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                                                  Exhibit 10.20.4

                            AGREEMENT

                             BETWEEN

                  O'BRIEN ENERGY SYSTEMS, INC.

                               AND

              E. I. DU PONT DE NEMOURS AND COMPANY

           AMENDMENT NO. 3 TO STEAM PURCHASE CONTRACT


          O'Brien  Energy Systems, Inc. ("O'Brien") and E. I. du
Pont de Nemours and Company ("DuPont") entered into a Steam
Purchase Contract dated December 8, 1986, as amended  by
Amendment No. 1 to Steam Purchase Contract dated January 12,
1988, and by a letter agreement dated July 25, 1988 (Amendment
2), pursuant to which O'Brien has agreed to supply steam to
DuPont's Parlin, New Jersey plant, from a cogeneration facility
which O'Brien will build on land leased from Du Pont.  Du Pont
and O'Brien now desire to amend further that Contract.
Therefore, in consideration of the mutual covenants contained
herein, the sufficiency of which is acknowledged by both parties,
DuPont and O'Brien hereby agree that the Steam Purchase Contract
of December 8, 1986, as previously amended, is further amended as
follows:

          1.   The sentence in Article 4(A) beginning "O'Brien
represents that." is modified to read as follows:

               O'Brien represents that the Initial Delivery Date
          shall be on or before August 31, 1990, provided that
          the Initial Delivery Date shall be extended by the
          occurrence and continuation of an event of Force
          Majeure as defined in Article 7 below.

          2.   The sentence in Article 4(A) beginning "In lieu of
accepting these." is modified to read as follows:

               In lieu of accepting these liquidated damages, or
          in the event that O'Brien should fail to pay them,
          DuPont shall have the right topursue all available
          remedies at law or in equity, provided, however, that
          in the event construction of the Facility has begun
          prior to August 31, 1989 and O'Brien can demonstrate a
          program of continuous construction that is at least 75
          percent complete by August 31, 1990, unless excused by
          Force Majeure, DuPont agrees not to exercise any remedy
          which could result in termination of this Agreement
          prior to February 1, 1992.

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          3.   Four new Sections are added to Article 9.  The
current paragraph in Article 9 beginning "DuPont will supply
1,000 gallons." shall be designated Section A and three new
Sections to be added shall be designated Sections B, C, D and E.
They shall read as follows:

               B.   Du Pont agrees, subject to DuPont's
          determination that it has available adequate capacity
          to do so, to permit O'Brien to interconnect the
          Facilitie's waste water disposal system with DuPont's
          existing sanitary sewer system.  The discharges from
          the Facility are estimated to be an average flow of 120
          gallons per minute.  O'Brien agrees to construct the
          necessary interconnection and shall install monitoring
          as required by the Middlesex County Utilities
          Authority.  O'Brien further agrees to indemnify DuPot
          in accordance with Article 16 of this Agreement should
          such indemnity be required in connection with waste
          generated by O'Brien into the sanitary sewer system.
          If O'Brien connects to DuPont's sanitary sewer system,
          it agrees to pay its proportionate share of any
          maintenance costs or costs related to blockage repair
          on that portion of the sewer sanitary system being
          utilized by O'Brien, such costs to be computed by
          determining the pro-rata usage by DuPont and O'Brien
          for that shared portion.

               C.   Du Pont agrees to permit O'Brien to provide a
          storm water detention basin and connect into the
          existing plant storm sewer piping system, so that rain
          water maybe discharged from the site.

               D.   Du Pont agrees to provide temporary parking
          and access to the O'Brien site during construction and
          operation of the Facility until such time as a proposed
          traffic light at the intersection of Washington Road,
          Lakeview Drive, and the O'Brien entrance is
          operational.

               E.   DuPont agrees, subject to Du Pont's
          determination that it has available adequate capacity
          to do so, to permit O'Brien, at O'Brien's option, to
          provide a new supply line from the fire pump house to
          the Facility and to connect the Facility with DuPont's
          fire protection water supply system for the purpose of
          designing and developing a fire protection system for
          the Facility.  If O'Brien exercises this option,
          O'Brien will be responsible

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          at it expense for maintaining, repairing and, if
          necessary, upgrading that portion of the fire
          protection water supply system beginning at the
          existing DuPont fire pump station (including the fire
          lake reservoir) and ending at the Facility.  DuPont
          shall have the right to do this work itself, but at
          O'Brien's expense.  DuPont agrees not to repair or
          alter its fire protection water supply system in a
          manner which would deprive O'Brien of a sufficient
          water supply for its fire protection system without the
          consent of O'Brien.  O'Brien further agrees to
          indemnify DuPont in accordance with Article 16 of this
          Agreement should such indemnity be required in
          connection with a failure of DuPont's fire protection
          water supply system to put out a fire at the Facility.
          If O'Brien connects the Facility to DuPont's fire
          protection water supply system, it agrees to pay its
          proportionate share of any repair costs due to a
          failure of the fire protection water supply system on
          that portion of the fire protection water supply system
          being utilized by O'Brien, such costs to be computed on
          a pro-rata basis with reference to the percentage of
          square footage comprising buildings at O'Brien's
          Facility as compared to square footage comprising
          buildings owned or occupied by duPont at the Parlin
          site.  O'Brien further agrees to design the Facility
          fire protection system via a fire "loop" which will tie
          into the DuPont fire protection water supply system at
          both connection points at the outer boundaries of the
          leased premises and which will eliminate the existing
          DuPont fire protection water supply system piping on
          the leased premises.

          4.   The sentence in Article 12(D) beginning "If DuPont
elects to close down." is modified to read as follows:

               If DuPont elects to close down or abandon the
          Parlin operations or site, its obligations under this
          Agreement shall terminate except for (1) the lease of
          the Facility site and the adjoining land described in
          the Ground Lease to O'Brien, (2) the provision of
          continued access to the Facility Site and adjoining
          plot, (3) provision of the water supply pursuant to
          this agreement assuming that DuPont is still operating
          its water treatment plant, (4) the allocation of
          responsibility for environmental contamination set
          forth in Article 8(D) of this Agreement, and (5) the
          provisions

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          regarding the rebuilding of the Facility set forth in
          Article 17(B) of this Agreement.

          5.   A new Section is added to Article 17.  The current
paragraph in Article 17 beginning "At all times during." shall be
designated Section A and the new Section shall be designated
Section B.  Section B to Article 17 shall read as follows:

               B.   Notwithstanding anything contained in this
          Agreement or in Section 17 of the Ground Lease between
          O'Brien and DuPont, dated January 2, 1987, in the event
          that any part of the Facility shall be destroyed or
          damaged in whole or in part by fire or other cause
          covered within the extended coverage of the fire
          insurance policies carried by O'Brien, O'Brien may, but
          shall not be required to repair, replace or rebuild any
          such portion of the Facility except as is hereinafter
          provided.  If the back-up boiler and all necessary
          auxiliaries or both heat recovery boilers or any such
          greater part of the Facility including, either or both
          of the back-up boiler and all necessary auxiliaries and
          both heat recovery boilers, shall be destroyed or
          damaged in whole or in part by fire or other causes
          within the extended coverage of the fire insurance
          policies carried by O'Brien, in such event, if DuPont
          continues to require steam in accordance with the terms
          of this Agreement, O'Brien agrees to dedicate such
          portion of the insurance proceeds paid under applicable
          policies as may be necessary to repair or replace or
          rebuild the back-up boiler, one of the heat recovery
          boilers and the electrical interconnection facilities
          necessary to supply electricity to DuPont.

               In addition, in the event that the Facility is not
          replaced following destruction thereof by fire or other
          cause covered within the extended coverage of the fire
          insurance policy carried by O'Brien, insurance proceeds
          sufficient to pay for the cost of demolition, removal
          of equipment from site (excluding  foundation) and
          restoration to a safe condition will be dedicated by
          O'Brien for such purposes.

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As amended by this Amendment 3, the Steam Purchase Contract as
earlier amended, remains in full force and effect.

               O'BRIEN ENERGY SYSTEMS, INC.

               BY: /s/ Sanders Newman

               Title: Senior V.P. Secretary & General Counsel

               Date: 12/14/88


               E. I. DU PONT DE NEMOURS AND COMPANY

               BY: /s/ George R. Carson

               Title: Sr. Purchasing Agent

               Date: 12/12/88

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