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                                                                EXHIBIT 99.23



                               SIXTH AMENDMENT TO
                           1988 AMENDED AND RESTATED
                      NUCLEAR FUEL HEAT PURCHASE CONTRACT


     Sixth Amendment, dated as of August 28, 1997 (this "Sixth Amendment"), to
the 1988 Amended and Restated Nuclear Fuel Heat Purchase Contract dated as of
October 4, 1988, as amended by First, Second, Third, Fourth and Fifth
Amendments thereto dated as of February 1, 1990, September 1, 1993, August 31,
1994, March 8, 1996 and August 29, 1996 respectively (as so amended, the
"Contract"), between RENAISSANCE ENERGY COMPANY, a Delaware corporation ("Fuel
Company") and THE DETROIT EDISON COMPANY, a Michigan corporation ("Utility").

                              W I T N E S S E T H:


     Whereas, the Fuel Company is a party to (i) a $200,000,000 364 Day Credit
Agreement dated as of September 1, 1993, as amended by a First Amendment
thereto dated as of September 1, 1994, extension letters from the Banks to the
Fuel Company dated June 30, 1995, a Third Amendment thereto dated March 8, 1996
and a Fourth Amendment thereto dated August 29, 1996, among the Fuel Company,
the Utility, Barclays Bank PLC, New York Branch, as agent (the "Agent") and the
banks signatory thereto (the "Banks") (as so amended, the "364 Day Credit
Agreement"); and (ii) a $200,000,000 Multi-Year Credit Agreement dated as of
September 1, 1993, as amended by a First Amendment thereto dated as of
September 1, 1994, extension letters from the Banks to the Fuel Company dated
June 30, 1995, a Third Amendment thereto, dated March 8, 1996 and a Fourth
Amendment thereto, dated September 1, 1996, among the Fuel Company, the
Utility, the Agent and the Banks (as so amended, the "Multi-Year Credit
Agreement"; the 364 Day Credit Agreement and the Multi-Year Credit Agreement,
collectively, the "Credit Agreement");

     Whereas, each of the 364 Day Credit Agreement and the Multi-Year Credit
Agreement, respectively, are being amended by Fifth Amendments thereto
(collectively, the "Credit Agreement Amendments");

     Whereas, it is a condition precedent to the effectiveness of the Credit
Agreement Amendments that the Utility and Fuel Company enter into this Sixth
Amendment.


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     NOW, THEREFORE, in consideration of the mutual covenants and agreements
hereinafter set forth, the Fuel Company and the Utility agree as follows:

     Section 1. Defined Terms.  All capitalized terms used herein and not
defined shall have the meanings ascribed to such terms in the Contract.

     Section 2. Amendments to Contract.  Section 2(b) of the Contract is hereby
amended to read in its entirety as follows:

         "(b) The term of this Contract shall, unless sooner terminated 
pursuant to the provisions hereof, end at 12:00 midnight, New York time, on the
Expiration Date.  The Expiration Date in effect on the date hereof is
August 27, 1998. Subject to the proviso below, the Utility shall have the right
to renew this Contract for subsequent terms by designating in writing to the
Fuel Company, within 90 days prior to the then current Expiration Date, a new
Expiration Date; provided, however, that the Expiration Date for such renewal
term shall be, (i) in the event the Michigan Public Service Commission (the
"MPSC") has authorized this Contract, not later than  September 1, 2001 (an
"Outside Expiration Date") or (ii) if the MPSC has not authorized this
Contract, not later than the earlier to occur of the Outside Expiration Date
and twelve months from the then current Expiration Date; and provided, further,
that (i) no material adverse change shall have occurred (except such as may
have occurred in the ordinary course of the Utility's business) in the
financial condition or results of operations of Utility since the most recent
financial statements of the Utility delivered to the Borrower, and (ii) no
Event of Default (as defined herein or as defined in any Credit Agreement) or
other event which with the giving of notice or lapse of time, or both, would
constitute such an Event of Default shall have occurred and be continuing."

     Section 3. Miscellaneous.

         (a) Each of Utility and Fuel Company hereby represents and warrants as
to itself that this Sixth Amendment has been duly authorized by all necessary   
corporate action on its part and this Sixth Amendment has been duly and validly
executed and delivered by itself and constitutes its respective legal, valid
and binding obligation, enforceable in accordance with the terms of this Sixth
Amendment.



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         (b) Except as amended hereby, the terms of the Contract shall 
continue in full force and effect and is hereby ratified and confirmed in
all respects as so amended.

         (c) This Sixth Amendment shall be governed by and construed in 
accordance with the laws of the State of New York without reference to
principles of conflicts of laws.

         (d) This Sixth Amendment may be signed in any number of counterparts 
with the same effect as if the signatures thereto and hereto were upon the
same instrument.

     IN WITNESS WHEREOF, Utility and Fuel Company have caused this Sixth
Amendment to be duly executed by their duly authorized officers, all as of the
day and year first above written.


                                        RENAISSANCE ENERGY COMPANY



                                        By:________________________
                                        Title:


                                        THE DETROIT EDISON COMPANY



                                        By:________________________
                                        Title:




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