Exhibit 10.2.2



                             NRG Energy, Inc.
                            1221 Nicollet Mall
                                 Suite 700
                              Minneapolis, MN

                              April 30, 1996

                                     
O'Brien Environmental Energy, Inc.
225 South Eighth Street
Philadelphia, PA  19106
                                     

Gentlemen/Ladies:

Reference is made to that certain Chapter 11 Financing  Agreement dated as
of August 30, 1995, as amended by letter Agreement dated February 20, 1996,
(the "DIP Loan Agreement") between O'Brien Environmental Energy, Inc. (the
"Company") and NRG Energy, Inc. ("NRG") and the Amended and Restated Stock
Purchase and Reorganization Agreement dated as of January 31, 1995 (the
"Acquisition Agreement") by and between the Company and NRG.  This will
confirm our agreement to amend the DIP Loan Agreement by (i) striking the
proviso that appears beginning in the seventh line of Section 1.9 of the
DIP Loan Agreement and (ii) deleting the words "making or incurring
Specified Development Costs" beginning in the fifth line of Section 6(b) of
the DIP Loan Agreement and replacing them with the following: "making
capital contributions or incurring development costs in connection with the
projects commonly referred to as Edgeboro or Grays Ferry" (it being agreed
and understood that, in view of the possible increase to the Cash Purchase
Price (as defined in the Acquisition Agreement) provided for in Section 2.5
of the Acquisition Agreement in the event the Company makes capital
contributions or incurs development costs in connection with Edgeboro or
Grays Ferry using funds provided to the Company under the DIP Loan
Agreement, any provision in the DIP Loan Agreement providing for a
reduction in the amount to be repaid in respect of any DIP Loan would be
duplicative of or otherwise inconsistent with Section 2.5 of the
Acquisition Agreement.  Except as expressly set forth above herein, this
letter amendment does not amend or otherwise affect the DIP Loan Agreement,
which shall continue in full force and effect.

If the foregoing accurately sets forth our agreement with respect to the
subject matter hereof, please sign in the place indicated below and return
an original of this letter agreement, as signed, to the undersigned.



O'Brien Environmental Energy, Inc.
[Dated as of the Closing Date]
Page 2


                         NRG Energy, Inc.
                              
                              By: /s/ Craig A. Mataczynski
                              Title:  Vice President
                              
                              
ACCEPTED AND AGREED TO:

O'BRIEN ENVIRONMENTAL ENERGY, INC.

By: /s/ John B. Kelly

As of the date set forth above.