<PAGE>

                                                                   EXHIBIT 10.1

                        [SATCON LETTERHEAD APPEARS HERE]

March 22, 2000


Mr. Sean Moran
3 Creek Drive
Norfolk, MA  01801


Dear Sean:

         Please be advised that if within one year of the occurrence of a Change
in Control Event your employment with SatCon Technology Corporation (the
"Company") is terminated by the Company and there occurs an Involuntary
Termination of your employment, the Company shall continue to pay your salary as
in effect on the date of termination until the date one year after the date of
termination ("Continuation Payments"); PROVIDED, HOWEVER, as a condition to your
receipt of any Continuation Payments you execute and deliver a general release
to the Company in a form reasonably acceptable to the Company within 60 days of
your termination.

         For purposes of this letter, Change in Control Event and Involuntary
Termination shall be defined as follows:

         (a) A "Change in Control Event" shall mean:

              (i) the acquisition by an individual, entity or group (within the
                  meaning of Section 13(d)(3) or 14(d)(2) of the Securities
                  Exchange Act of 1934, as amended (the "Exchange Act")) (a
                  "Person") of beneficial ownership of any capital stock of the
                  Company if, after such acquisition, such Person beneficially
                  owns (within the meaning of Rule 13d-3 promulgated under the
                  Exchange Act) 50% or more of either (x) the then-outstanding
                  shares of common stock of the Company (the "Outstanding
                  Company Common Stock") or (y) the combined voting power of the
                  then-outstanding securities of the Company entitled to vote
                  generally in the election of directors (the "Outstanding
                  Company Voting Securities"); PROVIDED, HOWEVER, that for
                  purposes of this subsection (i), the following acquisitions
                  shall not constitute a Change in Control Event: (A) any
                  acquisition directly from the Company (excluding an
                  acquisition pursuant to the exercise, conversion or exchange
                  of any security exercisable for, convertible into or
                  exchangeable for common stock or voting securities of the
                  Company, unless the Person exercising, converting or
                  exchanging such security acquired such security directly from
                  the Company or an underwriter or agent of the Company), (B)
                  any acquisition by any employee benefit plan (or related
                  trust) sponsored or maintained by the Company or any
                  corporation controlled by the Company, or (C) any acquisition
                  by any corporation pursuant to a Business Combination (as


<PAGE>


                  defined below) which complies with clauses (x) and (y) of
                  subsection (iii) of this definition; or

              (ii)such time as the Continuing Directors (as defined below) do
                  not constitute a majority of the Board (or, if applicable, the
                  Board of Directors of a successor corporation to the Company),
                  where the term "Continuing Director" means at any date a
                  member of the Board (x) who was a member of the Board on the
                  date of this letter or (y) who was nominated or elected
                  subsequent to such date by at least a majority of the
                  directors who were Continuing Directors at the time of such
                  nomination or election or whose election to the Board was
                  recommended or endorsed by at least a majority of the
                  directors who were Continuing Directors at the time of such
                  nomination or election; PROVIDED, HOWEVER, that there shall be
                  excluded from this clause (y) any individual whose initial
                  assumption of office occurred as a result of an actual or
                  threatened election contest with respect to the election or
                  removal of directors or other actual or threatened
                  solicitation of proxies or consents, by or on behalf of a
                  person other than the Board; or

             (iii)the consummation of a merger, consolidation, reorganization,
                  recapitalization or statutory share exchange involving the
                  Company or a sale or other disposition of all or substantially
                  all of the assets of the Company (a "Business Combination"),
                  unless, immediately following such Business Combination, each
                  of the following two conditions is satisfied: (x) all or
                  substantially all of the individuals and entities who were the
                  beneficial owners of the Outstanding Company Common Stock and
                  Outstanding Company Voting Securities immediately prior to
                  such Business Combination beneficially own, directly or
                  indirectly, more than 50% of the then-outstanding shares of
                  common stock and the combined voting power of the
                  then-outstanding securities entitled to vote generally in the
                  election of directors, respectively, of the resulting or
                  acquiring corporation in such Business Combination (which
                  shall include, without limitation, a corporation which as a
                  result of such transaction owns the Company or substantially
                  all of the Company's assets either directly or through one or
                  more subsidiaries) (such resulting or acquiring corporation is
                  referred to herein as the "Acquiring Corporation") in
                  substantially the same proportions as their ownership of the
                  Outstanding Company Common Stock and Outstanding Company
                  Voting Securities, respectively, immediately prior to such
                  Business Combination and (y) no Person (excluding the
                  Acquiring Corporation or any employee benefit plan (or related
                  trust) maintained or sponsored by the Company or by the
                  Acquiring Corporation) beneficially owns, directly or
                  indirectly, 50% or more of the then-outstanding shares of
                  common stock of the Acquiring Corporation, or of the combined
                  voting power of the then-outstanding securities of such
                  corporation entitled to vote generally in the election of


<PAGE>


              directors (except to the extent that such ownership existed
              prior to the Business Combination).

         (b)  "Involuntary Termination" shall include (i) a material adverse
              change in the authority, duties or compensation of Sean Moran
              without your prior consent or (ii) the relocation of your place of
              work more than 100 miles from the Company's executive offices at
              the time of the Change of Control Event.

         If this is in accordance with your understanding, please indicate your
agreement by signing below. This letter shall be void if it is not countersigned
by you and returned to the Company within 10 days of the date of this letter.


                                                     Sincerely,


                                                     /s/ MICHAEL C. TURMELLE
                                                     --------------------------
                                                     Michael Turmelle
                                                     Chief Operating Officer


/s/ SEAN MORAN
--------------------
Sean Moran



3/22/2000
--------------------
Date