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                           FIFTH AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION

                                       OF

                            BEACON POWER CORPORATION

     The name of the Corporation is Beacon Power Corporation. The Corporation
was originally incorporated on May 8, 1997 pursuant to Sections 242 and 245
of the General Corporation Law of the State of Delaware. This Fifth Amended
and Restated Certificate of Incorporation of Beacon Power Corporation was
proposed and declared advisable by the Board of Directors of the Corporation
on ________, 2000 and was consented to in writing by the Corporation's
stockholders as of ________, 2000, in accordance with Sections 228, 242 and
245 of the General Corporation Law of the State of Delaware. The
Corporation's Amended and Restated Certificate of Incorporation is hereby
amended and restated in its entirety to read as follows:

     FIRST:  The name of the Corporation is Beacon Power Corporation.

     SECOND:  The address of its registered office in the State of Delaware
is Corporation Trust Center, 1209 Orange Street, in the City of Wilmington,
County of New Castle. The name of its registered agent at such address is The
Corporation Trust Company.

     THIRD:  The nature of the business or purposes to be conducted or
promoted by the Corporation is as follows:

     To engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of Delaware.

     FOURTH:  The total number of shares of all classes of stock which the
Corporation shall have authority to issue is 110,000,000 shares of common
stock, $0.01 par value per share ("Common Stock") and 10,000,000 shares of
preferred stock, $0.01 par value per share to be determined, ("Preferred
Stock").

     The following is a statement of the designations and the powers,
privileges and rights, and the qualifications, limitations or restrictions
thereof in respect of each class of capital stock of the Corporation.


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A.   COMMON STOCK.

     1.  GENERAL. 110,000,000 shares of Common Stock may be issued from time
to time as determined by the Board of Directors. The voting, dividend and
liquidation rights of the holders of the Common stock are subject to and
qualified by the rights of the holders of the Preferred Stock of any series
as may be designated by the Board of Directors upon any issuance of the
Preferred Stock of any series.

     2.  VOTING. The holders of the Common Stock are entitled to one vote for
each share held at all meetings of stockholders (and written actions in lieu
of meetings). There shall be no cumulative voting.

     3.  DIVIDENDS. Dividends may be declared and paid on the Common Stock
from funds lawfully available therefor as and when determined by the Board of
Directors and subject to any preferential dividend rights of any then
outstanding Preferred Stock.

     4.  LIQUIDATION. Upon the dissolution or liquidation of the Corporation,
whether voluntary or involuntary, holders of Common Stock will be entitled to
receive all assets of the Corporation available for distribution to its
stockholders, subject to any preferential rights of any then outstanding
Preferred Stock.

B.   PREFERRED STOCK.

     1.  ISSUANCE. 10,000,000 shares of Preferred Stock may be issued from
time to time as determined by the Board of Directors. The Board of Directors
is hereby authorized to designate each series, to establish the number of
shares to be included in each series and to determine or alter the rights,
preferences, privileges, and restrictions granted to or imposed upon any
wholly unissued series of Preferred Stock and, within the limits and
restrictions stated in any resolution or resolutions of the Board of
Directors originally fixing the number of shares constituting any such
additional series, to increase or decrease (but not below the number of
shares of such series then outstanding) the number of shares of any such
additional series subsequent to the issue of shares of that series.

     2.  RIGHTS. Authorized and unissued shares of Preferred Stock may be
issued with such designations, voting powers, preferences, and relative,
participating, option or other special rights, and qualifications,
limitations and restrictions on such rights, as the Board of Directors may
authorize by resolutions duly adopted prior to the issuance of any shares of
series of Preferred Stock, including, but not limited to: (i) the distinctive
designation of each series and the number of shares that will constitute such
series; (ii) the voting rights, if any, of shares of such series and whether
the shares of any such series having voting rights shall have multiple or
fractional votes per share; (iii) the dividend rate on the shares of such
series, any restriction, limitation, or condition upon the payment of such
dividends, whether dividends shall be cumulative, and the dates on which
dividends are payable; (iv) the prices at which, and the terms and conditions
on which, the shares of such series may be redeemed, if such shares are
redeemable; (v) the purchase or sinking fund provisions, if any, for the
purchase or redemption of shares of such series; (vi) any preferential amount
payable upon shares of such series in the event

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of the liquidation, dissolution, or winding-up of the Corporation, or the
distribution of its assets; and (vii) the prices or rates of conversion at
which, the terms and conditions on which, the shares are convertible.

     FIFTH:  In furtherance of and not in limitation of powers conferred by
statute, it is further provided:

     1.  Election of directors need not be by written ballot.

     2.  The Board of Directors is expressly authorized to adopt, amend or
repeal the By-Laws of the Corporation.

     SIXTH:  Except to the extent that the General Corporation Law of
Delaware prohibits the elimination or limitation of liability of directors
for breaches of fiduciary duty, no director of the Corporation shall be
personally liable to the Corporation or its stockholders for monetary damages
for any breach of fiduciary duty as a director, notwithstanding any provision
of law imposing such liability. No amendment to or repeal of this provision
shall apply to or have any effect on the liability or alleged liability of
any director of the Corporation for or with respect to any acts or omissions
of such director occurring prior to such amendment.

     SEVENTH:  The Corporation shall, to the fullest extent not prohibited by
Section 145 of the General Corporation Law of Delaware, as amended from time
to time, indemnify each person who was or is a party or is threatened to be
made a party to any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative, by
reason of the fact that he is or was, or has agreed to become, a director or
officer of the Corporation, or is or was serving, or has agreed to serve, at
the request of the Corporation, as a director, officer or trustee of, or in a
similar capacity with, another corporation, partnership, joint venture, trust
or other enterprise (including any employee benefit plan) (all such persons
being referred to hereafter as an "Indemnitee"), or by reason of any action
alleged to have been taken or omitted in such capacity, against all expenses
(including attorneys' fees), judgments, fines and amounts paid in settlement
actually and reasonably incurred by or on behalf of an Indemnitee in
connection with such action, suit or proceeding and any appeal therefrom.

     As a condition precedent to his right to be indemnified, the Indemnitee
must notify the Corporation in writing as soon as practicable of any action,
suit proceeding or investigation involving him for which indemnity will or
could be sought. With respect to any action, suit, proceeding or
investigation of which the Corporation is so notified, the Corporation will
be entitled to participate therein at its own expense and/or to assume the
defense thereof at its own expense, with legal counsel reasonably acceptable
to the Indemnitee.

     In the event that the Corporation does not assume the defense of any
action, suit, proceeding or investigation of which the Corporation receives
notice under this Article, the Corporation shall pay in advance of the final
disposition of such matter any expenses (including attorneys' fees) incurred
by an indemnitee in defending a civil or criminal action, suit, proceeding or
investigation or any appeal therefrom; PROVIDED, HOWEVER, that the payment of
such expenses incurred by an Indemnitee in advance of the final disposition
of such matter shall

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be made only upon receipt of an undertaking by or on behalf of the Indemnitee
to repay all amounts so advanced in the event that it shall ultimately be
determined that the Indemnitee is not entitled to be indemnified by the
Corporation as authorized in this Article, which undertaking shall be
accepted without reference to the financial ability of the Indemnitee to make
such repayment; and FURTHER PROVIDED that no such advancement of expenses
shall be made if it is determined that the Indemnitee did not act in good
faith and in a manner he reasonably believed to be in, or not opposed to, the
best interests of the Corporation, and, with respect to any criminal action
or proceeding, had no reasonable cause to believe his conduct was unlawful.

     If a claim for indemnification or advancement of expenses hereunder is
not paid in full by the Corporation within sixty (60) days after a written
claim has been received by the Corporation, the Indemnitee may at any time
thereafter bring suit against the Corporation to recover the unpaid amount of
the claim, and if successful in whole or in part, the Indemnitee shall be
entitled to be paid the expenses he incurrred in prosecuting such claim.

     The Corporation shall not indemnify an Indemnitee to the extent such
Indemnitee is reimbursed from the proceeds of insurance, and in the event the
Corporation makes any indemnification payments to an Indemnitee and such
Indemnitee is subsequently reimbursed from the proceeds of insurance, such
Indemnitee shall promptly refund such indemnification payments to the
Corporation to the extent of such insurance reimbursement.

     All determinations hereunder as to the entitlement of an Indemnitee to
indemnification or advancement of expenses shall be made in each instance by
(a) a majority vote of the directors of the Corporation consisting of persons
who are not at that time parties to the action, suit or proceeding in
question ("disinterested directors"), whether or not a quorum, (b) a majority
vote of a quorum of the outstanding shares of stock of all classes entitled
to vote for directors, voting as a single class, which quorum shall consist
of stockholders who are not at that time parties to the action, suit or
proceeding in question, (c) independent legal counsel (who may, to the extent
permitted by law, be regular legal counsel to the Corporation), or (d) a
court of competent jurisdiction.

     The Indemnification rights provided in this Article (i) shall not be
deemed exclusive of any other rights to which an Indemnitee may be entitled
under any law, agreement or vote of stockholders or disinterested directors
or otherwise, and (ii) shall inure to the benefit of the heirs, executors and
administrators of the Indemnitees. The Corporation may, to the extent
authorized from time to time by its Board of Directors, grant indemnification
rights to other employees or agents of the Corporation or other persons
serving the Corporation and such rights may be equivalent to, or greater or
less than, those set forth in this Article.

     EIGHTH:  Commencing with the 2001 annual meeting of stockholders of the
Corporation, the directors of the Corporation shall be divided, with respect
to the time for which they severally hold office, into three classes, as
nearly equal in number as possible, with the term of office of the first
class to expire at the 2002 annual meeting of the stockholders of the
Corporation, the term of office of the second class to expire at the 2003
annual meeting of the stockholders of the Corporation and the term of office
of the third class to expire at the 2004

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annual meeting of the stockholders of the Corporation, with each director to
hold office until his or her successor shall have been duly elected and
qualified. Such provisions shall further provide that at each annual meeting
of stockholders of the Corporation, commencing with the 2001 annual meeting,
directors elected to succeed those directors whose terms then expire shall be
elected for a term of office to expire at the third succeeding annual meeting
of stockholders of the Corporation after their election.

     NINTH:  Subject to the approval rights of holders of Common Stock or
Preferred Stock set forth in this Amended and Restated Certificate, the
Corporation reserves the right to amend, alter, change or repeal any
provision contained in this Amended and Restated Certificate of
Incorporation, in the manner now or hereafter prescribed by statute and this
Amended and Restated Certificate of Incorporation, and all rights conferred
upon stockholders herein are granted subject to this reservation.

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EXECUTED at Woburn, Massachusetts, on __________, 2000.




                                       ------------------------------------
                                       Maureen Lister, Secretary

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