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OMB APPROVAL
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OMB Number:             3235-0145
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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 1)*

NRG Energy, Inc.
-------------------------------------------------------------------------------
(Name of Issuer)

Common Stock, par value $0.01
-------------------------------------------------------------------------------
(Title of Class of Securities)

629377508
--------------------------------------------
(CUSIP Number)

December 31, 2005
-------------------------------------------------------------------------------
(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

[X] Rule 13d-1(b)

[_] Rule 13d-1(c)

[_] Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting  person's
initial  filing on this form with respect to the subject  class of  securities,
and for any subsequent  amendment  containing  information which would alter the
disclosures provided in a prior cover page.

The  information  required  in the  remainder  of this  cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities  Exchange
Act of 1934 ("Act") or otherwise  subject to the liabilities of that section of
8the Act but shall be subject to all other provisions of the Act (however,  see
the Notes).

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.

SEC 1745 (1-06)

Page 1 of 8 pages

-----------------------
CUSIP No. 629377508                   13G
-----------------------

------------------------------------------------------------------------------
1.   Name of Reporting Person
I.R.S. Identification No. of above Person

Goldman, Sachs & Co.

------------------------------------------------------------------------------
2.   Check the Appropriate Box if a Member of a Group
(a) [_]
(b) [_]

------------------------------------------------------------------------------
3.   SEC Use Only

------------------------------------------------------------------------------
4.   Citizenship or Place of Organization

New York

------------------------------------------------------------------------------
5.   Sole Voting Power

Number of                 0

Shares        ----------------------------------------------------------
6.   Shared Voting Power
Beneficially      
474,871
Owned by
----------------------------------------------------------
Each          7.   Sole Dispositive Power

Reporting                  0

Person        ----------------------------------------------------------
8.   Shared Dispositive Power
With:          
480,271

------------------------------------------------------------------------------
9.   Aggregate Amount Beneficially Owned by Each Reporting Person

480,271

------------------------------------------------------------------------------
10.   Check if the Aggregate Amount in Row (9) Excludes Certain Shares

[_]

------------------------------------------------------------------------------
11.   Percent of Class Represented by Amount in Row (9)

0.5%

------------------------------------------------------------------------------
12.   Type of Reporting Person

BD-PN-IA

------------------------------------------------------------------------------

Page 2 of 8 pages

-----------------------
CUSIP No. 629377508                   13G
-----------------------

------------------------------------------------------------------------------
1.   Name of Reporting Person
I.R.S. Identification No. of above Person

The Goldman Sachs Group, Inc.

------------------------------------------------------------------------------
2.   Check the Appropriate Box if a Member of a Group
(a) [_]
(b) [_]

------------------------------------------------------------------------------
3.   SEC Use Only

------------------------------------------------------------------------------
4.   Citizenship or Place of Organization

Delaware

------------------------------------------------------------------------------
5.   Sole Voting Power

Number of                 0

Shares        ----------------------------------------------------------
6.   Shared Voting Power
Beneficially      
474,871
Owned by
----------------------------------------------------------
Each          7.   Sole Dispositive Power

Reporting                  0

Person        ----------------------------------------------------------
8.   Shared Dispositive Power
With:          
480,271

------------------------------------------------------------------------------
9.   Aggregate Amount Beneficially Owned by Each Reporting Person

480,271

------------------------------------------------------------------------------
10.   Check if the Aggregate Amount in Row (9) Excludes Certain Shares

[_]

------------------------------------------------------------------------------
11.   Percent of Class Represented by Amount in Row (9)

0.5%

------------------------------------------------------------------------------
12.   Type of Reporting Person

HC-CO

------------------------------------------------------------------------------

Page 3 of 8 pages

Item 4.            Ownership.*

(a).     Amount beneficially owned:
See the response(s) to Item  9 on the attached cover page(s).

(b).     Percent of Class:
See the response(s) to Item 11 on the attached cover page(s).

(c).     Number of shares as to which such person has:

(i).     Sole power to  vote or to direct  the vote:  See the
response(s) to Item 5 on the attached cover page(s).

(ii).    Shared power to vote or to direct the vote:  See the
response(s) to Item 6 on the attached cover page(s).

(iii).   Sole power to  dispose or to direct  the disposition
of:  See the response(s) to  Item 7  on the attached
cover page(s).

(iv).    Shared power to dispose or to direct the disposition
of:  See the response(s) to  Item 8  on the attached
cover page(s).

Item 5.            Ownership  of Five  Percent or  Less  of a  Class.
If this  statement  is being filed to report the fact that as
of the date hereof the  reporting  persons  have ceased to be
the beneficial  owners of more than five percent of the class
of securities, check the following [X].

Item 10.           Certification.  
By signing  below I certify that, to the best of my knowledge
and belief,  the  securities  referred to above were acquired
and are held in the ordinary  course of business and were not
acquired  and are not  held  for the  purpose  of or with the
effect of changing or  influencing  the control of the issuer
of the  securities  and were not acquired and are not held in
connection with or as a participant in any transaction having
that purpose or effect.

--------------------------
* In accordance with the Securities and Exchange Commission (the "SEC")
Release No.  34-39538  (January 12, 1998),  this filing  reflects the securities
beneficially  owned by the investment  banking  division  ("IBD") of The Goldman
Sachs Group,  Inc. and its  subsidiaries and affiliates  (collectively,  "GSG").
This filing does not reflect securities, if any, beneficially owned by any other
operating  unit of GSG. IBD  disclaims  beneficial  ownership of the  securities
beneficially  owned by (i) any client  accounts with respect to which IBD or its
employees  have  voting  or  investment  discretion,  or both and  (ii)  certain
investment  entities,  of which IBD is the  general  partner,  managing  general
partner or other manager,  to the extent  interests in such entities are held by
persons other than IBD.

Page 4 of 8 pages

SIGNATURE

After reasonable inquiry and to the best of my knowledge
and belief,  I certify that the information set forth in
this statement is true, complete and correct.

Date:  February 6, 2006

THE GOLDMAN SACHS GROUP, INC.

By: /s/ Yvette Kosic
-------------------------------------------
Name:   Yvette Kosic
Title:  Attorney-in-fact

GOLDMAN, SACHS & CO.

By: /s/ Yvette Kosic
-------------------------------------------
Name:   Yvette Kosic
Title:  Attorney-in-fact

Page 5 of 8 pages

INDEX TO EXHIBITS

Exhibit No.             Exhibit
-----------             -------

99.1                 Power of Attorney,  dated November 7th, 2005, relating to
Goldman, Sachs & Co.

99.2                 Power of Attorney,  dated November 7th, 2005, relating to
The Goldman Sachs Group, Inc.

Page 6 of 8 pages

(EXHIBIT 99.1)

POWER OF ATTORNEY

KNOW  ALL  PERSONS  BY  THESE  PRESENTS  that  GOLDMAN,  SACHS  & CO.  (the
"Company")  does hereby make,  constitute and appoint each of Roger S. Begelman,
Yvette  Kosic,  John M.  O'Rourke,  Felicia J. Rector,  Michael T.  Seeley,  and
Stephen Wong, (and any other employee of The Goldman Sachs Group, Inc. or one of
its affiliates  designated in writing by one of the  attorneys-in-fact),  acting
individually,  its true and lawful  attorney,  to execute and deliver in it name
and  on  its  behalf   whether  the  Company  is  acting   individually   or  as
representative of others, any and all filings required to be made by the Company
under the Securities Exchange Act of 1934, (as amended, the "Act"), with respect
to securities which may be deemed to be beneficially  owned by the Company under
the Act, giving and granting unto each said attorney-in-fact power and authority
to act in the  premises as fully and to all intents and  purposes as the Company
might or could do if personally  present by one of its  authorized  signatories,
hereby ratifying and confirming all that said attorney-in-fact shall lawfully do
or cause to be done by virtue hereof.

THIS POWER of ATTORNEY  shall  remain in full force and effect until either
revoked  in  writing  by the  undersigned  or until  such time as the  person or
persons to whom power of  attorney  has been  hereby  granted  cease(s) to be an
employee of The Goldman Sachs Group, Inc. or one of its affiliates.

IN WITNESS  WHEREOF,  the undersigned has duly subscribed these presents as
of November 7th, 2005.

GOLDMAN, SACHS & CO.

By: /s/ Gregory  K. Palm
----------------------------
GREGORY K. PALM
Managing Director

Page 7 of 8 pages

EXHIBIT (99.2)

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS that THE GOLDMAN SACHS GROUP,  INC. (the
"Company")  does hereby make,  constitute and appoint each of Roger S. Begelman,
Yvette  Kosic,  John M.  O'Rourke,  Felicia J. Rector,  Michael T.  Seeley,  and
Stephen Wong, (and any other employee of The Goldman Sachs Group, Inc. or one of
its affiliates  designated in writing by one of the  attorneys-in-fact),  acting
individually,  its true and lawful  attorney,  to execute and deliver in it name
and  on  its  behalf   whether  the  Company  is  acting   individually   or  as
representative of others, any and all filings required to be made by the Company
under the Securities Exchange Act of 1934, (as amended, the "Act"), with respect
to securities which may be deemed to be beneficially  owned by the Company under
the Act, giving and granting unto each said attorney-in-fact power and authority
to act in the  premises as fully and to all intents and  purposes as the Company
might or could do if personally  present by one of its  authorized  signatories,
hereby ratifying and confirming all that said attorney-in-fact shall lawfully do
or cause to be done by virtue hereof.

THIS POWER of ATTORNEY  shall  remain in full force and effect until either
revoked  in  writing  by the  undersigned  or until  such time as the  person or
persons to whom power of attorney  has been  hereby  granted  cease(s) to be an
employee of The Goldman Sachs Group, Inc. or one of its affiliates.

IN WITNESS  WHEREOF,  the undersigned has duly subscribed these presents as
of November 7th, 2005.

THE GOLDMAN SACHS GROUP, INC.

By: /s/ Gregory  K. Palm
----------------------------
GREGORY K. PALM
Executive Vice President and General Counsel

Page 8 of 8 pages