EXHIBIT 10.102

                                 PROMISSORY NOTE

Amount:   $161,000.00                                     Date: July 30, 1993

         For value received, I, Donald A. Livingston (the "Maker"), an employee
of Environmental Power Corporation, a Delaware corporation (the "Company"),
hereby promise to pay the Company ON DEMAND the principal amount of One Hundred
Sixty-One Thousand Dollars & 00/100 ($161,000.00) with interest (computed on the
basis of a 360 day year of twelve 30-day months) payable from the date hereof on
the unpaid balance of such principal amount, such interest to be payable
monthly.

         The interest payable on this Note shall track the Applicable Federal
"short-term monthly" Rate as defined in Section 1274(d) of the Internal Revenue
Code of 1954, as amended.

         As security for payments to be made by the Maker pursuant to this Note,
the Company shall retain custody of, and a security interest in, the certificate
or certificates representing 1,150,000 Shares of the Company's Common Stock,
such security interest to lapse at such time as all of the obligations of the
Maker under this Note have been satisfied in full or the Note has been canceled.

         The Company shall have full recourse against the Maker for collection
and payment of the debt evidenced by this Note and may seek personal judgment
against the Maker for payment of this Note.

         All or any part of the principal and accrued interest may be prepaid at
anytime without the payment of any penalty or premium.

         In case any payment herein provided shall not be paid when due, the
Maker further promises to pay all costs at collection, including all attorney's
fees.

         This Note shall be governed by and construed in accordance with the
laws of the State of New Hampshire and shall have the effect of a sealed
instrument.

         The Maker and all endorsers and guarantors of this Note hereby waive
presentment, demand, notice of nonpayment, protest and all other demands and
notices in connection with the delivery, acceptance, performance or enforcement
of the Note.

                                         Maker


                                         /s/ Donald A. Livingston
                                         -----------------------
                                         Donald A. Livingston