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                                                                 Exhibit 10.40

[LETTERHEAD OF J.P. TURNER & COMPANY, L.L.C.]

                                                               August 20, 2002

Mr. David Eisenhaure
Chairman, President, and CEO
Satcon Technology Corporation
161 First Street
Cambridge, MA 02142
tel: (617) 661-0540
fax: (617) 661-3373

         RE: INVESTMENT BANKING AGREEMENT WITH J. P. TURNER & COMPANY, LLC

Dear Mr. Eisenhaure,

         This letter (the "AGREEMENT") shall confirm the engagement of J.P.
Turner & Company, LLC ("TURNER") by Satcon Technology Corporation [NASDAQNM:
SATC] (the "COMPANY") for purposes of providing, on a non-exclusive basis,
investor awareness and business advisory services as set forth below in
consideration for the fees and compensation described hereinafter. The Agreement
shall be effective as of the date set forth above.

         The Company agrees to provide Turner such information, historical
financial data, business plans, due diligence documentation, and other
information (collectively the "INFORMATION") in the possession of the Company or
its agents that the parties may reasonably agree is required in order for Turner
to perform the Services (as hereinafter defined) set forth herein. The
Information provided by the Company to Turner shall be true, complete, accurate
and current in all respects and shall not set forth any untrue statements nor
omit any fact required or necessary to make the Information provided not
misleading. The Company acknowledges that Turner may rely on the accuracy and
completeness of all Information provided by the Company without independent
verification. The Company authorizes Turner to use such Information in
connection with its performance of the Services. Turner shall use its
commercially reasonable best efforts to preserve the confidentiality of
Information expressly designated as confidential by the Company.

         Turner will use its best efforts to furnish ongoing investor awareness
and business advisory services (the "SERVICES") as the Company may from time to
time reasonably request. The Services may include, without limitation, the
following: preparation and assistance with investor presentations; introduction
to capital conferences; and introductions to broker dealers, research analysts,
and investment companies that Turner believes to be in the best interest of the
Company.

    Turner represents and warrants that (i) it is a securities broker-dealer
duly licensed and registered pursuant to federal and state securities laws rules
and regulations; (ii) it is qualified and has the authority and ability to
provide the services contemplated in this Agreement; and (iii) it is a member in
good standing with the NASD and is in good standing with all states within which
it is registered to conduct securities business.


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Technology Corporation
Investment Banking Agreement
08/20/02
Page 2 of 7

         The term of this Agreement shall be 12 months from the effective date
of this Agreement (the "TERM"). In the event that the Company desires to
terminate this Agreement prior to the expiration date, it shall provide Turner
with at least sixty (60) days prior written notice of its intention to terminate
this Agreement and this Agreement shall so terminate following the expiration of
this sixty (60) day period (the "TERMINATION DATE"), without any further
responsibility for either party; provided, however, that Turner shall be
entitled to receive all accrued compensation, including any unpaid cash
compensation and all vested Warrants (as set forth below), and un-reimbursed
expenses, if any, outstanding as of the Termination Date.

         In consideration for the services described herein, the Company shall
pay to Turner a monthly advisory fee of seven thousand five hundred dollars ($7,
500) per month (the "MONTHLY ADVISORY FEE"). The first month advisory fee shall
be paid to Turner upon the execution of this Agreement and continuing each month
for the length of the Agreement. The Monthly Advisory Fee shall be earned and
payable each month and may not be deferred by the Company unless the Company
submits a written request to the Turner and Turner approves such request in
writing. Any fees, which Turner agrees to defer, shall accumulate interest at a
rate of 1% per month on the aggregate balance of deferred Monthly Advisory Fees.
The Monthly Advisory Fee shall be directed to Turner in accordance with the
following wiring instructions:

                  Bank:                 Wachovia Bank of Georgia
                  Phone:                404-995-8740
                  Fax:                  404-995-8755
                  Address:              4465 Buckhead Loop, Atlanta, GA  30326
                  ABA Routing #:        061-000-010
                  Account Name:         J.P. Turner & Company, L.L.C.
                  Account #:            186-834-16

         Simultaneously with the execution of this Agreement, the Company shall
issue and deliver to Turner a common stock purchase warrant (the "INVESTMENT
BANKING WARRANT") for the purchase of two hundred fifty thousand (250,000)
shares of the Company's common stock. The Investment Banking Warrant shall have
an exercise price of $1.75 per share and upon issuance, be fully paid,
non-assessable, and free of any restrictions on transfer, but for those
restrictions that are the result of state or federal securities law. The Warrant
shall "vest" in favor of Turner in accordance with the Vesting Schedule attached
hereto as Schedule A. Notwithstanding the foregoing, the Warrant shall
immediately and completely vest in favor of Turner, and shall become immediately
exercisable, in the event of the sale of the Company (or substantially all of
the assets thereof) or the acquisition (or merger) transaction of the Company by
or into another entity. The Warrant shall be issued to Turner in the form of a
warrant agreement (the "WARRANT AGREEMENT"), which shall be in form and content
reasonably satisfactory to Turner and its counsel. The Warrant Agreement shall
provide for, among other provisions, the above terms and the following:

              (i)  Turner may exercise the Warrant at any time after signing the
                   Warrant Agreement. The Warrant shall expire three (3) years
                   from the date that the Warrant Agreement is issued.


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Technology Corporation
Investment Banking Agreement
08/20/02
Page 3 of 7

              (ii) anti-dilution provisions for stock dividends, splits,
                   mergers, sale of substantially all of the Company's assets,
                   except for sale of stock pursuant to the Company's Stock
                   Option Plan(s).

             (iii) in lieu of any cash payment required by Turner in connection
                   with the exercise of the Warrant, the holder(s) of the
                   Warrant shall have the right at any time and from time to
                   time, to exercise the Warrant in full or in part by
                   surrendering the Warrant Agreement as payment of the
                   aggregated Strike Price. The number of shares of Underlying
                   Common Stock to be issued upon exercise shall be determined
                   by multiplying the number of the shares of common stock
                   within the Warrant to be exercised by an amount equal to the
                   market price per share less the Strike Price, and then
                   dividing the product thereof by the market price per share.
                   Solely for the purposes of this paragraph, market price shall
                   be calculated as the average of the market prices for each of
                   the five (5) trading days preceding the date notice is given
                   that the holder(s) intend(s) to exercise the Warrant.

              (iv) the Company shall reserve, and at all times have available, a
                   sufficient number of shares of its common stock to be issued
                   upon the exercise of the Warrant. Furthermore, the Company
                   shall accept, and shall so instruct its transfer agent to
                   accept, an appropriate Rule 144 opinion letter from any
                   qualified securities attorney (not just an opinion from the
                   Company's counsel) representing Turner or any of its
                   employees or agents that are holders of the Warrant.

              (v)  the Company shall, subject to the conditions listed below,
                   grant "piggy back" registration rights, at the Company's
                   expense, to include the shares of the Underlying Common Stock
                   in any registration statement (except for Form S-4 or S-8
                   filings, or any equivalent thereto) filed by the Company
                   under the Securities Act of 1933 relating to an underwriting
                   of the sale of shares of common stock or other security of
                   the Company, subject to customary and reasonable underwriter
                   imposed lock-up requirements.

The Investment Banking Warrant shall be assigned to J.P. Turner & Company,
L.L.C. and mailed to the following address:

           J.P. Turner & Company, L.L.C.
           Attention: Patrick J. Power, Managing Director or Investment Banking
           3340 Peachtree Road
           Suite 2300
           Atlanta, GA 30326
           Phone: 404-479-8300
           Fax: 404-479-8345


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Technology Corporation
Investment Banking Agreement
08/20/02
Page 4 of 7

         During the Term of this Agreement the Company covenants, promises and
agrees that:

              (a)  Company shall immediately notify Turner if it is contacted by
                   NASDAQ for failing to maintain certain listing requirements
                   or any other reason.

              (b)  Company shall furnish Turner with copies of its annual,
                   quarterly and proxy filings with the SEC, within thirty (30)
                   days of the Company's filing thereof.

              (c)  Company shall furnish Turner all press releases and any
                   copies of any communication to the general public and its
                   shareholders.

              (d)  Company shall immediately notify Turner if it is the subject
                   of any investigation or material litigation.


              (e)  At least two (2) business days prior to the dissemination of
                   any public announcement regarding this Agreement, including
                   the fact of its existence, the Company shall submit to
                   Turner, for its review and comment, the proposed public
                   announcement. Turner shall thereafter have two (2) business
                   days within which to submit its proposed amendments to the
                   public announcement for inclusion therein. The proposed
                   amendments shall be incorporated in the final version to be
                   disseminated by the Company, unless, in the reasonable
                   judgment of counsel to the Company, such amendments should
                   not be incorporated.

         Any dispute, controversy or claim arising between the Company and
Turner arising out of or related to this Agreement or breach thereof, shall be
settled by arbitration, which shall be conducted in accordance with the rules of
the American Arbitration Association then in effect and conducted in the County
of Suffolk in the Commonwealth of Massachusetts. Any award made by arbitrators
shall be binding and conclusive for all purposes thereof, may include injunctive
relief, as well as orders for specific performance and may be entered as a final
judgment in any court of competent jurisdiction. No arbitration arising out of
or relating to this Agreement shall include, by consolidation or joinder or in
any other manner, parties other than the Company or Turner and other persons
substantially involved in common questions of fact or law whose presence is
required if complete relief is to be afforded in arbitration. The cost and
expenses of such arbitration shall be borne in accordance with the determination
of the arbitrators and may include reasonable attorneys fees. Each party hereby
further agrees that service of process may be made upon it by registered or
certified mail or personal service at the address provided for herein.

         The Company shall reimburse Turner for all expenses which are
pre-approved by the Company, including, without limitation, acceptable travel
and lodging, printing, legal, and mailing cost that Turner may incur in
performance of the Services under this Agreement. Turner shall submit expense
statements to the Company from time to time and the Company shall reimburse such
expenses promptly thereafter.


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Technology Corporation
Investment Banking Agreement
08/20/02
Page 5 of 7

         The Company shall indemnify and hold harmless Turner and its directors,
officers, employees, agents, attorneys and assigns from and against any and all
losses, claims, costs, damages or liabilities (including the reasonable fees and
expenses of legal counsel) to which any of them may become subject in connection
with the investigation, defense or settlement of any actions or claims caused by
the Company's misstatement of a material fact or omission of a material fact
required to make any statement not misleading. Turner shall indemnify and hold
harmless the Company and the respective directors, officers, agents and
employees of the Company (the "COMPANY PARTIES") from and against all losses,
claims, damages, liabilities and expenses that result from Turner's malfeasance,
or gross negligence in the performance of Turner's duties hereunder.

         The Company acknowledges that Turner has made no guarantees that its
performance hereunder will achieve any particular result with respect to the
Company's business, stock price, trading volume, market capitalization or
otherwise.

         All notices hereunder shall be in writing and shall be validly given,
made or served if in writing and delivered in person or when received by
facsimile transmission, or five days after being sent first class certified or
registered mail, postage prepaid, or one day after being sent by nationally
recognized overnight carrier to the party for whom intended at the address set
forth after each parties signatures.

         If any clause or provision of this Agreement is illegal, invalid or
unenforceable under applicable present or future Laws effective during the Term,
the remainder of this Agreement shall not be affected. In lieu of each clause or
provision of this Agreement that is illegal, invalid or unenforceable, there
shall be added as a part of this Agreement a clause or provision as nearly
identical as may be possible and as may be legal, valid and enforceable. In the
event any clause or provision of this Agreement is illegal, invalid or
unenforceable as aforesaid and the effect of such illegality, invalidity or
unenforceability is that either party no longer has the substantial benefit of
its bargain under this Agreement and a clause or provision as nearly identical
as may be possible cannot be added, then, in such event, such party may in its
discretion cancel and terminate this entire Agreement provided such party
exercises such right within a reasonable time after such occurrence.

         The parties agree and acknowledge that they have jointly participated
in the negotiation and drafting of this Agreement and that this Agreement has
been fully reviewed and negotiated by the parties and their respective counsel.
In the event of an ambiguity or question of intent or interpretation arises,
this Agreement shall be construed as if drafted jointly by the parties and no
presumptions or burdens of proof shall arise favoring any party by virtue of the
authorship of any of the provisions of this Agreement.

         This Agreement shall be governed by and construed under the laws of the
Commonwealth of Massachusetts without regard to principals of conflicts of laws
provisions.

         This Agreement may not be modified, amended, supplemented, canceled or
discharged, except by written instrument executed by all parties. No failure to
exercise, and no delay in exercising, any right, power or privilege under this
Agreement shall operate as a waiver, nor shall any single or partial exercise of
any right, power or privilege hereunder preclude the exercise of any other
right, power or privilege. No waiver of any breach of any provision shall be
deemed to be a waiver of any preceding or succeeding breach of the same or any
other provision, nor shall any waiver be implied from any course of dealing


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Technology Corporation
Investment Banking Agreement
08/20/02
Page 6 of 7

between the parties. To be effective, all waivers must be in writing, signed by
both parties. The rights and remedies of the parties under this Agreement are in
addition to all other rights and remedies, at law or equity, that they may have
against each other except as may be specifically limited herein.

         This Agreement contains the entire understanding of the parties in
respect of its subject matter and supersedes all prior agreements and
understandings (oral or written) between or among the parties with respect to
such subject matter. The parties agree that prior drafts of this Agreement shall
not be deemed to provide any evidence as to the meaning of any provision hereof
or the intent of the parties with respect thereto. Any amendment or modification
to the Agreement shall be by written instrument only and must be executed by a
representative, with complete authority, from the Company and Turner.

         This Agreement may be executed in any number of counterparts, each of
which shall be an original but all of which together shall constitute one and
the same instrument. A telecopy signature of any party shall be considered to
have the same binding legal effect as an original signature.

         In the event that any dispute among the parties to this Agreement
should result in litigation, the substantially prevailing party in such dispute
shall be entitled to recover from the losing party all fees, costs and expenses
of enforcing any right of such substantially prevailing party under or with
respect to this Agreement, including without limitation, such reasonable fees
and expenses of attorneys and accountants, which shall include, without
limitation, all fees, costs and expenses of appeals and collection.

         If any provision of this Agreement conflicts with any law, rule or
regulation of any federal, state or self-regulatory organization, including the
Securities and Exchange Commission, the blue-sky laws of any state, the National
Association of Securities Dealers, Inc., or any other governmental authority
having jurisdiction over the activities or services described herein, then in
that event, the Company and Turner shall amend this Agreement to bring any
affected provision into compliance with such regulations.


                            [SIGNATURE PAGE FOLLOWS]


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Technology Corporation
Investment Banking Agreement
08/20/02
Page 7 of 7

         If the foregoing is in accordance with your understanding, kindly
confirm your acceptance and agreement by signing and returning the enclosed
duplicate of this Agreement that will thereupon constitute an agreement between
us.

                                          Yours very truly,


                                          Patrick J. Power
                                          Managing Director, Investment Banking
                                          J. P. Turner & Company, LLC




Accepted and approved this ______ day of ________________, 2002.



By:
                  -----------------------------------------------------

Name:             MR. DAVID EISENHAURE
Title:            CHAIRMAN, PRESIDENT, AND CEO
Company:          SATCON TECHNOLOGY CORPORATION
Address:          161 FIRST STREET
                  CAMBRIDGE, MA 02142
Phone:            (617) 661-0540
Facsimile:        (617) 661-3373