANY d/b/a NV ENERGY 88-0044418 Nevada P.O. Box 10100 (6100 Neil Road) Reno, Nevada 89520-0024 (89511) (775) 834-4011 (Title of each class) (Name of exchange on which registered) Securities registered pursuant to Section 12(b) of the Act: New York Stock Exchange Securities of NV Energy, Inc.: Common Stock, $1.00 par value Securities registered pursuant to Section 12(g) of the Act: Securities of Nevada Power Company: Common Stock, $1.00 stated value Securities of Sierra Pacific Power Company: Common Stock, $3.75 par value Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act: NV Energy, Inc. Yes ፼ No អ Nevada Power Company Yes អ No ፼ Sierra Pacific Power Company Yes អ No ፼ Indicate by check mark if each of the registrants is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes អ No ፼ Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes ፼ No (Response applicable to all registrants). Indicate by check mark whether each of the registrants (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ፼ No អ Indicate by check mark if disclosure of delinquent filers pursuant to item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrants’ knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ፼ Indicate by check mark whether any registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. (See definition of ‘‘large accelerated filer’’, ‘‘accelerated filer’’ and ‘‘smaller reporting company’’ in Rule 12b-2 of the Exchange Act). NV Energy, Inc.: Large accelerated filer ፼ Accelerated filer អ Non-accelerated filer អ Smaller reporting company អ Nevada Power Company: Large accelerated filer អ Accelerated filer អ Non-accelerated filer ፼ Smaller reporting company អ Sierra Pacific Power Company: Large accelerated filer អ Accelerated filer អ Non-accelerated filer ፼ Smaller reporting company អ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes No ፼ (Response applicable to all registrants) State the aggregate market value of NV Energy, Inc.’s common stock held by non-affiliates. As of June 30, 2010: $2,776,606,796 Indicate the number of shares outstanding of each of the issuer’s classes of Common Stock, as of the latest practicable date. Common Stock, $1.00 par value, of NV Energy, Inc. outstanding at February 21, 2011: 235,591,058 Shares NV Energy, Inc. is the sole holder of the 1,000 shares of outstanding Common Stock, $1.00 stated value, of Nevada Power Company. NV Energy, Inc. is the sole holder of the 1,000 shares of outstanding Common Stock, $3.75 par value, of Sierra Pacific Power Company. DOCUMENTS INCORPORATED BY REFERENCE: Portions of NV Energy, Inc.’s definitive proxy statement to be filed in connection with the annual meeting of shareholders, to be held May 3, 2011, are incorporated by reference into Part III hereof. This combined Annual Report on Form 10-K is separately filed by NV Energy, Inc., Nevada Power Company and Sierra Pacific Power Company. Information contained in this document relating to Nevada Power Company is filed by NV Energy, Inc. and separately by Nevada Power Company on its own behalf. Nevada Power Company makes no representation as to information relating to NV Energy, Inc. or its subsidiaries, except as it may relate to Nevada Power Company. Information contained in this document relating to Sierra Pacific Power Company is filed by NV Energy, Inc. and separately by Sierra Pacific Power Company on its own behalf. Sierra Pacific Power Company makes no representation as to information relating to NV Energy, Inc. or its subsidiaries, except as it may relate to Sierra Pacific Power Company. NV ENERGY, INC. NEVADA POWER COMPANY SIERRA PACIFIC POWER COMPANY 2010 ANNUAL REPORT ON FORM 10-K CONTENTS Page ACRONYMS & TERMS ...................................................... 4 PART I ITEM 1. BUSINESS ..................................................... 7 ITEM 1A. RISK FACTORS ................................................. 38 ITEM 1B. UNRESOLVED STAFF COMMENTS ...................................... 46 ITEM 2. PROPERTIES ................................................... 47 ITEM 3. LEGAL PROCEEDINGS ............................................. 48 ITEM 4. [REMOVED AND RESERVED] ......................................... 49 PART II ITEM 5. MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES NVE........................... 49 ITEM 6. SELECTED FINANCIAL DATA ......................................... 51 ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS ................................................... 53 Executive Overview ........................................ 56 NV Energy, Inc. ........................................... 72 RESULTS OF OPERATIONS ................................. 72 ANALYSIS OF CASH FLOWS ................................ 73 LIQUIDITY AND CAPITAL RESOURCES (NVE CONSOLIDATED)........... 73 Nevada Power Company .................................... 81 RESULTS OF OPERATIONS ................................. 81 ANALYSIS OF CASH FLOWS ................................ 88 LIQUIDITY AND CAPITAL RESOURCES .......................... 88 Sierra Pacific Power Company ................................ 96 RESULTS OF OPERATIONS ................................. 96 ANALYSIS OF CASH FLOWS ................................ 104 LIQUIDITY AND CAPITAL RESOURCES .......................... 105 ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK .............. 112 ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA ......................... 114 Report of Independent Registered Public Accounting Firm ............ 115 NV Energy, Inc. ........................................... 118 CONSOLIDATED INCOME STATEMENTS ......................... 118 CONSOLIDATED BALANCE SHEET ............................ 119 CONSOLIDATED STATEMENTS OF CASH FLOWS ................... 121 CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME ........... 122 CONSOLIDATED STATEMENTS OF SHAREHOLDERS’ EQUITY ............ 123 Nevada Power Company .................................... 124 CONSOLIDATED INCOME STATEMENTS ......................... 124 CONSOLIDATED BALANCE SHEET ............................ 125 CONSOLIDATED STATEMENTS OF CASH FLOWS ................... 127 2 Page CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME ........... 128 CONSOLIDATED STATEMENTS OF SHAREHOLDER’S EQUITY ............ 129 Sierra Pacific Power Company ................................ 130 CONSOLIDATED INCOME STATEMENTS ......................... 130 CONSOLIDATED BALANCE SHEET ............................ 131 CONSOLIDATED STATEMENTS OF CASH FLOWS ................... 133 CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME ........... 134 CONSOLIDATED STATEMENTS OF SHAREHOLDER’S EQUITY ............ 135 Notes to Financial Statements ................................. 136 NOTE 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES ........... 136 NOTE 2. SEGMENT INFORMATION ............................ 143 NOTE 3. REGULATORY ACTIONS ............................. 146 NOTE 4. INVESTMENTS IN SUBSIDIARIES & OTHER PROPERTY .......... 160 NOTE 5. JOINTLY OWNED FACILITIES ......................... 161 NOTE 6. LONG-TERM DEBT ............................... 162 NOTE 7. FAIR VALUE OF FINANCIAL INSTRUMENTS ................. 168 NOTE 8. DEBT COVENANT AND OTHER RESTRICTIONS .............. 168 NOTE 9. DERIVATIVES AND HEDGING ACTIVITIES .................. 172 NOTE 10. INCOME TAXES (BENEFITS)......................... 175 NOTE 11. RETIREMENT PLAN AND POST-RETIREMENT BENEFITS ........ 181 NOTE 12. STOCK COMPENSATION PLANS ....................... 188 NOTE 13. COMMITMENTS AND CONTINGENCIES ................... 193 NOTE 14. COMMON STOCK AND OTHER PAID-IN CAPITAL ............ 199 NOTE 15. EARNINGS PER SHARE (NVE) ....................... 200 NOTE 16. ASSETS HELD FOR SALE .......................... 201 NOTE 17. SEVERANCE PROGRAMS ........................... 202 NOTE 18. QUARTERLY FINANCIAL DATA (UNAUDITED)............... 203 ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE ..................................................