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                                                            Exhibit 10.22.2


                           CONSENT TO ASSIGNMENT
                                    OF
                SYSTEM OPERATING AND MAINTENANCE AGREEMENT


      This Consent to Assignment (this "Consent") is entered into as May 1,
1996  by Stewart & Stevenson Operations, Inc., a Delaware Corporation  (the
"Company"),  NRG Generating (Parlin) Cogeneration Inc. (formerly  known  as
O'Brien   (Parlin)  Cogeneration,  Inc.),  a  Delaware  Corporation   ("NRG
Parlin"), and Credit Suisse, a bank organized and existing under  the  laws
of  Switzerland,  acting  through  its New  York  branch  ("CS")  as  agent
(hereinafter in such capacity, together with any successors thereto in such
capacity referred to as "Agent") pursuant to the credit Agreement dated  as
May  1,  1996  by  and  among (i) NRG Parlin and  NRG  Generating  (Newark)
Cogeneration Inc. (formerly known as O'Brien (Newark) Cogeneration,  Inc.),
a Delaware Corporation ("NRG Newark") (collectively, the "Borrowers"), (ii)
Credit Suisse, as Lender and each additional Lender from time to time party
to  the  Credit Agreement and_(iii), the Agent, (as to same may be amended,
modified or supplemented from time to time, the "Credit Agreement").

                                 RECITALS

      WHEREAS,  the  Company and NRG Parlin have entered  into  the  System
Operating and Maintenance Agreement, dated as of May 1, 1996 (as  the  same
may  be  amended, modified or supplemented from time to time, the "Assigned
Agreement"); and

      WHEREAS,  NRG  Parlin has assigned or will assign to  Agent  for  the
benefit  of  the  Secured Parties (as defined in the Credit  Agreement  and
referred to herein as "Assignee") all of its rights, title and interest in,
to   and  under  the  Assigned  Agreement  as  security  for  NRG  Parlin's
obligations under the Credit Agreement; and

      WHEREAS, the Company is willing to consent to such assignment and the
grant  of  a  security  interest by NRG Parlin  in  favor  of  Assignee  as
described above.

     NOW, THEREFORE, in consideration of the premises and of other valuable
consideration, the parties hereto agree as follows:

     1.   Assignment and Security Interest

     As security for the due and punctual performance and payment of all of
NRG  Parlin's  obligations  under  the Credit  Agreement,  NRG  Parlin  has
assigned  or  will assign to Assignee as collateral security,  all  of  NRG
Parlin's  rights  to and under the Assigned Agreement upon  the  terms  set
forth in the Security Agreement (as defined in the Credit Agreement).

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     2.   Consent

      The  Company  hereby  (i)  irrevocably  consents  to  the  assignment
specified  in paragraph 1 of this Consent and to any subsequent assignments
by  Agent or Assignee upon and after the Agent's or Assignee's exercise  of
its  rights and remedies under the security Agreement and (ii) agrees that,
following  the assumption of the Assigned Agreement by Agent,  Assignee  or
their  nominee,  designee  or  assignee, all  representations,  warranties,
indemnities and agreements (other than those representations and warranties
expressly  made  only as of an earlier date) made by the Company  under  or
pursuant to the Assigned Agreement shall inure to the benefit of such party
and  shall be enforceable by such party to the same extent as if such party
were originally, named in the, Assigned Agreement.

     3.   Default and Cure

      (a)   If NRG Parlin defaults under the Assigned Agreement the Company
shall,  before  terminating the Assign Agreement or  exercising  any  other
remedy,  give written notice to Agent specifying the default and the  steps
necessary to cure the same and Agent or Assignee shall have sixty (60) days
(30  days in the case of a default in payment by NRG Parlin) after  receipt
of  such  notice  (or  such  longer period of time  as  may  be  reasonably
necessary  under  the  circumstances, provided that Agent  or  Assignee  is
diligently pursuing such cure) to cure such default or to cause  it  to  be
cured.   If Agent and Assignee fail to cure or cause to be cured  any  such
default  within the appropriate period set forth above, the  Company  shall
have  all  of its rights and remedies with respect to such default  as  set
forth in the Assigned Agreement and at law or in equity.

      (b)   In  the  event  that the Assigned Agreement  is  terminated  by
rejection,  or otherwise, during a case in which NRG Parlin is  the  debtor
under Title 11, United States Code, or other similar federal state statute,
then the Company shall, at the option of Agent and Assignee and so long  as
all  existing  payment defaults by NRG Parlin under the Assigned  Agreement
are cured by Agent, Assignee or their nominee or designee, enter into a new
Assigned  Agreement with Agent, Assignee or (at the direction of  Agent  or
Assignee) their nominee or designee having terms substantially identical to
the  Assigned Agreement, pursuant to which Agent, Assignee or their nominee
or  designee  shall have all of the rights and obligations  of  NRG  Parlin
under the Assigned Agreement.

(c)  If Agent notifies the Company in writing that NRG Parlin has defaulted
     under  the  Credit  Agreement and requests that the  Company  continue
     performance under the Assigned Agreement, the Company shall thereafter
     perform under the Assigned Agreement in accordance with its terms,  so
     long  as  all  existing  defaults by NRG  Parlin  under  the  Assigned
     Agreement are cured by Agent, Assignee or

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     their nominee or designee and the obligations of NRG Parlin thereunder
     shall continue to be paid and performed by NRG Parlin, Agent, Assignee
     or their nominee or designee.

     4.   Payments

     The  Company  agrees that until receipt of written notice  from  Agent
that  all  obligations of NRG Parlin under the Credit Agreement  have  been
fully satisfied, the Company hereby agrees to make all payments due to  NRG
Parlin  under the Assigned Agreement directly to such account as Agent  may
from time to time hereafter specify in writing and the Company will not  be
entitled to recover any amount so paid from Agent.

     5.   Delivery of Notices

     The Company agrees that it will promptly notify Agent of any breach by
NRG  Parlin of any of the terms of the Assigned Agreement and will  deliver
to  Agent  simultaneously with the delivery thereof to NRG Parlin  (i)  any
notices delivered pursuant to the Assigned Agreement or otherwise and  (ii)
all  invoices, budgets, plans and reports delivered pursuant to Article  VI
of the Assigned Agreement.

     6.   Liability of Assignee

     The  Company acknowledges and agrees that Agent and Assignee have  not
assumed  and  do not have any obligation or liability under or pursuant  to
the  Assigned Agreement, and that the exercise by Agent or Assignee of  its
rights  and  remedies under the Security Agreement shall not constitute  an
assumption of NRG Parlin's obligations under the Assigned Agreement (except
to  the extent such obligations shall be expressly assumed by an instrument
in writing executed by the Agent or Assignee).

     7.   Amendment or Termination of Assigned Agreement

     The  Company  covenants and agrees with Agent that without  the  prior
written consent of Agent (i) the Company will not materially amend, modify,
terminate  (prior  to  the  expiration of the applicable  cure  periods  in
Section  3  hereof) or assign, transfer or encumber any of its interest  in
the  Assigned  Agreement and (ii) no waiver by NRG Parlin  of  any  of  the
obligations  of the Company under the Assigned Agreement, and  no  consent,
approval  or  election made by .NRG Parlin in connection with the  Assigned
Agreement shall be effective as against Agent and Assignee.

     8.   Representations and Warranties

     The Company hereby represents and warrants to Agent and Assignee as
follows:

     (a)  The company is a corporation duly organized, validly

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existing and in good standing under the laws of the State of Delaware.  The
Company  has full power, authority and legal right to incur the obligations
provided for in this Consent and the Assigned Agreement.

      (b)   The execution, delivery and performance by the Company of  this
Consent  and  the  Assigned  Agreement have been  duly  authorized  by  all
necessary corporate action.

     (c)   The  Assigned Agreement is in full force and effect and has  not
been  amended,  and  no default has occurred or exists under  the  Assigned
Agreement  and  no  event  or  condition has occurred,  or  exists  and  is
continuing  which  with the lapse of time, the giving of  notice,  or  both
would constitute such a default under the Assigned Agreement.

      (d)  Each of this Consent and the Assigned Agreement constitutes  the
legal, valid and binding obligation of the Company enforceable against, the
Company  in  accordance  with  its terms, except  as  enforceability  maybe
limited  by  general  principles of equity and  by  applicable  bankruptcy,
insolvency,   moratorium  or  similar  laws  affecting   creditors   rights
generally.

      (e)   All representations and warranties made by the Company  in  the
Assigned Agreement were true and correct in all material respects on and as
of the date when made and, except for those that by their terms speak as of
a specific date, are true and correct in all material respects on and as of
this Consent.

     (f)   No consent, approval, order or authorization of or registration,
declaration  of  a  filing with, or giving of notice to, obtaining  of  any
license  or  permit from, or taking any other action with respect  to,  any
federal,  state or local government or public body, authority or agency  is
required  in  connection with the valid authorization, execution,  delivery
and performance of this Consent or the Assigned Agreement.

     (g)  There is no litigation, action, suit, investigation or proceeding
pending  or,  to the best knowledge of the Company, threatened against  the
Company  nor  any  basis  therefor, before or by any court,  administrative
agency,  environmental council, arbitrator or governmental authority,  body
or  agency, which could adversely affect the performance by the Company  of
its  obligations  hereunder  or  under  the  Assigned  Agreement  or  which
questions the validity, binding effect or enforceability hereof or  thereof
or any of the transactions contemplated hereby or thereby.

     (h)  The  company is not in violation of its articles of incorporation
or  bylaws,  and the execution, delivery and performance by the Company  of
this  Consent  and  the  Assigned Agreement, and the  consummation  of  the
transactions  contemplated  hereby and thereby,  will  not  result  in  any
violation of any term of

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its  articles  of  . incorporation or bylaws, of any material  contract  or
agreement applicable to it, or of any license, permit, franchise, judgment,
decree,   writ,  injunction,  order,  charter,  law,  ordinance,  rule   or
regulation  applicable to it or any of its properties or to any obligations
incurred  by  it or by which it or any of its properties may  be  bound  or
affected, or of any determination or award of any arbitrator applicable  to
it, and will not conflict with, or cause a breach of, or default under, any
such .term or result in the creation of any lien upon any of its properties
or assets.

      (i)   The  Company  has not received notice of, or consented  to  the
assignment of any of NRG Parlin's right, title, or interest in the Assigned
Agreement to any person or entity other than Agent and Assignee.

     9.   Notices

     All  notices  or other communications which are required or  permitted
hereunder to be given to any party shall be in writing (including facsimile
communication) and shall be deemed given if delivered personally or sent by
telecopy  or  by registered or certified mail, return receipt requested  to
the  address of such party specified below or to such other address as  the
addressee  may  have  specified in a notice duly given  to  the  sender  as
provided herein:

If to Agent:

               Credit Suisse
               Tower 49
               12 East 49th Street
               New York, NY  10071
               Attention:  Project Finance
               Telecopy:  (212) 238-5390


If to NRG Parlin:

               NRG Generating (Parlin) Cogeneration Inc.
               c/o NRG Energy, Inc.
               1221 Nicollet Mall Suite 700
               Minneapolis, MN 55403
               Attention:
               Telecopy:

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If to the Company:

               Stewart & Stevenson Operations, Inc-
               2707 North Loop West
               Houston, TX 77008
               Attention: Vice President - North American
                          Operations
               Telecopy: (713) 863-8047


with a copy to:

               Stewart & Stevenson Services, Inc.
               2707 North Loop West.
               Houston TX 77008
               Attention: Group Vice President - EPS
               Telecopy: (713) 869-4068


All  such notices and communications shall, when mailed, be effective seven
(7)  days  after  being after being deposited in the  mail  in  the  manner
aforesaid, or when sent by telecopier, upon receipt thereof.

     10.  Governing Law

      THIS CONSENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH
THE LAWS OF THE STATE OF NEW YORK (WITHOUT GIVING EFFECT TO THE PRINCIPLES
THEREOF RELATING TO CONFLICTS OF LAW EXCEPT SECTION 5-1401 OF THE NEW YORK
GENERAL OBLIGATIONS LAW).

     11.  Successors and Assigns

      This  Consent shall be binding upon the parties and their  successors
and  assigns  and inure to the benefit of the parties and their  respective
successors  and assigns (which assigns, in the case of Agent and  Assignee,
shall  include, without limitation, any nominee or designee  of  Agent  and
Assignee  and  any  purchaser of all or any portion  of  rights  under  the
Assigned Agreement in connection with an Event of Default under the  Credit
Agreement or a foreclosure by Agent and Assignee.)

     12.  Waiver

     No  amendment  or  waiver of any Provisions of this Consent  shall  be
effective unless the same shall be in writing and signed by Agent, and then
such waiver or consent shall be effective only in the specific instance and
for the specific purpose for which given.
     
     13.  Counterparts
     
     This  Consent  may be executed in any number of counterparts,  all  Of
which counterparts shall together constitute one and the same instrument.

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     14.  Further Assurances

     The  Company will at any time and from time to time, upon the  written
request  of Agent, execute and deliver such further documents and  do  such
other  acts  and  things  as  Agent  may reasonably  request  in  order  to
effectuate more fully the purposes of this Consent.

     15.  Conflicts

     In the event of a conflict between any provision of this Consent and
the provisions of the Assigned Agreement, the provisions of this Consent
shall prevail.

     IN WITNESS WHEREOF, each of the undersigned has duly executed this
Consent as of the date first above written.


                              STEWART & STEVENSON OPERATIONS, INC.

                              By: /s/ Harvey Braswell
                              Name:
                              Title:


                              NRG GENERATING (PARLIN) COGENERATION, INC.
                              By: /s/ Leonard Bluhm
                              Name:
                              Title:


Accepted:

CREDIT SUISSE, as Agent

By:  /s/ Louis Iaconetti
Name:  Louis D. Iaconetti
Title: Associate


By:  /s/ Steven Dowe
Name:  Steven Dowe
Title: Associate

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