REVOLVING LINE OF CREDIT AGREEMENT
(Amended as of February 22, 2010)
This Revolving Line of Credit Agreement (the “Agreement”) is made and entered into in this 17th day of
December, 2009 by and between John Hatsopoulos (“Lender”), residing at 3 Woodcock Lane, Lincoln,
Massachusetts 01773 and American DG Energy Inc., a corporation organized under the laws of Delaware
(“Borrower”), with offices located at 45 First Avenue, Waltham, Massachusetts 02451.
In consideration of the mutual covenants and agreements contained herein, the parties agree as follows:
1. LINE OF CREDIT. During the term hereof, the Lender will from time to time, at the written request of
the Borrower, lend to the Borrower such funds as may from time to time be requested by the Borrower
(the “Credit Line”). The aggregate principal amount of such funds outstanding at any time shall not exceed
Five Million U.S. Dollars ($5,000,000.00) (the “Credit Limit”). At the time of the first advance of funds
under this Agreement, the Borrower shall execute and deliver to Lender the Promissory Note in the form
attached to this Agreement. All sums advanced on the Credit Line or pursuant to the terms of this
Agreement (each an “Advance”) shall become part of the principal of said Promissory Note.
2. INTEREST. All sums advanced pursuant to this Agreement shall bear interest from the date each
Advance is made until paid in full at the Bank Prime Rate as quoted from time to time in the Wall Street
Journal plus one and one half percent (1.5%) per annum (the “Effective Rate”).
3. TERM. The term of this Agreement shall commence as of the date first set forth above and shall
terminate on December 31, 2012 (the “Maturity Date”).
4. PERMITTED USES OF FUNDS. Any funds advanced to the Borrower may be used solely in
connection with the development and installation of current and new energy systems such as cogeneration
systems and chillers and not for general corporate purposes including operati