BEACON POWER CORPORATION
                         RESTRICTED STOCK UNIT AGREEMENT

         This Restricted Stock Unit Agreement (the "Agreement"), dated as of
February 15, 2005 (the "Effective Date"), is by and between Beacon Power
Corporation ("Company") and _____________________ ("Employee"), an employee of
Company.

         WHEREAS, this Agreement is intended to provide Employee deferred
compensation in the form of restricted stock units (or "RSUs") that convert into
shares of Company's common stock, in lieu of a cash bonus, through establishing
and evaluating targets and awards for Employee, with Employee having the right
to convert his or her RSUs into shares at any time after such grant;

         NOW THEREFORE, it is agreed as follows:

1.   Accrual and Grant of Restricted Stock Unit Award.

     (a) General.  Subject to the terms and  conditions  of this  Agreement  and
pursuant to Company's Second Amended and Restated 1998 Stock Incentive Plan (the
"Plan"), Company hereby accrues, and thereafter to grant, RSUs to Employee based
on Employee's  having  achieved  certain  targets,  as described on the attached
Schedule A with respect to 2004.

     (b) Grants of Accrued  RSUs.  As RSUs have  accrued for 2004 (as  described
above in  paragraph  (a)),  then on the four grant dates set forth in Schedule B
(each a "Grant  Date"),  the Company  shall be considered to have granted to the
Employee  one-fourth of the total of RSUs so accrued.  Thus,  accruals from 2004
result in grants in 2005.

2.   Conversion to Common Stock.

     Each RSU  shall  represent  the  right to  receive  one (1) share of Common
Stock,  subject to the terms and  conditions of this  Agreement.  Employee shall
have the right to convert each granted RSU into one (1) share of Common Stock at
any time on or after the applicable Grant Date, by delivering  written notice of
such exercise to Company;  provided,  that, if the applicable  Grant Date occurs
during  a  period  in which  Employee  is (a)  subject  to a  lock-up  agreement
restricting  Employee's  ability to sell Common  Stock in the open  market,  (b)
restricted from selling Common Stock in the open market because a trading window
is not  available,  in the opinion of Company,  or (c) trading is otherwise  not
appropriate, in the opinion of Company, Employee's right to convert such granted
RSUs into  shares of Common  Stock shall be delayed  until the date  immediately
following the  expiration  of the lock-up  agreement or the opening of a trading
window or confirmation  by Company that trading is appropriate,  as the case may
be.

3.   Termination of Employment.

Notwithstanding anything in this Agreement to the contrary:

     (a) RSUs That Are Already Accrued and Granted. If Employee's  employment is
terminated  by either  party,  Employee  will retain all RSUs which have already
been granted  (pursuant to the Grant Dates in Schedule B) to Employee before the
"Termination  Notice Date",  defined to mean the date on which Employee notifies
Company that Employee will resign (if earlier than the date of  resignation)  or
the date on which Company  notifies  Employee that employment will be terminated
(if earlier than the date of  termination).  Also,  Employee  shall not have the
right to  receive  a grant of any RSUs  with  respect  to the  period  after the
Termination Notice Date.

     (b) RSUs That Are  Accrued,  but Not Yet  Granted,  Before the  Termination
Notice. If Employee's  employment is terminated by Company,  then Employee shall
also have the right to continue  receiving  grants  with  respect to the accrual
period ending on the Termination Notice Date (including, if applicable,  for the
pro rata portion of any partial  quarter before such  Termination  Notice Date).
Such  grants  shall  occur on the  timetable  specified  in  Schedule  B. If the
employment is terminated by the Employee,  then Employee will not be entitled to
receive grants of RSUs that might have accrued before Termination Notice.

4.   Nontransferability of Agreement and RSUs.

     This Agreement and the RSUs may not be sold, assigned, transferred, pledged
or otherwise encumbered by Employee,  either voluntarily or by operation of law,
except by will or the laws of  descent  and  distribution.  Notwithstanding  the
foregoing,  Employee's  transfer  to a  revocable  trust  that is solely for the
benefit of  Employee  and  Employee's  spouse  and/or  issue  during  Employee's
lifetime  and  transfer  under such  trust at  Employee's  death to the  trust's
intended  beneficiaries  shall not be deemed to be  prohibited  by the foregoing
provisions.  If any person other than Employee,  Employee's then current spouse,
and  Employee's  issue shall possess a vested  interest in such trust during the
lifetime of Employee,  such interest shall not be recognized hereunder as giving
such person any right to the  benefit of any RSUs or the shares of Common  Stock
issuable  upon  conversion  thereof.  In such  event  the RSUs  shall  revest in
Employee as if such transfer in trust had not occurred.

5.   No Right to Continued Employment.

     This  Agreement  shall not confer upon  Employee  any right with respect to
continuance of employment by Company, nor shall it interfere in any way with the
right of Company to terminate Employee's employment at any time.

6.   No Right as Stockholder.

     Employee  shall not be entitled to vote any shares of Common Stock that may
be acquired  through  conversion of RSUs to Common Stock,  shall not receive any
dividends  attributed  to such shares of Common  Stock,  and shall have no other
rights of a  stockholder  with  respect to the RSUs  unless and until the Common
Stock issuable upon conversion of the RSUs has been delivered to Employee.

7.   Compliance with Law and Regulations.

     This Agreement and the obligation of Company to issue and deliver shares of
Common  Stock upon  conversion  of the RSUs  shall be subject to all  applicable
federal and state  laws,  rules and  regulations  and to such  approvals  by any
government or regulatory agency as may be required. Moreover, the RSUs shall not
be converted to Common Stock if such conversion  would be contrary to applicable
law.

8.   Adjustment to Common Stock.

     In  the  event  of  any  stock  split,  stock  dividend,  recapitalization,
reorganization,   merger,  consolidation,   combination,   exchange  of  shares,
liquidation, spin-off or other similar change in capitalization or event, or any
distribution  to holders of Common Stock other than a normal cash dividend,  the
number and class of  securities  each RSU shall be  convertible  into under this
Agreement  shall be  appropriately  adjusted  by Company to the extent the Board
shall  determine,  in good  faith,  that such an  adjustment  is  necessary  and
appropriate.  As used in this  Agreement,  "Board" shall mean Company's Board of
Directors.  All references in this Agreement to the "Board" shall mean the Board
or a committee  of the Board to the extent that the Board's  powers or authority
under this Agreement have been delegated to a committee pursuant to the Plan.

9.   Withholding.

     Employee shall pay to Company,  or make provision  satisfactory  to Company
for payment of, any taxes required by law to be withheld in connection with this
Agreement  no later  than each  Grant Date upon  which  Company  grants  RSUs to
Employee. Employee may satisfy such tax obligations by delivering to Company (i)
cash in the form of wire  transfer  or check or (ii)  shares  of  Common  Stock,
including shares retained from this Agreement, valued at their fair market value
as determined  by (or in a manner  approved by) Company in good faith or (iii) a
combination of (i) and (ii). Company may, to the extent permitted by law, deduct
any such tax obligations from any payment of any kind otherwise due to Employee.

10.  Common Stock Reserved.

     Company  shall at all times during the term of this  Agreement  reserve and
keep  available  such number of shares of Common Stock as will be  sufficient to
satisfy the requirements of this Agreement.

11.  Securities Act Exemption.

     The RSUs have not been  registered  under the  Securities  Act of 1933,  as
amended (the "Securities Act").  Employee hereby confirms that Employee has been
informed that any RSUs acquired  hereunder are restricted  securities  under the
Securities Act and may not be resold or  transferred  unless such RSUs are first
registered  under  applicable  securities  laws  or  unless  an  exemption  from
registration  is  available.  Company shall in no event be obligated to register
any securities  pursuant to the Securities Act or to take any other  affirmative
action in order to cause the issuance or transfer of RSUs  acquired  pursuant to
this  Agreement  to  comply  with  any  law or  regulation  of any  governmental
authority.

12.  Delaware Law to Govern.

     This Agreement  shall be construed and  administered in accordance with and
governed  by the laws of the State of  Delaware  (without  giving  effect to any
conflict or choice of laws  provisions  thereof that would cause the application
of the domestic substantive laws of any other jurisdiction).

13.  Notices.

     Any  notice  hereunder  to  Company  shall be  addressed  to Company at its
principal business office, 234 Ballardvale Street, Wilmington, MA 01887, and any
notice  hereunder  to  Employee  shall be sent to the address  reflected  on the
payroll records of Company, subject to the right of either party to designate at
any time hereafter in writing some other address.

14.  Amendment of Agreement.

     Company  may amend,  modify or  terminate  this  Agreement,  provided  that
Employee's  consent to such action shall be required  unless Company  determines
that the action,  taking into account any related  action,  would not materially
and adversely affect Employee.

15.  Successors and Assigns; No Third Party Beneficiaries.

     Except as otherwise  expressly provided herein, the provisions hereof shall
inure to the benefit of, and be binding upon, the  successors,  assigns,  heirs,
executors and  administrators  of the parties  hereto.  There are no third party
beneficiaries of this Agreement.

16.  Provisions of the Plan.

     This  Agreement is subject to the  provisions  of the Plan, a copy of which
Employee hereby acknowledges receiving with this Agreement.

17.  Entire Agreement.

     This Agreement and the Plan  constitute  the full and entire  understanding
and  agreement  of the parties  with regard to the RSUs and  supersede  in their
entirety  all other prior  agreements,  whether  oral or written,  with  respect
thereto.

18.  Severability;   Titles  and   Subtitles;   Gender;   Singular  and  Plural;
     Counterparts; Facsimile.

     (a) In case any provision of this  Agreement  shall be invalid,  illegal or
unenforceable,  the  validity,  legality  and  enforceability  of the  remaining
provisions  of this  Agreement  shall  not in any way be  affected  or  impaired
thereby.

     (b) The titles of the sections and  subsections  of this  Agreement are for
convenience  of reference  only and are not to be considered in construing  this
Agreement.

     (c) The use of any gender in this Agreement  shall be deemed to include the
other genders,  and the use of the singular in this Agreement shall be deemed to
include the plural (and vice versa), wherever appropriate.

     (d) This Agreement may be executed in any number of  counterparts,  each of
which shall be an original, but all of which together constitute one instrument.

     (e)  Counterparts of this Agreement (or applicable  signature pages hereof)
that are manually signed and delivered by facsimile transmission shall be deemed
to constitute  signed  original  counterparts  hereof and shall bind the parties
signing and delivering in such manner.

     IN WITNESS  WHEREOF,  the parties have executed this  Agreement as a sealed
instrument as of the Effective Date.

EMPLOYEE:                              BEACON POWER CORPORATION

By:                                    By:
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         Signature                             Signature

Name:                                  Name:
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Address:                               Title:
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