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                                                                   Exhibit 10.28

                                    AGREEMENT

      This Agreement is made on this 20th day of August 1999, between H Power
Enterprises of Canada, Inc., a Canadian corporation ("HPEC"), and H Power Corp.,
a Delaware corporation, with its principal offices at 60 Montgomery Street,
Belleville, NJ 07109 ("H Power").

      Whereas, HPEC and H Power entered into a Technology Licensing Agreement
and a Stock Exchange Agreement, both dated May 2, 1997, setting forth terms and
conditions relating to HPEC's exclusive marketing rights; and

      Whereas, Section 3.2 of the Technology Licensing Agreement provides that
HPEC has exclusive rights to market, promote, advertise, sell, service,
distribute and merchandise (the "Exclusive Rights") certain stationary power
fuel cell technology (the "Fuel Cell Technology") in Canada, and at such time as
certain of HPEC's investors exercise their exchange rights under the Stock
Exchange Agreement, to Canada, North America and Central America; and

      Whereas, H Power has entered into a licensing agreement (the "Licensing
Agreement") with ECO Fuel Cells LLC, A Delaware limited liability company ("ECO
LLC") effective as of the date hereof; and

      Whereas, the arrangement with ECO LLC is twofold, being comprised of a
substantial equity investment in H Power and an exclusive distributorship to
market H Power's fuel cell stationary power systems within all the counties in
the United States presently served by ECO LLC's members; and

      Whereas, the terms of the Licensing Agreement conflict with HPEC's
Exclusive Rights under the Technology Licensing Agreement; and

      Whereas, HPEC has agreed to waive its exclusive rights under the
Technology Licensing Agreement and to cooperate with H Power to consummate the
Licensing Agreement.

      Now, Therefore, in consideration of these premises and other good and
valuable consideration, including the sum of $1.00 paid to HPEC by H Power, the
receipt of which is hereby acknowledged, the Parties hereby agree as follows:

1.    HPEC hereby relinquishes all of its Exclusive Rights to North America
      under the terms of the Technology Licensing Agreement, whether now in
      existence or in the future acquired upon the exercise of certain exchange
      rights under the Technology Licensing Agreement, but only to the extent
      that they infringe on the rights granted to ECO LLC by H Power under the
      Operating Agreement.

2.    This Agreement embodies all the understandings and agreements of the
      Parties and supersedes all prior and contemporaneous, oral or written
      agreements or understandings relating to the matters referred to herein.

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3.    This Agreement may be amended or modified only by an instrument of equal
      formality signed by duly authorized officers or representatives of the
      respective Parties hereto.

4.    The validity, performance, construction and effect of this Agreement will
      be governed by the law of the State of New Jersey. This Agreement shall be
      binding upon the Parties hereto and their respective executors,
      administrators, heirs, assigns and successors in interest.

5.    This Agreement may be executed in any number of counterparts, each of
      which shall be deemed to be an original, all of which shall constitute one
      and the same Agreement.

      IN WITNESS WHEREOF, H Power has caused this Agreement to be signed by its
corporate officer thereunto duly authorized, and HPEC by H. Frank Gibbard, its
President, as authorized by HPEC's Board of Directors at a meeting on July 27,
1999.


H POWER CORP.                             H POWER ENTERPRISES OF CANADA, INC.


By: /s/ H. Frank Gibbard                  By: /s/ H. Frank Gibbard
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Its:                                      Its:
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