Exhibit 10.25

                              PLUG POWER, L.L.C.

                                    SECOND
                           AMENDMENT AND RESTATEMENT
                                    OF THE
                            MEMBERSHIP OPTION PLAN

                               February 15, 1999


     WHEREAS, Plug Power, L.L.C., a limited liability company organized under
the laws of the State of Delaware ("Company") entered into a Membership Option
Plan and Agreement, effective as of the 1st day of July, 1997 (the "Plan"); and

     WHEREAS, the Company desires to amend the Plan to provide consultants the
opportunity to acquire Class B membership interests in the Company and to share
in its success, with the added incentive to work effectively for and in the
Company's interest; and

     WHEREAS, at a special meeting of the Members of Company held on January 26,
1999, at which all of the Members were present, either by person or by
telephone, and acting with full authority, the Members unanimously agreed to
amend the limited liability company agreement to permit the company to provide
consultants the opportunity to acquire Class B membership interests in the
Company, subject to the specific prior approval by the board of managers for
each consulting contract that provides stock options as part of the contract;
and

     WHEREAS, the Company desires to also amend the Plan to include in the
definition of "Employees" eligible to participate in the Plan those employees of
the Company who become directly employed by GE Fuel Cell Systems, L.L.C.
("GEFCS"); and

     WHEREAS, such former employees shall be subject to the same terms and
conditions of the Plan; and

     NOW, THEREFORE, the text of the original Plan as amended is hereby amended
and restated in its entirety to read as follows:

     Agreement, made and effective as of the 15th day of February, by Plug
Power, L.L.C., a limited liability company organized under the laws of the State
of Delaware ("Company").

     WHEREAS, Company is a limited liability corporation with Class A membership
interests and Class B membership interests, and

     WHEREAS, Company has determined that its interests will be advanced and
best served by providing an incentive to its current employees, certain former
employees and certain consultants, to acquire Class B membership interests in
Company and to share in its success, with the added incentive to work
effectively for and in Company's interest,



     NOW THEREFORE, Company hereby establishes the Plan as follows:

ESTABLISHMENT OF PLAN

     The Plan shall be known as the Plug Power Membership Option Plan ("Plan"),
and shall be effective on the date first above written.

ELIGIBILITY

     Employees. All employees of Company shall participate in the Plan on its
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effective date.  An Employee who is eligible to participate in the Plan, as set
forth on Exhibit "A" is hereinafter referred to as "Employee", or in the plural,
as "Employees." Members of the Board of Managers ("Managers") of the Company
and/or Corporations named in lieu of a Manager, as set forth on Exhibit "B",
shall also participate in the Plan on its effective date.  In addition,
employees of the Company who become directly employed GE Fuel Cell Systems,
L.L.C.  ("GEFCS Employees") shall also be eligible to participate in the Plan.
Hereafter, in this Plan, Managers and/or Corporations and/or GEFCS Employees
shall be referred to as "Employees", and shall be subject to the remaining
provisions of this Plan as though they were Employees, unless specifically
provided otherwise.

     Consultants.  The board of managers of the Company shall determine those
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consultants of Company, as set forth on Exhibit "C", eligible to participate in
the Plan on its effective date.  A Consultant who is eligible to participate in
the Plan and who is shown on the attached Exhibit "C" is hereinafter referred to
as "Consultants", or in the plural, as "Consultants."

GRANT OF OPTIONS

     Employees.  Company hereby grants to the Employees, as shown on Exhibit "A"
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(Employees) and Exhibit "B" (Managers), as a matter of separate agreement and
not in lieu of any other compensation to which such Employees may be otherwise
entitled, the right and option, hereinafter called "Option", or "Options", to
purchase the number shares of Class B membership interests of the Company, at
such times, and in such amounts, as the Company shall determine, on the terms
and conditions hereinafter set forth.

     Company may, from time to time, grant additional Options to Employees.

     Consultants.  Company hereby grants to the Consultants, as shown on Exhibit
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"C", as a matter of separate agreement, the right and option, hereinafter called
"Option" or "Options", to purchase the number shares of class B membership
interests of the Company, at such times, and in such amounts, on the terms and
conditions hereinafter set forth.

     Company may, from time to time, amend Exhibit "C", as may be required to
add new Consultants who become eligible for the Plan, or to grant additional
Options to Consultants, but not without the prior authorization of the board of
managers.

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OPTION PRICE

     The option exercise price for shares of Class B membership interests shall
be set forth on Exhibit "A" for Employees, Exhibit "B" for Managers, and Exhibit
"C" for Consultants, and shall be determined by the Company's board of managers
and which price shall represent the fair value of Company stock on the grant
date.

WHEN OPTIONS ARE EXERCISABLE

     Employees.  Options shall be exercisable by Employees only after such
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Options have vested.  Furthermore, no options may be exercised, even if vested,
prior to July 1, 2000, except as provided in sub-paragraphs (f) and (a) below.

     Vesting under this Plan is determined by an Employee's length of service
with the Employer, measured from an Employee's date of hire by the Employer,
provided however, that if an Employee's direct prior employer was either
Mechanical Technology, Inc. or Detroit Edison, such Employees prior service
(measured from his date of hire) with either Mechanical Technology, Inc. or
Detroit Edison shall be counted as service for purposes of this Plan.

     Options shall vest as follows.

     (a)  If an Employee has completed 12 months of continuous service as of the
          date of the option grant, such Employee shall immediately be 20%
          vested in the Options granted. If an Employee has not completed 12
          months of continuous service as of the date of Option grant, he shall
          become 20% vested in his Options once he has completed twelve months
          of continuous service.

     (b)  An additional 20% of Options shall vest on the first 12 month
          anniversary from the date of original Option grant.

     (c)  An additional 20% of Options shall vest on the second 12 month
          anniversary from the date of original Option grant.

     (d)  An additional 20% of Options shall vest on the third 12 month
          anniversary from the date of original Option grant.

     (e)  An additional 20% of Options shall vest on the fourth 12 month
          anniversary from the date of original Option grant.

     (f)  All Options originally granted shall become immediately vested and
          exercisable in the event of the sale of all or substantially all of
          the Company's assets, or in the event of the sale of all or
          substantially all of the Company's Class A membership interests.

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     (g)  All vested options shall become immediately exercisable in the event
          the Company's Class A membership interests become publicly traded.

     (h)  Notwithstanding sub-paragraphs (a) through (e) above, Options granted
          to Managers, shall vest as follows:

          (1)  50% of Options granted to Managers shall vest immediately upon
               grant.

          (2)  An additional 25% of Options granted to Managers shall vest 12
               months following grant.

          (3)  An additional 25% of Options granted to Managers shall vest 24
               months following date of grant.

     Options granted under this Agreement shall automatically expire, and be
null and void, ten (10) years after the date of grant, except in the death of an
Employee.

     In the event that an Employee's employment shall be terminated for any
reason except death, any Options held by the affected Employee, and exercisable,
must be exercised, if at all, within a period of one (1) month following any
such termination.  Any Options outstanding and not exercised within such one (1)
month period shall become void.  In no event shall this one (1) month period be
in addition to the ten (10) year option periods described in the paragraph
immediately preceding,

     In the event of the death of an Employee while holding Options which were
exercisable on the date of death, the estate or beneficiary of such Employee
shall have the right to exercise any such outstanding Options for a period of
one (1) year following death, even if such extended exercise period extends
beyond the ten (10) year option period.  The Options granted by this agreement
shall not be transferable by the Employee other than by will or the laws of
descent and distribution.

     Consultants.  Options shall be exercisable by Consultants only after such
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Options have vested.  Furthermore, no options may be exercised, even if vested,
prior to July 1, 2000, except as provided in sub-paragraphs (d) and (e) below.

     Options shall vest as follows:

     (a)  One-third (1/3) of the Options shall vest upon the expiration of
          Consultant's initial contract term.

     (b)  An additional one-third (1/3) of the Options shall vest on the first
          12 month anniversary of the expiration of the initial contract term.

     (c)  The remaining one-third (1/3) of Options shall vest on the second 12
          month anniversary of the expiration of the initial contract term.

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     Options shall vest in accordance with the foregoing schedule regardless of
whether Consultant's initial contract terminates prior to the expiration of the
contract term or whether Consultant's contract is renewed.  Vesting, however, is
subject to and contingent upon Consultant complying with the non-compete
obligations set forth in his/her consulting contract. Additionally, should
Consultant, at any time, provide services for, or work for a competing company,
then all outstanding options, whether vested or not, become immediately null and
void.  If for any reason Consultant does not complete the contracted work as is
evident by Consultant receiving less than the original contracted revenue, then
the awarded options will be proportionately reduced to reflect the same
percentage as cash paid versus original contract revenue.

     (d)  Options originally granted shall become immediately vested and
          exercisable in the event of the sale of all or substantially all of
          the Company's assets, or in the event of the sale of all or
          substantially all of the Company's Class A membership interests.

     (e)  All vested options shall become immediately exercisable in the event
          the Company's Class A membership interests become publicly traded.

     Options granted under this Agreement shall automatically expire, and be
null and void, five (5) years after the date of grant, except in the death of a
Consultant.

     In the event of the death of a Consultant while holding Options which were
exercisable on the date of death, the estate or beneficiary of such Consultant
shall have the right to exercise any such outstanding Options for a period of
one (1) year following death, even if such extended exercise period extends
beyond the five (5) year option period.  The Options granted by this agreement
shall not be transferable by the Consultant other than by will or the laws of
descent and distribution.

HOW OPTIONS ARE EXERCISABLE

     An Employee, Consultant or his/her estate or beneficiary shall exercise the
Options granted by this agreement by written notice to the Company, which notice
shall specify the number of Class B membership interests to be purchased, and
which shall be accompanied by a check in full payment of the option price for
such Class B membership interests.  Until such payment, an Employee, Consultant
or his/her estate or beneficiary shall have no rights in the optioned Class B
membership interests.

     Until such time as the Company's membership interests or stock is publicly
traded or until such time that the board of managers amend this agreement, the
Employee and Consultant agrees that all interests purchased by him/her, his/her
estate or beneficiary under the Plan are

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acquired for investment and not for distribution. The Employee and Consultant
also agrees that any notice of exercise of the Option shall become accompanied
by a written representation, signed by the Employee and/or Consultant, to that
effect.

     If the Company ever commences a public offering of its securities, it is
likely the Company's membership interests will be reclassified into shares of
common stock.  Such reclassification will be structured so that Employee's
and/or Consultant's percentage of ownership or interest in the Company is not
diluted.  Employees and Consultants also understand that should the Company's
membership interests or stock become publicly traded, there may be certain
restrictions placed on the sale of interests held by Employees and/or
Consultants, and other insiders, for a period of up to one year or longer, as
determined by the underwriter of any such transaction.

     Employees and Consultants further understand that neither the Company, its
officers, nor its board of managers can guarantee or promise that the Company's
membership interests or stock will ever be registered or publicly traded.
Additionally, there may never be a market for any such Company membership
interests or stock, and that such Company membership interests or stock may be
unmarketable.

     The Company shall have no duty or obligation to repurchase any or all of
its outstanding Class B membership interests.

CONTINUED SERVICE

     Employees.  Employee, in consideration of the granting of Options to
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him/her, agrees that he/she will continue to render services to the Company
except as he/she may be prevented from doing so by death, disability,
retirement, or termination.

     Nothing in the Plan shall be deemed to confer to an Employee any guaranteed
right to continue to be employed by the Company, or interfere in any way with
the right of the Company to terminate his/her employment, as provided by the by-
laws of the Company or as provided by law.

     Consultants.  Nothing in the Plan shall be deemed to confer to a Consultant
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any guaranteed right to continue to be under contract by the Company, or
interfere in any way with the right of the Company to terminate his/her
contract, as provided by the by-laws of the Company or as provided by law.

TAX EFFECTS

     Employees and Consultants understand that there may be both federal and
state income tax consequences associated with the exercise of the Options
granted by the Plan, including withholding requirements.  Employees acknowledge
that they have conferred with their

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respective counsel regarding any and all such tax consequences, and that in no
event shall Company be liable or responsible for any such tax liability.

GOVERNING LAW

     The Plan shall be governed by the law of the State of New York.

     IN WITNESS WHEREOF, Corporation has caused this agreement to be executed on
the date of first above written.

Plug Power, L.L.C.


By:  /s/ Gary Mittleman
   -----------------------------------
     Gary Mittleman
     President Chief Executive Officer

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                              FIRST AMENDMENT TO
                       SECOND AMENDMENT AND RESTATEMENT
                                    OF THE
                            MEMBERSHIP OPTION PLAN

                              PLUG POWER, L.L.C.


     This First Amendment to Second Amendment and Restatement of the Membership
Option Plan (the "Option Plan") is effective as of first day of October, 1999,
and amends the Option Plan, dated as of February 15, 1999;

     WHEREAS, Plug Power, L.L.C. (the "Company") desires to amend the Option
Plan to provide for the ability of the Company to vary the terms of vesting and
exercisability of options granted under the Option Plan;

     WHEREAS, at a meeting of the Members of the Company held on October 1,
1999, at which all Members were present, either by person or by telephone, and
acting with full authority, the Members  agreed to amend the Option Plan, as set
forth below;

     NOW, THEREFORE, the Option Plan is hereby amended as follows:


1.   On page 5 of the Option Plan, before the title "How Options Are
Exercisable", insert the following sentence in a new paragraph:

"Notwithstanding anything to the contrary provided herein, the Company may, at
its option, provide for different time limitations for vesting and
exercisability of Options by written agreement with the grantee of such
options."

2.   The remainder of the Option Plan shall continue in full force and effect.

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