Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Gutierrez Mauricio
   2. Issuer Name and Ticker or Trading Symbol
NRG ENERGY, INC. [NRG] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Sr VP, Commercial Operations
(Last)
(First)
(Middle)
NRG ENERGY, INC., 211 CARNEGIE CENTER		 3. Date of Earliest Transaction (Month/Day/Year)
08/01/2008
(Street)

PRINCETON, NJ 08540		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock, par value .01 per share 08/01/2008   M   4,000 A (1) 20,368 D  
Common Stock, par value .01 per share 08/01/2008   F   1,338 D (2) 19,030 D  
Common Stock, par value .01 per share 08/01/2008   F   335 D (3) 18,695 D  

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Performance Units (1) 08/01/2008   M     4,000 08/01/2008 08/01/2008 Common Stock, par value $.01 per share 4,000 $ 0 (1) 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Gutierrez Mauricio
NRG ENERGY, INC.
211 CARNEGIE CENTER
PRINCETON, NJ 08540		       Sr VP, Commercial Operations  

Signatures

 /s/Mauricio Gutierrez   08/04/2008
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Mr. Gutierrez was issued 4,000 Performance Units by NRG Energy, Inc. under NRG Energy, Inc.'s Long Term Incentive Plan on August 1, 2005. Each Performance Unit was subject to pay out if the average closing price of NRG Energy, Inc.'s Common Stock for the ten trading days prior to August 1, 2008 (the "Measurement Price") was equal to or greater than $26.875 (the "Target Price"). The payout for each Performance Unit was equal to: (i) one share of Common Stock, if the Measurement Price equaled the Target Price; (ii) a prorated amount in between one and two shares of Common Stock, if the Measurement Price was greater than the Target Price but less than $31.50 (the "Maximum Price"); and (iii) two shares of Common Stock, if the Measurement Price was equal to or greater than the Maximum Price. On August 1, 2008 the Measurement Price was greater than the Maximum Price.
(2) Pursuant to NRG Energy, Inc.'s Long Term Incentive Plan, Mr. Gutierrez elected to satisfy his tax withholding obligation upon the exchange of common stock for Performance Units by surrendering a number of shares of common stock having a value on the date of the exchange equal to the tax withholding obligation. This reflects the surrender of 1,338 shares of common stock to satisfy the grantee's tax withholding obligation.
(3) On August 1, 2005, Mr. Gutierrez was issued 1,000 Restricted Stock Units ("RSUs") by NRG Energy, Inc. under NRG Energy, Inc.'s Long Term Incentive Plan (the "LTIP"). Each RSU is equivalent in value to one share of NRG's Common Stock, par value $0.01. On August 1, 2008, all of the originally granted RSUs vested. Pursuant to the LTIP, Mr. Gutierrez elected to satisfy his tax withholding obligation upon the exchange of common stock for RSUs by surrendering a number of shares of common stock having a value on the date of the exchange equal to the tax withholding obligation. This reflects the surrender of 335 shares of common stock to satisfy the grantee's tax withholding obligation.

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