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                                                                   EXHIBIT 99.13


                                                                [EXECUTION COPY]


                                FOURTH AMENDMENT

                            364-DAY CREDIT AGREEMENT

     FOURTH AMENDMENT (this "AMENDMENT"), dated as of August 29, 1996, to the
364-DAY CREDIT AGREEMENT dated as of September 1, 1993, as amended by the First
Amendment, dated as of August 31, 1994, certain extension letters, each dated
June 30, 1995, and the Third Amendment, dated as of March 8, 1996, by and among
RENAISSANCE ENERGY COMPANY, a Delaware corporation (the "BORROWER"), THE
DETROIT EDISON COMPANY, a Michigan corporation (the "GUARANTOR"), the banks
referred to therein (the "BANKS"), and BARCLAYS BANK PLC, New York Branch, as
agent (the "AGENT") for the Banks (such Credit Agreement, as heretofore
amended, being hereinafter referred to as the "EXISTING CREDIT AGREEMENT", and,
as amended by this Amendment, as the "AMENDED CREDIT AGREEMENT" or the "CREDIT
AGREEMENT").


                              W I T N E S S E T H

     WHEREAS, the Borrower, the Guarantor, the Banks and the Agent have
previously entered into the Existing Credit Agreement; and

     WHEREAS, the Borrower, the Guarantor, the Banks and the Agent now wish to
amend the Existing Credit Agreement to extend the Termination Date described
therein;

     NOW THEREFORE, the Borrower, the Guarantor, the Banks and the Agent agree
as follows (capitalized terms used but not defined in this Amendment having the
meanings assigned them in the Existing Credit Agreement):

     SECTION a)  AMENDMENTS TO EXISTING CREDIT AGREEMENT.  a) EXTENSION OF
   TERMINATION DATE.  Effective as of the date hereof, and subject to the
   satisfaction of the conditions precedent set forth in Section 2 hereof, the
   Termination Date is hereby extended to August 28, 1997.

     b) By a Fourth Amendment thereto dated as of September 1, 1996, the 3-Year
   Credit Agreement has been renamed the"MULTI-YEAR CREDIT AGREEMENT".  From
   and after the effective date of this

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    Amendment,  all references to the "the 3-Year Credit Agreement" (or words of
    like import) contained in the Financing Documents, any amendment thereto or
    any document delivered thereunder, whether executed or delivered before or
    after the effective date of this Amendment, shall be deemed to be references
    to the Multi-Year Credit Agreement, except where (and then only to the
    extent that) to do so would adversely affect the validity or effectiveness
    thereof.

     SECTION 1.  Conditions of Effectiveness.  THIS AMENDMENT SHALL BECOME
EFFECTIVE AS OF THE DATE SET FORTH ABOVE WHEN, AND ONLY WHEN, THE AGENT SHALL
HAVE RECEIVED (IN SUFFICIENT COPIES FOR EACH BANK) THE FOLLOWING:


           a) Counterparts of this Amendment executed by the Borrower, the
         Guarantor and all of the Banks.

           b) Certified copies of the resolutions of the Board of Directors of
         the Borrower authorizing this Amendment and of all documents
         evidencing other necessary corporate action and governmental and
         regulatory approvals required to be obtained by it in connection
         therewith, certified by the Secretary or Assistant Secretary of the
         Borrower.

           c) Certified copies of the resolutions of the Board of Directors of
         the Guarantor authorizing this Amendment and of all documents
         evidencing other necessary corporate action and governmental and
         regulatory approvals required to be obtained by it in connection
         therewith, certified by the Secretary or Assistant Secretary of the
         Guarantor.

           d) A favorable opinion of counsel to the Borrower, to the effect set
         forth in Annex I to this Amendment and as to such other matters
         relating to the transactions contemplated hereby as any Bank through
         the Agent may reasonably request.

           e) A favorable opinion of the General Counsel of the Guarantor, to
         the effect set forth in Annex II to this Amendment and as to such
         other matters relating to the transactions contemplated hereby as any
         Bank through the Agent may reasonably request.

           f) Evidence that the Guarantor has extended, through the Termination
         Date as extended hereby, the Guarantee set forth in Section 6.02 of
         the Existing Agreement.

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       g) Evidence that the "Expiration Date" of the Heat Purchase Contract has
     been extended to August 28, 1997 and that the "Outside Expiration Date" of
     the Heat Purchase Contract has been extended to September 1, 2000.

       h) Such other instruments, opinions or documents as any Bank through the
     Agent may reasonably request.

     SECTION 2.  Representations and Warranties.  EACH OF THE BORROWER AND THE
GUARANTOR REPRESENTS AND WARRANTS, AS TO ITSELF ONLY, AS FOLLOWS:


        (1) THE EXECUTION AND DELIVERY BY IT OF THIS AMENDMENT, AND THE
       PERFORMANCE BY IT OF THE AMENDED CREDIT AGREEMENT AND THE OTHER
       FINANCING DOCUMENTS TO WHICH IT IS A PARTY ARE WITHIN ITS CORPORATE
       POWERS, HAVE BEEN DULY AUTHORIZED BY ALL NECESSARY CORPORATE OR OTHER
       SIMILAR ACTION, AND DO NOT AND WILL NOT CONTRAVENE (1) ITS CHARTER OR
       BY-LAWS, AS THE CASE MAY BE, OR ANY LAW OR LEGAL RESTRICTION OR (1) ANY
       CONTRACTUAL RESTRICTION BINDING ON OR AFFECTING IT OR ITS PROPERTIES;

      a) This Amendment has been duly executed and delivered by it, and,
   assuming the due execution and delivery by the Banks pursuant to due
   authority of this Amendment, this Amendment, the Amended Credit Agreement
   and the other Financing Documents to which it is a party are its legal,
   valid and binding obligations, enforceable against it in accordance with
   their respective terms; subject to the effect of any applicable bankruptcy,
   insolvency, reorganization, moratorium or similar laws affecting creditors'
   rights generally;

      b) No consent, license, order, authorization or approval or other action
   by, and no notice to or filing with, any governmental authority or
   regulatory body is required for the due execution and delivery by it of this
   Amendment;

      c) Its representations and warranties contained in Section 4.01 (in the
   case of the Borrower) or Section 4.02 (in the case of the Guarantor) of the
   Existing Credit Agreement are true and correct in all material respects on
   and as of the date of this Amendment, as though made on and as of such date;

      d) No event in respect of it has occurred and is continuing, which
   constitutes an Event of Default or a Default; and

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         (a) In the case of the Guarantor: (a) the FERC Authorization is in full
       force and effect, (a) although scheduled by its terms to expire on
       December 31, 1996, the Guarantor intends to seek extension of the FERC
       Authorization and (a) without regard to any extension thereof, the FERC
       Authorization as presently in effect is sufficient to authorize: (a) the
       creation, validity and performance of the Guarantee described in Section
       6.01 of the Amended Credit Agreement in respect of each Advance made on
       or prior to December 31, 1996 or any later date to which the FERC
       Authorization may be extended, (a) the Guarantor to perform its
       obligations under the Credit Agreement and the other Financing Documents
       in respect of each such Advance and the corresponding Guarantee, and (a)
       the Guarantor to extend through the Termination Date as extended hereby
       the Guarantee set forth in Section 6.02 of the Credit Agreement and to
       perform its obligations thereunder.

        SECTION e)  REFERENCE TO AND EFFECT ON THE LOAN DOCUMENTS.  e) Upon the
   effectiveness of this Amendment in accordance with Section 2 hereof, on and
   after the date hereof each reference in the Credit Agreement to "this
   Agreement", "hereunder", "hereof" or words of like import referring to the
   Existing Credit Agreement, and each reference in the Notes and the other
   Financing Documents to "the Credit Agreement", "thereunder", "thereof" or
   words of like import referring to the Existing Credit Agreement, shall mean
   and be a reference to the Amended Credit Agreement.

        f) Except as specifically amended above, the Credit Agreement and all
   other Financing Documents are and shall continue to be in full force and
   effect and are hereby in all respects ratified and confirmed.

        g) The execution, delivery and effectiveness of this Amendment shall
not, except as expressly provided herein, operate as a waiver of any right,
power or remedy of any Bank or the Agent under any of the Financing Documents,
nor constitute a waiver of any provision of any of the Financing Documents.

        SECTION 3.  Costs and Expenses.  THE BORROWER AGREES TO PAY ON DEMAND
ALL REASONABLE COSTS AND EXPENSES OF THE AGENT IN CONNECTION WITH THE
PREPARATION, EXECUTION, DELIVERY, ADMINISTRATION, MODIFICATION AND AMENDMENT OF
THIS AMENDMENT AND THE OTHER INSTRUMENTS AND DOCUMENTS TO BE DELIVERED
HEREUNDER, INCLUDING,

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WITHOUT LIMITATION, THE REASONABLE FEES AND OUT-OF-POCKET EXPENSES OF COUNSEL
FOR THE AGENT WITH RESPECT THERETO AND WITH RESPECT TO ADVISING THE AGENT AND
THE BANKS AS TO THEIR RESPECTIVE RIGHTS AND RESPONSIBILITIES HEREUNDER AND
THEREUNDER.


     SECTION 4.  Execution in Counterparts.  THIS AMENDMENT MAY BE EXECUTED IN
ANY NUMBER OF COUNTERPARTS AND BY DIFFERENT PARTIES HERETO IN SEPARATE
COUNTERPARTS, EACH OF WHICH WHEN SO EXECUTED AND DELIVERED SHALL BE DEEMED TO
BE AN ORIGINAL AND ALL OF WHICH TAKEN TOGETHER SHALL CONSTITUTE BUT ONE AND THE
SAME AGREEMENT.


     SECTION 5.  Governing Law.  THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their respective officers thereunto duly authorized, as of the date
first above written,

                                                     RENAISSANCE ENERGY COMPANY



                                                     By
                                                       Title:


                                                     THE DETROIT EDISON COMPANY,
                                                      as Guarantor



                                                     By
                                                       Title:


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                                                                         ANNEX I

                 [SCOPE OF OPINION OF COUNSEL TO THE BORROWER]

The Opinion of Counsel to the Borrower referred to in Section 2(d) of this
Amendment shall re-affirm, as of the date of this Amendment, the opinions
expressed in the opinion of such counsel previously delivered pursuant to
Section 3.01(m) of the Existing Credit Agreement, except that, for purposes of
such re-affirmation, (i) the "Transaction Documents" shall be stated to include
this Amendment and (ii) references in such opinions to the "Credit Agreement"
shall be stated to refer to the Amended Credit Agreement.

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                                                                        ANNEX II

                 [SCOPE OF OPINION OF COUNSEL TO THE GUARANTOR]

The Opinion of Counsel to the Guarantor referred to in Section 2(e) of this
Amendment shall be to the effect that:

       (1) THE EXECUTION AND DELIVERY BY THE GUARANTOR OF THIS AMENDMENT, AND
       THE PERFORMANCE BY THE GUARANTOR OF THE AMENDED CREDIT AGREEMENT AND THE
       OTHER FINANCING DOCUMENTS TO WHICH IT IS A PARTY ARE WITHIN ITS CORPORATE
       POWERS, HAVE BEEN DULY AUTHORIZED BY ALL NECESSARY CORPORATE OR OTHER
       SIMILAR ACTION, AND DO NOT AND WILL NOT CONTRAVENE (1) ITS CHARTER OR
       BY-LAWS, AS THE CASE MAY BE, OR ANY LAW OR LEGAL RESTRICTION OR (1)  ANY
       CONTRACTUAL RESTRICTION BINDING ON OR AFFECTING IT OR ITS PROPERTIES;

         a) This Amendment has been duly executed and delivered by it, and,
   assuming the due execution and delivery by the Banks pursuant to due
   authority of this Amendment, this Amendment, the Amended Credit Agreement
   and the other Financing Documents to which the Guarantor is a party are the
   Guarantor's legal, valid and binding obligations, enforceable against the
   Guarantor in accordance with their respective terms; subject to the effect
   of any applicable bankruptcy, insolvency, reorganization, moratorium or
   similar laws affecting creditors' rights generally;

         b) No consent, license, order, authorization or approval or other
   action by, and no notice to or filing with, any governmental authority or
   regulatory body is required for the due execution and delivery by the
   Guarantor of this Amendment;

        (a)  (a) the FERC Authorization is in full force and effect, and without
    regard to any extension thereof, the FERC Authorization as presently in
    effect is sufficient to authorize: (a) the creation, validity and
    performance of the Guarantee described in Section 6.01 of the Amended Credit
    Agreement in respect of each Advance made on or prior to December 31, 1996
    or any later date to which the FERC Authorization may be extended,(a) the
    Guarantor to perform its obligations under the Credit Agreement and the
    other Financing Documents in respect of each such Advance and the
    corresponding Guarantee, and (a) the Guarantor to extend through the
    Termination Date as extended by this Amendment the Guarantee set forth in
    Section 6.02 of the Credit Agreement and to perform its obligations
    thereunder;

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AND such opinion of counsel to the Guarantor shall re-affirm, as of the date of
this Amendment, the opinions expressed in paragraphs 1, 4, 5 and 6 of the
opinion of such counsel previously delivered pursuant to Section 3.01(n) of the
Existing Credit Agreement.