Sec Form 4 Filing - HUTH JOHANNES P @ NRG ENERGY, INC. - 2006-08-15

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 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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1. Name and Address of Reporting Person HUTH JOHANNES P 2. Issuer Name and Ticker or Trading Symbol NRG ENERGY, INC. [ NRG] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director X __ 10% Owner _____ Officer (give title below) X __ Other (specify below) See Remarks (Last) (First) (Middle) C/O KOHLBERG KRAVIS ROBERTS & CO. L.P., 9 WEST 57TH STREET 3. Date of Earliest Transaction (MM/DD/YY) 08/15/2006 (Street) NEW YORK, NY10019 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) _____ Form filed by One Reporting Person __ X __ 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 (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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 $0.01 per share 08/15/2006 S 4,099,941 D $ 48.41 ( 1 ) 4,099,941 I See footnotes ( 1 ) ( 2 ) ( 3 ) ( 4 ) ( 5 ) Common Stock, par value $0.01 per share 08/15/2006 S 215,786 D $ 48.41 ( 1 ) 215,786 I See footnotes ( 1 ) ( 2 ) ( 3 ) ( 4 ) ( 5 )

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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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 (MM/DD/YY) 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

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other HUTH JOHANNES P C/O KOHLBERG KRAVIS ROBERTS & CO. L.P. 9 WEST 57TH STREET NEW YORK, NY10019 X See Remarks LIPSCHULTZ MARC S C/O KOHLBERG KRAVIS ROBERTS & CO. L.P. 9 WEST 57TH STREET NEW YORK, NY10019 X See Remarks MICHELSON MICHAEL W C/O KOHLBERG KRAVIS ROBERTS & CO. L.P. 9 WEST 57TH STREET NEW YORK, NY10019 X See Remarks NAVAB ALEXANDAR JR C/O KOHLBERG KRAVIS ROBERTS & CO. L.P. 9 WEST 57TH STREET NEW YORK, NY10019 X See Remarks RAETHER PAUL E C/O KOHLBERG KRAVIS ROBERTS & CO. L.P. 9 WEST 57TH STREET NEW YORK, NY10019 X See Remarks Signatures /s/ William J. Janetschek, by power of attorney for all Reporting Persons 08/16/2006 Signature of Reporting Person Date

Explanation of Responses:

( 1 )On August 15, 2006, KKR Millennium Fund (Energy) L.P. ("Millennium Energy") and KKR Partners III, L.P. (Series I) ("KKR Partners" and together with Millennium Energy, the "KKR Funds") sold respectively 4,099,941 and 215,786 shares (4,315,727 shares in total) of NRG Energy, Inc.'s common stock (the "Common Stock"), to Morgan Stanley & Co. Incorporated at a price of $48.41 per share (the "Resale"). Following completion of the Resale, Millennium Energy and KKR Partners directly own respectively 4,099,941 and 215,786 shares of Common Stock reported as beneficially owned in the above table. ( 2 )As general partner of Millennium Energy, KKR Associates Millennium (Energy) L.P. ("KKR Associates") may be deemed to be the beneficial owner of the Common Stock held by Millennium Energy. As the general partner of KKR Associates, KKR Millennium GP (Energy) LLC ("KKR GP LLC") also may be deemed to be the beneficial owner of the Common Stock held by Millennium Energy. As general partner of KKR Partners, KKR GP LLC may be deemed to be the beneficial owner of the Common Stock held by KKR Partners. ( 3 )Henry R. Kravis, George R. Roberts, Todd A. Fisher, Jacques Garaialde, Perry Golkin, James H. Greene, Jr., Johannes P. Huth, Marc S. Lipschultz, Michael W. Michelson, Alexander Navab and Paul E. Raether are the members of KKR GP LLC (the "Members"), and as such may be deemed to share beneficial ownership of any Common Stock that KKR GP LLC may be deemed to beneficially own. Each Reporting Person disclaims beneficial ownership of the Common Stock, except to the extent of its or his pecuniary interest therein. ( 4 )The filing of this statement shall not be deemed an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, any Reporting Person is the beneficial owner of any Common Stock covered by this statement. ( 5 )Due to limitations on Form 4, certain persons described as beneficial owners or deemed beneficial owners of the securities reported on this Form 4 are filing as reporting persons on a separate Form 4.

Remarks: As described in Amendment No. 1 to Schedule 13D ("Amendment No. 1") filed on August 11, 2006 with respect to the Common Stock by the KKR Funds, KKR GP LLC, KKR Associates and the other filers listed on the signature pages thereto, as of the date of Amendment No. 1, the KKR Funds and certain other Funds (as defined in Amendment No. 1) may have been deemed to be a "group" under Section 13(d) of the Securities Exchange Act and accordingly each Reporting Person may have been deemed to have beneficial ownership of 10% or more of the Common Stock. Following the completion of the Resale, the Reporting Persons are not presently acting in a manner that could deem them to be a "group" with the other Funds within the meaning of Section 13(d) of the Securities Exchange Act with respect to the Common Stock. Each Reporting Person expressly disclaims membership in any such group for the purposes of Section 13(d) of the Securities Exchange Act or for any other purpose. Exhibit 24 - Powers of Attorney Exhibit 99 - Joint Filer Information

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

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