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                                                            Exhibit 10.21.3
                                     
                                     
                ASSIGNMENT OF ELECTRICITY PURCHASE CONTRACT
                                     
     The ASSIGNMENT OF ELECTRICITY PURCHASE CONTRACT ("Assignment"), dated
as of April 30, 1996, by and between E.I. DU PONT DE NEMOURS AND COMPANY, a
Delaware corporation ("DuPont"), O'BRIEN (PARLIN) COGENERATION, INC., a
Delaware corporation ("O'Brien"), and NRG PARLIN INC. ("NPI").

                                 RECITALS
                                     
     A.   O'Brien and DuPont entered into that certain Electricity Purchase
Contract dated January 18, 1988 (the "Electricity Purchase Contract").

     B.   O'Brien and NPI desire that O'Brien's rights and obligations
under the Electricity Purchase Contract be assigned to NPI, and DuPont is
prepared to consent to the assignment.

     NOW, THEREFORE, in consideration of the mutual covenants and promises
herein contained, and for other good and valuable consideration, the
receipt and adequacy of which are hereby acknowledged, the parties agree as
follows:

     1.   Assignment of Electricity Purchase Contract.  O'Brien's rights
and obligations under the Electricity Purchase Contract are hereby assigned
to NPI.

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     2.   Consent of DuPont.  DuPont hereby consents to this assignment
pursuant to Article XII of the Electricity Purchase Contract, which
incorporates by reference the consent requirements of Article 12 of that
certain Steam Purchase Contract between O'Brien and DuPont dated December
8, 1986.

     3.   Acknowledgment by DuPont.  DuPont acknowledges and agrees that
this Assignment is being made "without recourse".  DuPont hereby releases
O'Brien from all obligations under the Electricity Purchase Contract, and
NPI hereby agrees to assume O'Brien's rights and obligations under said
Electricity Purchase Contract.

     4.   Amendments; Waiver.  This Agreement may not be terminated,
amended, supplemented, waived or modified except by an instrument in
writing signed by both of the parties hereto.  Any failure by either party
to enforce any provisions hereof shall not constitute a waiver by that
party of its right subsequently to enforce the same or any other provision
hereof.

     5.   Severability.  Any provision of this Agreement which is
prohibited or unenforceable in any jurisdiction shall, as to such
jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions hereof, and
any such prohibition or unenforceability in any jurisdiction shall not
invalidate or render unenforceable such provision in any other
jurisdiction.

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     6.   Governing Law.  This Assignment shall, in all respects, be
governed and construed under the laws of Delaware, including all matters of
construction, validity and performance.

     7.   Counterparts; Telefacsimile Execution.  This Agreement may be
executed in any number of counterparts, and by each of the parties on
separate counterparts, each of which, when so executed, shall be deemed an
original, but all of which shall constitute but one and the same
instrument.  Delivery of an executed counterpart of this Agreement by
telefacsimile shall be equally as effective as delivery of a manually
executed counterpart of this Agreement.  Any party delivering an executed
counterpart of this Agreement by telefacsimile also shall deliver a
manually executed counterpart of this Agreement, but the failure to deliver
a manually executed counterpart shall not affect the validity,
enforceability or binding effect of this Agreement.

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     IN WITNESS WHEREOF, the Parties have executed and delivered this
Agreement as of the date first written above.

                              E.I. DU PONT DE NEMOURS AND COMPANY


                              By:  /s/ G. Kenneth Towe
                              Name:    G. Kenneth Towe
                              Title:   Energy Sourcing Manager



                              O'BRIEN (PARLIN) COGENERATION, INC.


                              By:  /s/ Leonard Bluhm
                              Name:    Leonard A. Bluhm
                              Title:   President



                              NRG PARLIN INC.


                              By:  /s/ Craig A. Mataczynski
                              Name:    Craig Mataczynski
                              Title: