Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF 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
OMB APPROVAL
OMB Number: 3235-0104
Expires: January 31, 2005
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
  TPG Advisors IV, Inc.
2. Date of Event Requiring Statement (Month/Day/Year)
08/09/2006
3. Issuer Name and Ticker or Trading Symbol
NRG ENERGY, INC. [NRG]
(Last)
(First)
(Middle)
C/O TEXAS PACIFIC GROUP, 301 COMMERCE STREET, SUITE 3300
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) __X__ Other (specify below)
See Remarks
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

FORT WORTH, TX 76102
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 Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common stock, par value $0.01 per share 5,068,444
I
Through funds managed by the Reporting Person; see footnotes (1) (2)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
TPG Advisors IV, Inc.
C/O TEXAS PACIFIC GROUP
301 COMMERCE STREET, SUITE 3300
FORT WORTH, TX 76102
    X   See Remarks

Signatures

/s/ David A. Spuria, Vice President, on behalf of TPG Advisors IV, Inc. 08/11/2006
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(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) TPG Advisors IV, Inc. (the "Reporting Person") is the general partner of TPG GenPar IV, L.P., which in turn is the general partner of TPG Partners IV - AIV 1, L.P. and TPG Partners IV - AIV 2, L.P. (together, the "TPG Funds"). Collectively, the TPG Funds directly hold 5,068,444 shares of NRG Energy, Inc.'s common stock (the "Common Stock").
(2) The Reporting Person is deemed to be the beneficial owner of the Common Stock beneficially owned by the TPG Funds only to the extent of the greater of its direct or indirect interest in the profits or capital accounts of such TPG Funds. Pursuant to Rule 16a-1(a)(4) under the Securities and Exchange Act (the "Exchange Act"), this filing shall not be deemed an admission that the Reporting Person is, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owner of any securities beneficially owned by the TPG Funds in excess of such amount. The shareholders of the Reporting Person are David Bonderman, James G. Coulter and William S. Price, III (collectively, the "Shareholders"). Each Shareholder disclaims beneficial ownership of any of the Common Stock reported herein.
 
Remarks:
As described in Amendment No. 1 to Schedule 13D filed on August 11, 2006 with respect to the Common Stock by the Reporting Person and the other filers listed on the signature pages thereto (the "Other 13D Filers"), the TPG Funds and certain Other 13D Filers may be deemed to be a "group" under Section 13(d) of the Securities Exchange Act and the Reporting Person may be deemed to have beneficial ownership of 10% or more of the Common Stock.  Each of the TPG Funds and the Reporting Person expressly disclaims membership in any such group under Section 13(d) of the Securities Exchange Act or for any other purpose.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.