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                                                                   Exhibit 10.22

                                             H Power/ADL Joint Venture Agreement

                             Joint Venture Agreement

      THIS AGREEMENT (this "Agreement") is made as of December 18, 1998, between
H Power Corp., a Delaware corporation having its principal place of business at
60 Montgomery Street, Belleville NJ 07109, (hereinafter referred to as "H
Power") and Arthur D. Little, Inc. having executive offices at Acorn Park,
Cambridge, Massachusetts 02140 (hereinafter referred to as "ADL").

      Throughout this Agreement, H Power and ADL may be referred to collectively
as the "Parties" and each individually as a "Party".

      WHEREAS, H Power has acquired, developed, possesses and owns specialized,
novel, and unique techniques, inventions, practices, methodologies, knowledge,
skill, experience, data, formulae, computer programs and other information
relating to the design and manufacture of proton exchange membrane ("PEM") fuel
cells and to the design and manufacture of complete fuel cell operating systems,
including but not limited to hydrogen supply and delivery sub-systems,
temperature and water management sub-systems, control sub-system, and power
conditioning sub- systems, some of which have been reduced to patents, pending
patent applications or disclosure documents and others of which are deemed to be
proprietary know-how (all of which are hereinafter referred to as H Power's
Intellectual Property); and

      WHEREAS, H Power has utilized and is continuing to utilize its
Intellectual Property to design, develop, integrate, assemble and produce fuel
cell operating systems to replace or supplement conventional power sources such
as batteries, diesel generators, internal combustion engines and central power
stations, in a broad base of products and for various applications; and

      WHEREAS, ADL is a company specializing in areas ranging from product
development and technology assessment to process engineering and manufacturing
consulting; and

      WHEREAS, ADL has developed expertise in fuel processors operating on a
variety of fuels, and

      WHEREAS, the Parties desire to collaborate under the terms of this
Agreement to jointly study, design, develop, fabricate and demonstrate a
commercially viable System that incorporates a PEM fuel cell sub-system and a
propane fuel processor sub-system which supplies the hydrogen fuel to the PEM
sub-system; and


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                                             H Power/ADL Joint Venture Agreement


      WHEREAS, the Parties believe that such Systems will meet the needs of
telecommunications systems for premium power and will establish a technology
base from which various other products will be created; and

      WHEREAS, the Parties have been selected for participation in the Advanced
Technology program administered by tho National Institute of Standards and
Technology as a joint venture to conduct certain specified research and
development, and

      WHEREAS, the Parties wish to enter into a joint venture agreement to
define their respective roles and responsibilities; and

      WHEREAS, the Parties have selected H Power to serve as the Administrator
for the joint venture and wish to authorize, that organization to perform
certain functions, specifically including executing the NIST Cooperative
Agreement and thereby binding all the Parties to the terms and conditions of
that agreement;

      NOW THEREFORE, in consideration of the foregoing recitals and the terms,
conditions and covenants contained herein, it is hereby agreed as follows:

1.    Definitions

      1.1   Administrator.

            Administrator shall mean H Power Corp. and/or its appointed
            representative.

      1.2   Agreement.

            Agreement shall mean this Joint Venture Agreement, as the same may
            be amended from time to time hereafter.

      1.3   Background Technology.

            Background Technology shall mean technical information not generated
            in the course of the NIST Program.

      1.4   Government Use License.

            Government Use License shall mean a nonexclusive, nontransferable,
            irrevocable, paid-up license to practice or have practiced by or on
            behalf of the United States throughout the world any Subject
            Invention.

      1.5   NIST.

            NIST shall mean the National Institute of Standards and Technology.


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                                             H Power/ADL Joint Venture Agreement


      1.6   NIST Cooperative Agreement.

            NIST Cooperative Agreement shall mean the funding agreement entered
            into between the Advanced Technology Program of NIST and the Parties
            hereto (as executed by the Administrator) for the conduct of the
            Research Program.

      1.7   Patents.

            Patents shall mean all patents and applications relating thereto
            resulting from Subject Inventions.

      1.8   Program or Research Program.

            Program or Research Program shall mean the research and development
            program set forth in the Proposal and included herein as Exhibit A.

      1.9   Proposal.

            Proposal shall mean the proposal submitted by the Parties to the
            Advanced Technology Program, and which has been accepted by NIST for
            funding.

      1.10  Statement of Work.

            Statement of Work shall mean the performance of activities as
            specifically set forth in Section 1.3 (entitled "Technical
            Approach") of the Proposal.

      1.11  Subject Invention.

            Subject Invention shall mean any invention conceived or first
            reduced to practice in the course of the Program.

      1.12  System.

            System shall mean a PEM fuel cell sub-system integrated with a
            propane fuel processor sub-system that will be utilized in
            telecommunication applications.

      1.13  Technology.

            Technology shall mean all technical information generated in the
            course of the Program.

2.    Purpose of this Joint Venture

      The limited purpose and the sole business of this Joint Venture shall be
      to accomplish the objectives of the Program by performing research
      directly and through the use of contracts, and to that end shall carry out
      their responsibilities as set forth in the Program, the NIST Cooperative
      Agreement, and the Statement of Work. The Joint Venture may engage in such
      other activities related either directly or indirectly to the foregoing as
      may be necessary


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                                             H Power/ADL Joint Venture Agreement


      advisable or convenient to the promotion or conduct of the Parties'
      businesses, but no other business shall be conducted by the Joint Venture
      without the prior written consent of both of the Parties hereto.

3.    Term of this Joint Venture

      The term of the Joint Venture shall commence on and as at the date of this
      Agreement and shall continue until the Parties' obligations as set forth
      in this Agreement and the NIST Cooperative Agreement have been completed,
      or until the NIST Cooperative Agreement has been terminated. An individual
      Party may cease participation in the Program only in a manner consistent
      with the NIST Cooperative Agreement.

4.    Obligation of the Parties

      4.1   Activities

            The Parties shall use their best efforts to carry out the purposes
            of this Agreement, as set forth in Paragraph 2, hereinabove.

      4.2   Contributions

            Each of the Parties agrees to contribute funds or in kind services
            as follows:

                                Year One          Year Two            Total
                               ----------         --------            -----
            H Power            $  548,555         $933,628         $1,482,183
            ADL                $1,092,544         $642,722         $1,735,266

      4.3   Responsibilities Of Each Of The Parties

            The primary responsibilities of the Parties to this Agreement shall
            be as follows:

                  H Power:    H Power shall be responsible for the design,
                              development, fabrication and testing of the fuel
                              cell sub-system, the integration of the System and
                              the testing of the completed System.

                  ADL:        ADL shall be responsible for the design,
                              development, fabrication and testing of the
                              propane fuel processor sub-system.

      4.4   Cooperation Between Parties

            The Parties shall cooperate fully with each other with respect to
            their primary responsibilities.


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                                             H Power/ADL Joint Venture Agreement


      4.5   Execution of Work

            4.5.1 H Power shall design, develop, fabricate and test its PEM fuel
                  cell sub-system in its facilities at Belleville, NJ

            4.5.2 ADL shall design, develop, fabricate and test its propane fuel
                  processor subsystem in its facilities.

            4.5.3 H Power shall integrate, assemble and test completed System at
                  its place of business in Belleville, NJ.

5.    Program Management

      To promote consultation and cooperation among the Parties hereto a
      committee shall be formed as follows:

      5.1   A Joint Management Committee which shall consist of four
            representatives of H Power and three representatives of ADL and
            which will ordinarily meet once each month. Such meetings will be
            held at the premises of H Power in Belleville, NJ, unless otherwise
            agreed by the Parties hereto. The Chairman at the meetings of the
            Joint Committee shall be the Chief Executive Officer of H Power.

      5.2   At such meetings the Joint Management Committee shall consider and
            advise upon and make recommendations to the Parties hereto on
            matters of policy pertaining to prospective and actual cooperation
            among the Parties hereto in the performance of this Agreement.

      5.3   The representatives of the Parties shall be nominated by each of the
            Parties hereto by notice in writing to the other Party hereto. A
            Party, at anytime, may replace any and all of its said
            representatives by such notice.

      5.4   The Joint Management Committee shall direct the conduct of the
            Program in all respects, through the Administrator.

      5.5   The Administrator, who shall perform the day-to-day management and
            administration of the Program in accordance with all legal and
            regulatory requirements, including the NIST Cooperative Agreement,
            shall be an H Power member of the Joint Management Committee.

6.    Intellectual Property Rights

      6.1   In accordance with the Advanced Technology Program (ATP) statute and
            regulation, specifically 15 USC 278n(d)(11)(A) and 15 CFR
            295.8(a)(1), title to inventions arising from assistance by the
            Program will vest in H Power and ADL. Title to any such intellectual
            property shall not be transferred or passed, except to a company
            incorporated in the United States, until the expiration of the first
            patent obtained in connection with the intellectual property.
            Nothing in this paragraph shall be construed to prohibit the
            licensing to any company of intellectual property rights arising
            from assistance provided by this Program.


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                                             H Power/ADL Joint Venture Agreement


      6.2   The United States may reserve a non-exclusive, nontransferable,
            irrevocable paid-up license to practice or have practiced for, and
            on behalf of the United States any such intellectual property, but
            shall not, in the exercise of such license, publicly disclose
            proprietary information related to the license.

      6.3   Subject to sub-paragraphs 6.1 and 6.2, all intellectual property
            rights relating to the PEM fuel cell sub-system shall become sole
            and exclusive property of H Power and all intellectual property
            rights relating to the propane fuel processor sub-system shall
            become sole and exclusive property of ADL.

7.    Confidentiality

      Each of the Parties agrees that the Background Technology, the
      intellectual property rights generated during the course of the Program
      and the Proprietary Information of the other Party shall be covered by the
      Bilateral Confidentiality Agreement executed by ADL, on January 30, 1996
      and by H Power on February 2, 1996. The Parties hereto further agree to
      extend the term of that agreement from three years from the last date of
      its execution to three years from the expiration of this Joint Venture
      Agreement. A copy of said Confidentiality Agreement is attached hereto as
      Exhibit B.

8.    Disputes

      8.1   Any question, dispute or difference arising among the Parties hereto
            and in particular, any matter which may affect their respective
            obligations or liabilities to each other or any third party, shall
            be resolved within the Joint Management Committee referred to in
            Paragraph 5 hereinabove.

      8.2   If in the event that these discussions fail to reach a mutually
            acceptable conclusion within a reasonable period of time, then the
            question, dispute, difference or matter shall be referred to the
            respective Managing Directors/Chief Executive Officers of the
            Parties hereto, or to such Directors as may be appointed to act on
            their behalf, which Directors shall then be responsible for
            considering and reaching a mutually acceptable decision on said
            question, dispute, difference or matter.

      8.3   No Party shall discontinue its efforts in pursuance of this
            Agreement while any question, dispute, difference or matter is under
            consideration by the Managing Directors/Chief Executive Officers of
            the Parties hereto or during arbitration proceedings as provided
            under this Clause.

      8.4   If in the event that a decision cannot be mutually agreed then the
            question, dispute, difference or matter shall be determined by
            arbitration, in the city of Newark, New Jersey in accordance with
            the Commercial Arbitration Rules of the American Arbitration
            Association.


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                                             H Power/ADL Joint Venture Agreement


9.    Insurance

      Each Party shall obtain and maintain appropriate public liability and
      casualty insurance, or adequate levels of self insurance, to insure
      against any liability caused by that Party's obligations under this
      Agreement and the NIST Cooperative Agreement.

10.   Termination

      Subject to the requirements of the NIST Cooperative Agreement, this
      Agreement may be terminated by either Party upon sixty (60) days written
      notice if the other Party hereto becomes controlled by any other company
      or entity that is in direct competition with any of the other Parties.

11.   Force Majeure

      In the event that a Party is prevented or delayed from performing,
      fulfilling or completing an obligation provided for in this Agreement as a
      result of delays caused by strikes, lock-outs, unavailability of
      materials, acts of God, acts of any national, state or local governmental
      agency or authority or a foreign government, war, insurrection, rebellion,
      riot, civil disorder, fire, explosion or the elements, provided that such
      prevention or delay is not caused or due to any act or omission or
      negligence of the Party claiming Force Majeure, then the time for
      performance, fulfillment or completion shall be extended for a period not
      exceeding the number of days by which the same was so delayed.

12.   Costs and Expenses

      Each Party shall bear its own costs and other related expenses incurred in
      the performance of this Agreement and neither Party shall be liable for
      any costs, expense, risk, obligation or liability related to or arising
      out of the other's efforts and responsibilities under this Agreement.

13.   Consequential Damages

      Except as may be specifically provided for herein, neither Party shall be
      liable to the other Party under this Agreement for any indirect,
      incidental, special or consequential damages, however caused, whether in
      contract, tort, strict liability, warranty or otherwise.

14.   Limited Purpose Joint Venture

      Nothing in this Agreement shall be deemed to constitute, create, give
      effect to, or otherwise any type of permanent arrangement of any kind, and
      the rights and obligations of the Parties hereto shall be limited to those
      expressly set forth herein. Nothing herein shall be construed as providing
      the sharing of profits or losses arising out of the efforts of any one of
      the Parties except as may be provided for in any resultant sub-contract
      agreed among the Parties. The cooperation of the Parties is for the
      purpose of complementing their respective capabilities.


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                                             H Power/ADL Joint Venture Agreement


15.   Notice

      All notices, requests, demands or other communications which are required
      or may be given pursuant to the terms of this Agreement should be in
      writing and delivery shall be effective in all respects if delivered: (i)
      by telefax and promptly confirmed by letter, (ii) personally, or (iii) by
      registered or certified mail, postage prepaid, (or if overseas by postage
      paid registered [if available] international air mail) as follows:

            If to H Power                       If to ADL
            -------------                       ---------
            60 Montgomery Street                25 Acorn Park
            Belleville, NJ 07109                Cambridge, MA 02140
            U.S.A.                              U.S.A.
            Telefax (973) 450-9850              Telefax (617) 498-7117
            Attention CEO                       Attention General Counsel

      Proof of transmission in the case of telefax shall be deemed to be proof
      of receipt on the date and at the time of dispatch subject to a confirmed
      answer back at the end of the transmission.

      Notices hereunder shall be deemed to have been received by the receiving
      Party if sent by telefax upon proof of receipt on the date and at the time
      of dispatch as set out above, if delivered personally at time of receipt
      and if sent by mail five working days after the notice mailed, as the case
      may be, unless otherwise proved by the Party claiming non-receipt.

16.   Scope

      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,
      and neither of the Parties shall be bound by any definition, condition,
      representation, warranty, promise or provision other than is expressly set
      forth in this Agreement.

17.   Modification

      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.

18.   Severability

      In the event any of the provisions of this Agreement, for any reason,
      shall be declared invalid, such decision shall not affect the validity of
      the remaining portion, which shall remain in full force and effect. The
      Parties hereto agree to negotiate a substitution for the provisions held
      invalid, illegal or unenforceable.


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                                             H Power/ADL Joint Venture Agreement


19.   Effect of Waivers

      Failure of either Party hereto to insist upon strict compliance with any
      of the terms, covenants and conditions hereof shall not be deemed waiver
      or relinquishment of any similar right or power hereunder at any
      subsequent time or of any other provision hereof.

20.   Governing Law and Venue

      The validity, performance, construction, and effect of this Agreement will
      be governed by the law of the State of New Jersey.

21.   Binding Effect

      This Agreement shall be binding upon the Parties hereto and their
      respective executors, administrators, heirs, assigns and successors in
      interest.

22.   Survival of Contents

      Notwithstanding anything else in this Agreement to the contrary, those
      provisions of this Agreement which by their nature survive the termination
      or expiration of this Agreement shall do so to the extent required thereby
      for the full observation and performance by any or all of the Parties
      hereto.

23.   Assignment

      Neither Party hereto may sell, assign, transfer or hypothecate any rights
      or interests created under this Agreement or delegate any of its duties
      without the prior written consent of the other. Any such assignment or
      delegation of either Party hereunder without such consent shall be void.
      Notwithstanding the foregoing, H Power, in its sole discretion, shall have
      the right to assign this Agreement to an affiliate of H Power.
      Notwithstanding the foregoing, ADL, in its sole discretion, shall have the
      right to assign this Agreement to Epyx or any affiliate of ADL.

24.   Indemnity

      Each Party shall be responsible for any and all losses or damages arising
      out of or incurred as a result of its own negligence. Each agrees to
      indemnify and hold the other harmless from and with respect to any such
      loss or damage including, without limitation, attorney's fees and costs.

25.   No Broker or Finder

      The Parties acknowledge that in negotiating and entering into this
      Agreement, they have not been represented or assisted by any broker or
      finder who may be entitled to compensation.


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                                             H Power/ADL Joint Venture Agreement


26.   Attorney's Fees

      If any legal action or any arbitration or other proceeding is brought for
      the enforcement of this Agreement or because of an alleged dispute, breach
      or default in connection with any of the provisions of this Agreement, the
      successful or prevailing Party shall be entitled to recover reasonable
      attorneys' fees incurred in this action or proceeding in addition to any
      other relief to which he or it may be entitled.

27.   Power of Attorney

      By signing this Agreement, ADL grants to the Administrator a Power of
      Attorney for the sole purpose of binding ADL to the terms and conditions
      of the NIST Cooperative Agreement.

28.   NIST Cooperative Agreement Precedence

      Should there be any conflict between the terms and conditions of this
      Agreement and the NIST Cooperative Agreement, the NIST Cooperative
      Agreement shall take precedence.

29.   Construction

      The Recitals to this Agreement and all Exhibits, Schedules and Riders
      executed by the Parties and attached hereto shall be deemed a part of this
      Agreement. Any table of contents accompanying this Agreement and any
      heading contained herein are for directory purposes only, do not
      constitute a part of this Agreement, and shall not be employed in
      interpreting this Agreement. Whenever the singular number is used in this
      Agreement and when required by the context, the same shall include the
      plural, and the masculine gender shall include the feminine and neuter
      genders.

30.   Index and Captions

      The captions of the Clauses of this Agreement are solely for convenient
      reference and shall not be deemed to affect the meaning or interpretation
      of any paragraph hereof.

31.   Cooperation Between the Parties

      In entering into this Agreement the Parties hereto recognize that it is
      impractical to make provision for every contingency that may arise in the
      course of the observance or performance thereof. Accordingly the Parties
      hereby declare it to be a cardinal principle of this Agreement and it to
      be their common intention that this Agreement shall operate between them
      with fairness and without detriment to the interests of any of them and if
      in the course of the performance of this Agreement unfairness to a Party
      hereto is disclosed or anticipated then the Parties hereto shall use their
      best endeavors to agree upon such action as may be necessary and equitable
      to remove the cause or causes of the same.


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                                             H Power/ADL Joint Venture Agreement


32.   Additional Documentation

      Upon the request of either Party, each Party shall execute and deliver
      instruments, agreements, certificates and other documents as may be
      reasonably required in order to implement any of the terms or provisions
      of this Agreement.

33.   Counterparts

      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.

34.   Officers of the Parties

      All the persons executing this Agreement are duly authorized officers of
      the Parties hereto and execute this Agreement in accordance with the
      authority vested in them by the by-laws and Board of Directors of their
      respective corporations.

IN WITNESS WHEREOF, the Parties hereto have executed this Agreement.

For H POWER CORP.                         For ARTHUR D. LITTLE, INC


Signed: /s/ Arthur Kaufman                Signed: /s/ Jeffrey M. Bentley
        -------------------------------           ------------------------------

Title:  Vice President                    Title:  Vice - President
        -------------------------------           ------------------------------

Date:   Dec. 21, 1998                     Date:   12/18/98
        -------------------------------           ------------------------------


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