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                                                                     Exhibit 4.1

                          REGISTRATION RIGHTS AGREEMENT

                                 March 25, 1996

To Duquesne Enterprises
Grant Building
Suite 2420
Pittsburgh, PA  15219

Gentlemen:

      This will confirm that in consideration of your agreement to purchase
certain shares (the "Preferred Shares") of Series A Convertible Preferred Stock,
$.001 par value per share ("Preferred Stock"), of H Power Corp., a Delaware
corporation (the "Company"), pursuant to the Securities Purchase Agreement dated
as of March ___, 1996 (the "Purchase Agreement") between the Company and you,
and as an inducement to you to consummate the transactions contemplated by the
Purchase Agreement, the Company covenants and agrees with you as follows:

      1. Certain Definitions. As used in this Registration Rights Agreement
("Agreement"), the following terms shall have the following respective meanings:

      "Commission" shall mean the Securities and Exchange Commission or any
other federal agency at the time administering the Securities Act.

      "Common Stock" shall mean the Company's Common Stock, $.001 par value per
share, as constituted as of the date of this Agreement.

      "Conversion Shares" shall mean shares of Common Stock issued upon
conversion of the Preferred Shares.

      "Exchange Act" shall mean the Securities Exchange Act of 1934, as amended,
or any similar federal statute, and the rules and regulations of the Commission
thereunder, all as the same shall be in effect at the time.

      "Holder" shall mean Duquesne Enterprises, its successors and assigns.

      "Restricted Stock" shall mean the Conversion Shares, excluding shares
which have been (a) registered under the securities Act pursuant to an effective
registration statement filed thereunder and disposed of in accordance with the
registration statement covering them, or (b) publicly sold pursuant to Rule 144
under the Securities Act, or (c) which may be sold privately.
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      "Securities Act" shall mean the Securities Act of 1933, as amended, or any
similar federal statute, and the rules and regulations of the Commission
thereunder, all as the same shall be in effect at the time.

      2. Registration Rights. If the Company at any time (other than in the
initial public offering) proposes to register any of its equity securities under
the Securities Act for sale to the public, whether for its own account or for
the account of other security holders or both (except with respect to
registration statements on Forms S-4, S-8, or an offering solely to its
stockholders, or another form not available for registering the Restricted Stock
for sale to the public), each such time it will give written notice to the
Holder of its intention so to do, provided that at such time the Holder is the
holder of Registrable Securities. Upon the Holder's written request, received by
the Company within 15 business days after the giving of any such notice by the
Company, to register any of the Holder's Restricted Stock, the Company will use
its best efforts to cause the Restricted Stock as to which registration shall
have been so requested to be included in the securities to be covered by the
registration statement proposed to be filed by the Company, all to the extent
requisite to permit the sale or other disposition by the Holder of such
Restricted Stock so registered. In the event that any registration pursuant to
this Section 2 shall be, in whole or in part, an underwritten public offering of
Common Stock, the number of shares of Restricted Stock to be included in such an
underwriting may be reduced (pro rata among the Holder and all other requesting
security holders having rights similar to the rights granted herein based upon
the number of shares of Restricted Stock owned by such holders) if and to the
extent that the managing underwriter shall be of the opinion that such inclusion
would adversely affect the marketing of the securities to be sold by the Company
therein.

      3. Registration Procedures.

            (a) If and whenever the company is required by the provisions of
Section 2 to use its best efforts to effect the registration of any shares of
Restricted Stock under the Securities Act, the Company will, as expeditiously as
possible:

                  (i) prepare and file with the Commission a registration
            statement (which, in the case of an underwritten public offering,
            shall be on Form S-1 or other form of general applicability
            satisfactory to the managing underwriter) with respect to such
            securities and use its best efforts to cause such registration
            statement to become and remain effective for the period of the
            distribution contemplated thereby (determined as hereinafter
            provided);

                  (ii) prepare and file with the Commission such amendments and
            supplements to such registration statement and the prospectus used
            in connection therewith as may be necessary to keep registration
            statement effective for the period specified in Section 3(i) above
            and comply with the provisions of the Securities Act with respect to
            the disposition of all Restricted Stock covered by such registration
            statement


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            in accordance with the Holder's intended method of disposition set
            forth in such registration statement for such period;

                  (iii) furnish to the Holder and other sellers and to each
            underwriter such number of copies of the registration statement and
            the prospectus included therein (including each preliminary
            prospectus) as such persons reasonably may request in order to
            facilitate the public sale or other disposition of the Restricted
            Stock covered by such registration statement;

                  (iv) use its best efforts to register or qualify the
            Restricted Stock covered by such registration statement under the
            securities or "blue sky" laws of such jurisdictions as the Holder,
            or, in the case of an underwritten public offering, the managing
            underwriter reasonably shall request; provided, however, that the
            Company shall not for any such purpose be required to qualify
            generally to transact business as a foreign corporation in any
            jurisdiction where it is not so qualified or to consent to general
            service of process in any such jurisdiction;

                  (v) use its best efforts to list or have admitted for trading
            the Restricted Stock covered by such registration statement with any
            securities exchange or listing agency (including Nasdaq) on which
            the Common Stock of the Company is then listed;

                  (vi) immediately notify the Holder and each underwriter under
            such registration statement, at any time when a prospectus relating
            thereto is required to be delivered under the Securities Act, of the
            happening of any event of which the Company has knowledge as a
            result of which the prospectus contained in such registration
            statement, as then in effect, includes an untrue statement of a
            material fact or omits to state a material fact required to be
            stated therein or necessary to make the statements therein not
            misleading in light of the circumstances then existing;

                  (vii) if the offering is underwritten and at the request of
            the Holder, use its best efforts to furnish on the date that
            Restricted Stock is delivered to the underwriters for sale pursuant
            to such registration: (A) an opinion dated such date of counsel
            representing the Company for the purposes of such registration,
            addressed to the underwriters and to the Holder, stating that such
            registration statement has become effective under the Securities
            Act, and that (1) to the best knowledge of such counsel, no stop
            order suspending the effectiveness thereof has been issued and no
            proceedings for that purpose have been instituted or are pending
            under the Securities Act, (2) the registration statement, the
            related prospectus and each amendment or supplement thereto comply
            as to form in all material respects with the requirements of the
            Securities Act (except that such counsel need not express any
            opinion as to financial statements contained therein), and (3) to
            such other effects as reasonably may be requested by


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            counsel for the underwriters or by the Holder or its counsel, and
            (B) a letter dated such date from the independent public accountants
            retained by the Company, addressed to the underwriters and to the
            Holder, stating that they are independent public accountants within
            the meaning of the Securities Act and that, in the opinion of such
            accountants, the financial statements of the Company included in the
            registration statement or the prospectus, or any amendment or
            supplement thereto, comply as to form in all material respects with
            the applicable accounting requirements of the Securities Act, and
            such letter shall additionally cover such other financial matters
            (including information as to the period ending no more than five
            business days prior to the date of such letter) with respect to such
            registration as such underwriters reasonably may request; and

                  (viii) make available for inspection by the Holder and any
            underwriter participating in any distribution pursuant to such
            registration statement and any attorney, accountant or other agent
            retained by the Holder or underwriter, all financial and other
            records, pertinent corporate documents and properties of the
            Company, and cause the Company's officers, directors and employees
            to supply all information reasonably requested by the Holder,
            underwriter, attorney, accountant or agent in connection with such
            registration statement.

            (b) For purposes of Section 3(i) and 3(ii) hereof, the period of
distribution of Restricted Stock in a firm commitment underwritten public
offering shall be deemed to extend until each underwriter has completed the
distribution of all securities purchased by it, and the period of distribution
of Restricted Stock in any other registration shall be deemed to extend until
the earlier of the sale of all Restricted Stock covered thereby and 120 days
after the effective date thereof.

            (c) In connection with each registration hereunder, the Holder will
furnish to the Company in writing such information with respect to itself and
the proposed distribution by it as reasonably shall be necessary in order to
assure compliance with federal and applicable state securities laws.

            (d) In connection with each registration pursuant to Section 2
hereof covering an underwritten public offering, the Company and the Holder
agree to enter into a written agreement with the managing underwriter in such
form and containing such provisions as are customary in the securities business
for such an arrangement between such underwriter and companies of the Company's
size and investment stature.

      4. Indemnification.

            (a) In the event of a registration of any of the Restricted Stock
under the Securities Act pursuant to Section 2, the Company will indemnify and
hold harmless the Holder, each underwriter of such Restricted Stock and each
other person, if any, who controls the Holder or underwriter within


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the meaning of the Securities Act, against any losses, claims, damages or
liabilities, joint or several, to which the Holder, underwriter or controlling
person may become subject under the Securities Act or otherwise, insofar as such
losses, claims, damages or liabilities (or actions in respect thereof) arise out
of or are based upon any untrue statement or alleged untrue statement of any
material fact contained in any registration statement under which such
Restricted Stock was registered under the Securities Act pursuant to Section 2,
any preliminary prospectus or final prospectus contained therein or any
amendment or supplement thereof, or arise out of or are based upon the omission
or alleged omission to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading, and will
reimburse the Holder, underwriter and controlling person for any legal or other
expenses reasonably incurred by them in connection with investigating or
defending any such loss, claim, damage, liability or action; provided, however,
that the Company will not be liable in any such case if and to the extent that
any such loss, claim, damage or liability arises out of or is based upon an
untrue statement or alleged untrue statement or omission or alleged omission so
made in conformity with information furnished by the Holder, underwriter or
controlling person in writing specifically for use in such registration
statement or prospectus.

            (b) In the event of a registration of any of the Restricted Stock
under the Securities Act pursuant to Section 2, the Holder will indemnify and
hold harmless the Company, each person, if any, who controls the Company within
the meaning of the Securities Act, each officer of the Company who signs the
registration statement, each director of the Company, each underwriter and each
person who controls any underwriter within the meaning of the Securities Act,
against all losses, claims, damages or liabilities, joint or several, to which
the Company or such officer, director, underwriter or controlling person may
become subject under the Securities Act or otherwise, insofar as such losses,
claims, damages or liabilities (or actions in respect thereof) arise out of or
are based upon any untrue statement or alleged untrue statement of any material
fact contained in the registration statement under which such Restricted Stock
was registered under the Securities Act pursuant to Section 2, any preliminary
prospectus or final prospectus contained therein, or any amendment or supplement
thereof, or arise out of or are based upon the omission or alleged omission to
state therein a material fact required to be stated therein or necessary to make
the statements therein not misleading, and will reimburse the Company and each
such officer, director, underwriter and controlling person for any legal or
other expenses reasonably incurred by them in connection with investigating or
defending any such loss, claim, damage, liability or action; provided, however,
that the Holder will be liable hereunder in any such case if and only to the
extent that any such loss, claim, damage or liability arises out of or is based
upon an untrue statement or alleged untrue statement or omission or alleged
omission made in reliance upon and in conformity with information pertaining to
the Holder, as such, furnished in writing to the Company by the Holder
specifically for use in such registration statement or prospectus; and further,
provided, that the liability of the Holder hereunder shall be limited to an
amount equal to the proceeds to the Holder of Restricted Stock sold as
contemplated herein.

            (c) Promptly after receipt by an indemnified party hereunder of
notice of the commencement of any action, such indemnified party shall, if a
claim in respect thereof is to be made


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against the indemnifying party hereunder, notify the indemnifying party in
writing thereof, but the omission so to notify the indemnifying party shall not
relieve it from any liability which it may have to such indemnified party other
than under this Section 4 and shall only relieve it from any liability which it
may have to such indemnified party under this Section 4 if and to the extent the
indemnifying party is prejudiced by such omission. In case any such action shall
be brought against any indemnified party and it shall notify the indemnifying
party of the commencement thereof, the indemnifying party shall be entitled to
participate in and, to the extent it shall wish, to assume and undertake the
defense thereof with counsel satisfactory to such indemnified party, and, after
notice from the indemnifying party to such indemnified party of its election so
to assume and undertake the defense thereof, the indemnifying party shall not be
liable to such indemnified party under this Section 4 for any legal expenses
subsequently incurred by such indemnified party in connection with the defense
thereof other than reasonable costs of investigation and of liaison with counsel
so selected; provided, however, that, if the defendants in any such action
include both the indemnified party and the indemnifying party and the
indemnified party shall have reasonably concluded that the interests of the
indemnified party reasonably may be deemed to conflict with the interests of the
indemnifying party, the indemnified party shall have the right to select a
separate counsel and to assume such legal defenses and otherwise to participate
in the defense of such action, with the expenses and fees of such separate
counsel and other expenses related to such participation to be reimbursed by the
indemnifying party as incurred.

      5. Changes in Common Stock or Preferred Stock. If, and as often as, there
is any change in the Common Stock or the Preferred Stock by way of a stock
split, stock dividend, combination or reclassification, or through a merger,
consolidation, reorganization or recapitalization, or by any other means,
appropriate adjustment shall be made in the provisions hereof so that the rights
and privileges granted hereby shall continue with respect to the Common Stock or
the Preferred Stock as so changed.

      6. Rule 144 Reporting. With a view to making available the benefits of
certain rules and regulations of the Commission which may at any time permit the
sale of the Restricted Stock to the public without registration, at all times
after 90 days after any registration statement covering a public offering of
securities of the Company under the Securities Act shall have become effective,
the Company agrees to:

            (a) make and keep public information available, as those terms are
understood and defined in Rule 144 under the Securities Act;

            (b) use its best efforts to file with the Commission in a timely
manner all reports and other documents required of the Company under the
Securities Act and the Exchange Act; and

            (c) furnish to the Holder forthwith upon request a written statement
by the Company as to its compliance with the reporting requirements of Rule 144
and of the Securities Act and the Exchange Act, a copy of the most recent annual
or quarterly report of the Company and such other reports and documents so filed
by the Company as such holder may reasonably request in availing itself


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of any rule or regulation of the commission allowing the Holder to sell any
Restricted Stock without registration.

      7. Representations and Warranties of the Company. The Company represents
and warrants to the Holder as follows:

            (a) The execution, delivery and performance of this Agreement by the
Company have been duly authorized by all requisite corporate action and will not
violate any provision of law, any order of any court or other agency of
government, the Charter or Bylaws of the Company or any provision of any
indenture, agreement or other instrument to which it or any or its properties or
assets is bound, conflict with, result in a breach of or constitute (with due
notice or lapse of time or both) a default under, any such indenture, agreement
or other instrument or result in the creation or imposition of any lien, charge
or encumbrance of any nature whatsoever upon any of the properties or assets of
the Company.

            (b) This Agreement has been duly executed and delivered by the
Company and constitutes the legal, valid and binding obligation of the Company,
enforceable in accordance with its terms, subject to applicable bankruptcy,
moratorium and other laws generally affecting the rights and remedies of
creditors.

            (c) The Company represents and warrants that it shall not enter into
any other agreement with any holder or prospective holder of any securities of
the Company which would be inconsistent with the terms and provisions contained
in this Agreement.

      8. Miscellaneous.

            (a) All covenants and agreements contained in this Agreement by or
on behalf of any of the parties hereto shall bind and inure to the benefit of
the respective successors and assigns of the parties hereto (including, without
limitation, transferees of any Preferred Shares or Restricted Stock), whether so
expressed or not.

            (b) All notices, requests, consents and other communications
hereunder shall be in writing and shall be mailed by certified or registered
mail, return receipt requested, postage prepaid, or telexed, in the case of
non-U.S. residents, addressed as follows:

                  (i) If to the Company or to the Holder, at the address of such
            party set forth in the Purchase Agreement, with appropriate copies
            as noted therein;

                  (ii) If to any subsequent holder of Preferred Shares or
            Restricted Stock, to it at such address as may have been furnished
            to the Company in writing by such holder;


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or, in any case, at such other address or addresses as shall have been furnished
in writing to the Company (in the case of the Holder) or to the Holder (in the
case of the Company) in accordance with the provisions of this paragraph.

            (c) This Agreement shall be governed by and construed in accordance
with the laws of the State of Delaware.

            (d) This Agreement may not be amended or modified, and no provision
hereof may be waived, without the written consent of the Company and the Holder.

            (e) This Agreement may be executed in two or more counterparts, each
of which shall be deemed an original, but all of which together shall constitute
one and the same instrument.

            (f) If requested in writing by the underwriters for the initial
underwritten public offering of securities of the Company, the Holder shall
agree not to sell publicly any shares of Restricted Stock or any other shares of
Common Stock (other than shares of Restricted Stock or other shares of Common
Stock being registered in such offering), without the consent of such
underwriters, for a period of not more than 180 days following the effective
date of the registration statement relating to such offering; provided, however,
that all persons entitled to registration rights with respect to shares of
Common Stock who are not parties to this Agreement, all other persons selling
shares of Common Stock in such offering and all executive officers and directors
of the Company, shall also have agreed not to sell publicly their Common Stock
under the circumstances and pursuant to the terms set forth in this Section
8(f).

            (g) Notwithstanding the provisions of Section 3(a) hereof, the
Company's obligation to file a registration statement, or cause such
registration statement to become and remain effective, shall be suspended for a
period not to exceed 90 days in any 12-month period if there exists at the time
material non-public information relating to the Company which, in the reasonable
opinion of the Board of Directors of the Company, should not be disclosed.

            (h) If any provision of this Agreement shall be held to be illegal,
invalid or unenforceable, such illegality, invalidity or unenforceability shall
attach only to such provision and shall not in any manner affect or render
illegal, invalid or unenforceable any other provision of this Agreement, and
this Agreement shall be carried out as if any such illegal, invalid or
unenforceable provision were not contained herein.


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            Please indicate your acceptance of the foregoing by signing and
returning the enclosed counterpart of this Agreement, whereupon this
Registration Rights Agreement shall be a binding agreement between the Company
and you.


                                    Very truly yours,

                                    H POWER CORP.


                                    By: /s/ R. C. Cope
                                       ---------------------------------------

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

Accepted and agreed to,
with the intent to be legally bound,
this 25th day of March, 1996.


DUQUESNE ENTERPRISES


By:    /s/ Anthony Villioti
       ---------------------------------------
Title: Vice President
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