American DG Energy Directors Elect New Board Member

American DG Energy Inc. (NYSE Amex:ADGE), a leading On Site Utility, offering clean electricity, heat, hot water and cooling solutions to hospitality, healthcare, housing and athletic facilities, today announced that Francis A. Mlynarczyk, Jr., was elected to the Company’s Board of Directors.

Frank Mlynarczyk is a founding member and chief executive officer of Scarsdale Equities LLC, a New York City based FINRA member firm that began business in 2005. From 1993 to 2005 he was chief operating officer of Brimberg & Co., L.P., a registered broker/dealer. Prior to that time he was a private investor subsequent to holding senior positions in portfolio management, securities trading, firm management, and compliance at three registered investment advisors. Mr. Mlynarczyk has a Ph.D. in financial accounting and control, an M.S. in industrial administration, and a B.S. in aeronautical and engineering sciences, all from Purdue University.

“We are excited to have Frank as a new member of our Board of Directors. His knowledge and prior expertise in senior operating positions at various companies, where he demonstrated leadership capability and garnered extensive expertise involving complex financial matters will be a great benefit to our Board of Directors and will help build additional value for our shareholders,” said John N. Hatsopoulos, Chief Executive Officer of American DG Energy.

The board determined that Mr. Mlynarczyk is an independent director and he is not expected to serve on any committees of the Board of Directors of the Company.

About American DG Energy

American DG Energy supplies low-cost energy to its customers through distributed power generating systems. The Company is committed to providing institutional, commercial and small industrial facilities with clean, reliable power, cooling, heat and hot water at lower costs than charged by local utilities – without any capital or start-up costs to the energy user – through its On-Site Utility energy solutions. American DG Energy is headquartered in Waltham, Massachusetts. More information can be found at www.americandg.com.

FORWARD-LOOKING STATEMENTS

This press release contains forward-looking statements under the Private Securities Litigation Reform Act of 1995 that involve a number of risks and uncertainties. Important factors could cause actual results to differ materially from those indicated by such forward-looking statements, as disclosed on the Company’s website and in Securities and Exchange Commission filings. This press release does not constitute an offer to buy or sell securities by the Company, its subsidiaries or any associated party and is meant purely for informational purposes. The statements in this press release are made as of the date of this press release, even if subsequently made available by the Company on its website or otherwise. The Company does not assume any obligation to update the forward-looking statements provided to reflect events that occur or circumstances that exist after the date on which they were made.