As independent registered public accountants, we hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of our report dated March 20, 2009, relating to the consolidated financial statements of American DG Energy Inc. which appear in the Company’s Annual Report on Form 10-K for the year ended December 31, 2008 and to the reference to us under the heading “Experts” in the prospectus which is part of this Registration Statement.