Description of Business and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	American DG Energy Inc., or the Company, we, our or us, distributes, owns, operates and maintains clean, on-site energy systems that produce electricity, hot water, heat and cooling. The Company's business model is to own the equipment that it installs at customers' facilities and to sell the energy produced by these systems to its customers on a long-term contractual basis at prices guaranteed to the customer to be below conventional utility rates. The Company calls this business the American DG Energy “On-Site Utility”. The Company has experienced total net losses since inception of approximately $39 million. For the foreseeable future, the Company expects to experience continuing operating losses and negative cash flows from operations as its management executes the current business plan. The Company believes that its existing resources, including cash and cash equivalents and future cash flow from operations, are sufficient to meet the working capital requirements of its existing business for the foreseeable future. However, as the Company continues to grow its business by adding more energy systems, cash requirements will increase, and the Company may need to raise additional capital through debt financings or equity offerings to meet its operating and capital needs. There can be no assurance, however, that the Company will be successful in its fundraising efforts or that additional funds will be available on acceptable terms, if at all. If the Company is unable to raise additional funds in the future it may need to terminate certain employees and adjust its business plans. Financial considerations may cause the Company to modify planned deployment of new energy systems and may decide to suspend installations until it is able to secure additional working capital. The Company will evaluate possible acquisitions of, or investments in, businesses, technologies and products that are complementary to its business; however, the Company is not currently engaged in such discussions.
Basis of Presentation	The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q and Article 8 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments considered necessary for a fair presentation have been included. Operating results for the nine months ended September 30, 2015 are not necessarily indicative of the results that may be expected for the year ended December 31, 2015. The consolidated balance sheet at December 31, 2014 has been derived from the audited consolidated financial statements at that date but does not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. For further information, refer to the consolidated financial statements and footnotes thereto included in American DG Energy Inc.’s annual report on Form 10-K for the year ended December 31, 2014. There have been no significant changes in accounting principles, practices or methods for making estimates. The accompanying unaudited consolidated financial statements include the accounts of the Company and entities in which it has a controlling financial interest. Those entities include the Company's 51.0% owned joint venture, American DG New York, LLC, or ADGNY, and its 48.0% owned subsidiary EuroSite Power Inc., or EuroSite Power. The Company has determined EuroSite Power to be a Variable Interest Entity (VIE) and for which the Company has determined it is the primary beneficiary (see Note 9. "Variable Interest Entity”). The Company’s operations are comprised of one business segment. The Company’s business is selling energy in the form of electricity, heat, hot water and cooling to its customers under long-term sales agreements.