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                                                                   EXHIBIT 99-20

                  SEVENTH AMENDMENT TO TRUST AGREEMENT BETWEEN
                      FIDELITY MANAGEMENT TRUST COMPANY AND
                           THE DETROIT EDISON COMPANY

      THIS SEVENTH AMENDMENT, dated as of the fifteenth day of December 1999, by
and between Fidelity Management Trust Company (the "Trustee") and The Detroit
Edison Company (the "Sponsor");

                                   WITNESSETH:

      WHEREAS, the Trustee and the Sponsor heretofore entered into a Trust
Agreement dated June 30, 1994, and amended February 5, 1995, June 30, 1994 and
August 1, 1996, with regard to The Detroit Edison Savings & Investment Plan, The
Detroit Edison Savings & Investment Plan for Employees Represented by Local 17
of the International Brotherhood of Electrical Workers, and The Detroit Edison
Savings & Investment Plan for Employees Represented by Local 223 of the Utility
Workers Union of America (collectively and individually, the "Plan"); and

      WHEREAS, the Trustee and the Sponsor now desire to amend said Trust
Agreement as provided for in Section 14 thereof;

      NOW THEREFORE, in consideration of the above premises the Trustee and the
Sponsor hereby amend the Trust Agreement by:

(1)   Amending Section 5(h) Trustee Powers, by inserting a new subsection (ix)
      as follows:

                  (ix) To borrow funds from a bank not affiliated with the
      Trustee in order to provide sufficient liquidity to process Plan
      transactions in a timely fashion; provided that the cost of such borrowing
      shall be reasonable and shall be allocated in a reasonable fashion to the
      investment fund(s) in need of liquidity.

(2)   Adding a new Section 15, Electronic Services, as follows, and renumbering
      all subsequent subsections accordingly:

      Section 15. Electronic Services.

      (a) The Trustee may provide communications and services via electronic
      medium ("Electronic Services"), including, but not limited to. Fidelity
      Plan Sponsor WebStation, Client Intranet, Client e-mail, interactive
      software products or any other information provided in an electronic
      format. The Sponsor, its agents and employees agree to keep confidential
      and not publish, copy, broadcast, retransmit, reproduce, commercially
      exploit or otherwise redisseminate the data, information, software or
      services without the Trustee's written consent.

      (b) The Sponsor shall be responsible for installing and maintaining all
      Electronic Services on its computer network and/or Intranet upon receipt
      in a manner so that the information provided via the Electronic Service
      will appear in the same form and content as it appears on the form of
      delivery, and for any programming required to accomplish the installation.
      Materials provided for Plan Sponsor's intranet web sites shall be
      installed by the Sponsor and


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      shall be clearly identified as originating from the Trustee. The Sponsor
      shall promptly remove Electronic Services from its computer network and/or
      Intranet, or replace the Electronic Service with an updated service
      provided by the Trustee, upon written notification (including written
      notification via facsimile) by the Trustee.

      (c) All Electronic Services shall be provided to the Sponsor without any
      express or implied legal warranties or acceptance of legal liability by
      the Trustee relative to the use of material or Electronic Services by the
      Sponsor. No rights are conveyed to any property, intellectual or tangible,
      associated with the contents of the Electronic Services and related
      material.

      (d) To the extent that any Electronic Services utilize Internet services
      to transport data or communications, the Trustee will take, and Plan
      Sponsor agrees to follow, reasonable security precautions; however, the
      Trustee disclaims any liability for interception of any such data or
      communications. The Trustee shall not be responsible for, and makes no
      warranties regarding access, speed or availability of Internet or network
      services. The Trustee shall not be responsible for any loss or damage
      related to or resulting from any changes or modifications to the
      electronic material after delivering it to the Plan Sponsor.

(3)   Amending Schedule "B" as follows:

      EFFECTIVE JANUARY 1, 2000, restating the "Annual Participant Fee" section,
      in its entirety, as follows:

      -     Annual Participant Fee: $0 per Participant.

      EFFECTIVE JANUARY 1, 2000, deleting the "Trustee Fees" section in its
      entirety.

      By restating the "Other Fees" bullet point, in its entirety, as follows:

      Other Fees: separate charges for optional non-discrimination testing,
      extraordinary expenses resulting from large numbers of simultaneous manual
      transactions, from errors not caused by Fidelity, reports not contemplated
      in this Agreement, corporate actions, or the provision of communications
      materials in hard copy which are also accessible to participants via
      electronic services in the event that the provision of such material in
      hard copy would result in an additional expense deemed to be material. The
      Administrator may withdraw reasonable administrative fees from the Trust
      by written direction to the Trustee,

      EFFECTIVE JANUARY 1, 2000, restating the "Note" section, in its entirety,
      as follows:

      Note: These fees have been negotiated and accepted based on the following
      Plan characteristics: current plan assets of S1028.0 million, current
      participation of 972 participants, current stock assets of S184 million,
      total Fidelity actively managed Mutual Fund assets of $ 677 0 million,
      total Fidelity non-actively managed Mutual Fund assets of $ 1180 million,
      total Non-Fidelity Mutual Fund assets of $ 49 million, and projected net
      cash flows of $18 million per year. Fees will be subject to revision if
      these Plan characteristics change significantly by either falling below or
      exceeding current or projected levels.

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      IN WITNESS WHEREOF, the Trustee and the Sponsor have caused this Seventh
Amendment to be executed by their duly authorized officers effective as of the
day and year first above written.

THE DETROIT EDISON COMPANY                   FIDELITY MANAGEMENT TRUST
                                             COMPANY

By: /s/ Anthony F. Earley   12-28-09         By: /s/ Carolyn Redden   01-28-2000
    ---------------------   --------             ------------------   ----------
    Anthony F. Earley JR.    Date                Carolyn Redden          Date
                                                 Vice President

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