S-3

As filed with the Securities and Exchange Commission on December 23, 2009

Registration No. 333-____________

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM S-3

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

AMERICAN DG ENERGY INC.

(Exact name of registrant as specified in its charter)

Delaware	1711	04-3569304
(State or other jurisdiction of	(Primary Standard Industrial	(I.R.S. Employer
incorporation or organization)	Classification Code Number)	Identification No.)

American DG Energy Inc.

45 First Avenue

Waltham, MA 02451

781-622-1120

(Address, including zip code, and telephone number,

including area code, of registrant’s principal executive offices)

	Copy to:
John N. Hatsopoulos	Edwin L. Miller Jr.
Chief Executive Officer	Sullivan & Worcester LLP
American DG Energy Inc.	One Post Office Square
45 First Avenue	Boston, MA 02109
Waltham, MA 02451	Tel: (617) 338-2800/Fax: (617) 338-2880
(781) 622-1120/Fax: (781) 622-1027
(Name, address, including zip code, and telephone number, including area code, of agent for service)

Approximate date of commencement of proposed sale to the public:

From time to time after this registration statement becomes effective

If the only securities being registered on this form are being offered pursuant to dividend or interest reinvestment plans, check the following box.  ¨

If any of the securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box.  ¨

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  ¨

If this form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. (Check one):

Large accelerated filer: ¨ Accelerated filer: ¨ Non-accelerated filer: ¨ Smaller reporting company: ¨

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be Registered	Amount to be Registered 1	Proposed Maximum Offering Price		Proposed Maximum Aggregate Offering Price		Amount of Registration Fee
Common Stock	8,931,836 shs.	$	2.92	$	26,080,961	$	1,860

1 Estimated solely to calculate the registration fee in accordance with Rule 457 under the Securities Act based on the average of the high and low sales prices of the common stock on the NYSE Amex on December 22, 2009.

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

PROSPECTUS (Subject to Completion)

Dated December 23, 2009

PROSPECTUS

8,931,836 Shares of Common Stock

We are registering for resale pursuant to this prospectus shares of our outstanding common stock, shares issuable upon conversion of outstanding convertible debentures and shares issuable upon exercise of outstanding warrants, other than shares that may be sold without restriction pursuant to Rule 144.

Included in the aggregate number of shares are: 3,548,405 outstanding shares of common stock; 5,321,431 shares issuable upon conversion of outstanding convertible debentures, and 62,000 shares issuable upon exercise of warrants.

Our common stock is traded on the NYSE Amex under the symbol “ADGE”. The last reported sale price of our common stock on December 22, 2009 was $2.96 per share.

The selling stockholders may sell all or a portion of their shares on the NYSE Amex at prices prevailing at the time of sale, or related to the market price at the time of sale, or they may otherwise sell their shares at negotiated prices.

We will not receive any of the proceeds from the offer and sale of the shares. If the warrants related to the shares of common stock offered for sale pursuant to this prospectus are exercised in full, we will receive aggregate proceeds from such exercises of $150,000. We will pay the expenses of this offering.

Our business and an investment in our common stock involve significant risks.  You should refer to the factors described in the section called “Risk Factors” contained in our Annual Report on Form 10-K, page 10, for our 2008 fiscal year that has been incorporated by reference in this prospectus. See page 2 for the reference.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is __________.

TABLE OF CONTENTS

About this Prospectus	2
Special Note Regarding Forward-Looking Statements	2
About the Company	3
Dividend Policy	3
Use of Proceeds	3
Determination of Offering Price and Market Data	3
Selling Stockholders	4
Plan of Distribution	8
Experts	8
Incorporation by Reference	8
Where You Can Find More Information	10

ABOUT THIS PROSPECTUS

In this prospectus, references to the “company,” “we,” “us,” “our,” and “registrant” refer to American DG Energy Inc.

You should rely only on the information contained in this prospectus. We have not, and the selling stockholders have not, authorized anyone to provide you with information that is different. The selling stockholders are offering to sell and seeking offers to buy shares of our common stock only in jurisdictions where offers and sales are permitted. You should assume that the information appearing in this prospectus as well as the information we filed previously with the Securities and Exchange Commission, or SEC, and incorporated herein by reference is accurate only as of the date of the document containing the information.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents incorporated by reference contain forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical fact, included in this prospectus regarding our strategy, future operations, future financial position, future revenues, projected costs, prospects and plans and objectives of management are forward-looking statements. The words “anticipates,” “believes,” “estimates,” “expects,” “intends,” “may,” “plans,” “projects,” “will,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.

We have based these forward-looking statements on our current expectations and projections about future events.  Although we believe that the expectations underlying our forward-looking statements are reasonable, these expectations may prove to be incorrect, and all of these statements are subject to risks and uncertainties. Therefore, you should not place undue reliance on our forward-looking statements. We have included important risks and uncertainties in the cautionary statements included in this prospectus, particularly the section called “Risk Factors” incorporated by reference herein. We believe these risks and uncertainties could cause actual results or events to differ materially from the forward-looking statements that we make. Should one or more of these risks and uncertainties materialize, or should underlying assumptions, projections or expectations prove incorrect, actual results, performance or financial condition may vary materially and adversely from those anticipated, estimated or expected. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, joint ventures or investments we may make. We do not assume any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

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ABOUT THE COMPANY

We distribute and operate on-site cogeneration systems that produce both electricity and heat. Our business is to own the equipment that we install at customers’ facilities and to sell the energy produced by these systems to the customers on a long-term contractual basis. We call this business the American DG Energy “On-Site Utility”.

We offer a range of cogeneration systems that are highly reliable and energy efficient. Our cogeneration systems produce electricity from an internal combustion engine driving a generator, while the heat from the engine and exhaust is recovered and typically used to produce heat and hot water for on-site processes. We also distribute and operate water chiller systems that operate in a similar manner, except that the engine’s power drives a large air-conditioning compressor while recovering heat for hot water. Cogeneration systems reduce the amount of electricity that the customer must purchase from the local utility and produce valuable heat and hot water for the site to use as required.

The company was incorporated as a Delaware corporation on July 24, 2001. American DG Energy operated as a subsidiary of American Distributed Generation Inc. since 2003, along with Tecogen Inc. In December 2005, American DG Energy merged with American Distributed Generation Inc., and the company then changed its name to American DG Energy Inc. Our principal executive offices are located at 45 First Avenue, Waltham, Massachusetts 02451.

DIVIDEND POLICY

We have never declared or paid any cash dividends on shares of our common stock. We currently intend to retain earnings, if any, to fund the development and growth of our business and do not anticipate paying cash dividends in the foreseeable future. Our payment of any future dividends will be at the discretion of our board of directors after taking into account various factors, including our financial condition, operating results, cash needs and growth plans.

USE OF PROCEEDS

We will not receive any of the proceeds from the offer and sale of the shares. If the warrants related to the shares of common stock offered for sale pursuant to this prospectus are exercised in full, we will receive aggregate proceeds from such exercises of $150,000. The funds we will receive from the proceeds of exercises of options related to shares of common stock or rights to purchase shares of common stock pursuant to our private placement will be used for installation of additional energy systems and for general corporate purposes.

DETERMINATION OF OFFERING PRICE AND MARKET DATA

Offering Price

The selling stockholders may sell all or a portion of their shares in the NYSE Amex market at prices prevailing at the time of sale, or related to the market price at the time of sale, or they may otherwise sell their shares at negotiated prices. We cannot determine what the actual offering price will be at the time of sale.

Market

Our common stock started trading on November 8, 2007 on the OTC Bulletin Board, or OTCBB, under the symbol “ADGE”. OTCBB market quotations reflect inter-dealer prices, without retail mark-up, mark-down or commissions and may not necessarily represent actual transactions. During the period from November 8, 2007 to December 31, 2007, the high price was $1.25 and the low price was $0.83 as reported by the OTCBB. The following table sets forth the high and low per share sales prices for our common stock for each of the quarters in the period beginning January 1, 2008 through September 30, 2009 as reported by the OTCBB. On October 19, 2009, the company’s common stock began trading on the NYSE Amex market.

Quarter Ended	High		Low
March 31, 2008	$	1.09	$	0.73
June 30, 2008	$	1.92	$	1.01
September 30, 2008	$	2.05	$	1.35
December 31, 2008	$	2.31	$	1.65
March 31, 2009	$	2.20	$	1.50
June 30, 2009	$	3.25	$	2.45
September 30, 2009	$	3.08	$	2.70

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The closing price of our common stock as reported on the NYSE Amex on December 22, 2009 was $2.96.

Holders

As of November 2, 2009, there were approximately 446 beneficial holders of our common stock.

SELLING STOCKHOLDERS

We are registering for resale pursuant to this prospectus shares of our outstanding common stock, shares issuable upon conversion of outstanding convertible debentures and shares issuable upon conversion or exercise of our outstanding warrants.  Included in the aggregate number of shares are: 3,548,405 outstanding shares of common stock; 5,321,431 shares issuable upon conversion of outstanding convertible debentures, and 62,000 shares issuable upon exercise of warrants.

All of the shares of our common stock offered under this prospectus are being sold by the holders thereof and not by the company. All costs, expenses and fees in connection with the registration of the selling stockholders’ shares will be borne by us. All brokerage commissions, if any, attributable to the sale of shares by selling stockholders will be borne by such holders.

Each selling stockholder may sell all, none or a portion of the shares offered. We cannot estimate the number of shares of common stock that the selling stockholders will sell pursuant to this prospectus.

Beneficial ownership is determined in accordance with the rules of the SEC. These rules generally attribute beneficial ownership of securities to persons who possess sole or shared voting power or investment power with respect to those securities. Except as otherwise indicated, all persons listed below have sole voting and investment power with respect to the shares beneficially owned by them, subject to applicable community property laws. The information is not necessarily indicative of beneficial ownership for any other purpose. With respect to selling stockholders that are entities, the individuals who have voting or investment power over the shares, as indicated, disclaim beneficial ownership of the securities except for their pecuniary interest therein.

Percentage ownership calculations are based on shares beneficially owned and shares outstanding as of December 22, 2009. The following table sets forth certain beneficial ownership information with regard to the selling stockholders both before the offering and after the offering as if each shareholder had separately sold all shares registered.

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	Shares Beneficially Owned							Shares Beneficially Owned
	Prior to Offering					Shares Being		After Offering
Selling stockholder	Number		Percentage			Offered (1)		Number		Percentage
In Holdings Corp. (2)		4,961,905		11.86	%		4,961,905		-		*
Nettlestone Enterprises Limited (3)		3,148,140		8.36	%		676,190		2,471,950		6.56	%
RBC cees Nominees Ltd. B2599/B3957 (4)		357,143		*			357,143		-		*
Charles T. Maxwell (5)		442,858		1.17	%		342,858		100,000		*
Frederick Frank		297,619		*			297,619		-		*
RBC cees Nominees Ltd. B2602/B3923 (6)		250,000		*			250,000		-		*
Global Pensions (7)		250,000		*			250,000		-		*
Berger van Berchem & Co. Ltd. (8)		591,700		1.57	%		250,000		341,700		*
William O. & Sandra M. Flannery, JTWROS		238,095		*			238,095		-		*
Jeremy Benjamin		119,048		*			119,048		-		*
Alexandra O. Bjorklund		119,048		*			119,048		-		*
Ernest Aloi & Catherine Aloi		119,048		*			119,048		-		*
Despina B. Theocharakis		100,000		*			100,000		-		*
F.V.A Mellish		100,000		*			100,000		-		*
Bruno Meier		100,000		*			100,000		-		*
Gundyco In Trust for Hans Schopper (9)		100,000		*			100,000		-		*
Adam C. Schachter (10)		72,024		*			72,024		-		*
Richard Aghababian		59,524		*			59,524		-		*
Bruce Wainer		59,524		*			59,524		-		*
Daniel Barnett (11)		50,000		*			50,000		-		*
Kenneth G. Eisner		50,000		*			50,000		-		*
Edward Miller (12)		65,000		*			40,000		25,000		*
Michael Zuk (13)		37,762		*			37,762		-		*
Edward Crouch		29,762		*			29,762		-		*
Integrated Risk Facilities Holdings, Inc.		23,810		*			23,810		-		*
David J. Talbot		20,000		*			20,000		-		*
John E. Shore Generation Skipping Trust (14)		20,000		*			20,000		-		*
Gary David Cunningham		14,286		*			14,286		-		*
First Clearing LLC FBO Nancy Schachter (15)		12,500		*			12,500		-		*
Hayden IR (16)		12,000		*			12,000		-		*
Jo Ellen Spitz		12,000		*			12,000		-		*
Tina Argyropoulos		10,000		*			10,000		-		*
Edward J. Barber		10,000		*			10,000		-		*
Mehdi Sunderji		7,500		*			7,500		-		*
Anthony Jack Smouha		5,000		*			5,000		-		*
Mark Gerstenfeld		4,000		*			4,000		-		*
Santuccio Ricciardi		1,190		*			1,190		-		*
Total		11,870,486					8,931,836

________________

* Represents beneficial ownership of less than 1% of our outstanding common stock.

1. Shares beneficially owned by our security holders and offered hereby consist of: 3,548,405 outstanding shares of common stock; 5,321,431 shares issuable upon conversion of outstanding convertible debentures, and 62,000 shares issuable upon exercise of warrants.

2. Includes: (a) 795,238 shares of common stock, par value $0.001 per share directly held by In Holdings Corp.; and (b) 4,166,667 shares of common stock that In Holdings Corp. has the right to acquire pursuant to currently convertible 8% senior debentures. Mr. Konstantinos Samaras exercises sole voting and/or dispositive power with respect to the shares of common stock that In Holdings Corp. holds or has the right to acquire pursuant to currently convertible 8% senior debentures. In Holdings Corp’s address is: Calle 50 No. 2, Edif Universal Planta Baja, Apartado 0816-02580, Republic of Panama.

3. Includes 3,148,140 shares of common stock, par value $0.001 per share held by Nettlestone Enterprises Limited. The address of Nettlestone Enterprises Limited is P.O. Box 665 Roseneath, The Grange, St. Peter Port, Guernsey GY1-3SJ, Channel Islands. Messrs. M.T.R Betley, M.S Heyworth and J.R Plimley are the Directors of the company and may be deemed to exercise voting and/or dispositive power with respect to these shares.

4. Includes 357,143 shares of common stock, par value $0.001 per share purchased on July 24, 2009, held by RBC cees Nominees Ltd. B2599/B3957. The address of RBC cees Nominees Ltd. is 19-21 Broad Street, St. Hellier, Jersey JE1 3PB, Channel Islands. Messrs. Jamie Dean and S.E McArthur-Wareing are the authorized signatories of the company and may be deemed to exercise voting and/or dispositive power with respect to these shares.

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5. Includes: (a) 223,810 shares of common stock par value $0.001 per share; (b) options to purchase 100,000 shares of common stock, exercisable within 60 days of December 23, 2009; and (c) 119,048 shares of common stock pursuant to currently convertible 8% senior debentures.

6. Includes 250,000 shares of common stock, par value $0.001 per share purchased on July 24, 2009, held by RBC cees Nominees Ltd. B2602/B3923. The address of RBC cees Nominees Ltd. is 19-21 Broad Street, St. Hellier, Jersey JE1 3PB, Channel Islands. Messrs. Jamie Dean and S.E McArthur-Wareing are the authorized signatories of the company and may be deemed to exercise voting and/or dispositive power with respect to these shares.

7. Includes 250,000 shares of common stock, par value $0.001 per share purchased on July 24, 2009, held by Global Pensions. The address of Global Pensions c/o London Capital Asset Management is 4 Triton Square, Regent’s Place, London NW1 3HG, United Kingdom for the benefit of Mr. Costas Kaplanis. The Directors of Global Pensions are the London and Capital Satellite Board and may be deemed to exercise voting and/or dispositive power with respect to these shares.

8. Includes 591,700 shares of common stock, par value $0.001 per share held by Berger van Berchem & Co. Ltd. The address of Berger van Berchem & Co. Ltd is 26 Rue de la Corraterie, 1204 Geneva, Switzerland. Messrs. Jean-Michel Berger and Nicolas Maitre are the Directors of the company and may be deemed to exercise voting and/or dispositive power with respect to these shares.

9. Includes 100,000 shares of common stock, par value $0.001 per share purchased on July 24, 2009, held by Gundyco In Trust for Hans Schopper AC# 500-01915-27. The address of Gundyco c/o CIBC Wood Gundy is 1, Place Ville Marie, Suite 4125, Montreal QC, H3B 3P9, Canada, for the benefit of Mr. Schopper, for which Mr. Schopper is the sole trustee.

10. Includes: (a) 12,500 shares of common stock, par value $0.001 per share purchased on July 24, 2009, held by Mr. Adam Schachter; and (b) 59,524 shares of common stock that Mr. Adam Schachter & Nicole Schachter have the right to acquire pursuant to currently convertible 8% senior debentures. Mr. Adam Schachter is affiliated with Wells Fargo Advisors. The seller purchased the securities to be resold in the ordinary course of business and at the time of the purchase, the seller had no agreements or understandings directly or indirectly, with any person to distribute the securities.

11. Includes a warrant to purchase 50,000 shares of common stock issued on February 24, 2009, to Daniel Barnett, exercisable within 60 days of December 23, 2009.

12. Includes: (a) 40,000 shares of restricted common stock, granted to Edward Miller, an employee, by permitting him to purchase an aggregate of 40,000 shares of common stock at a price of $0.001 per share; and (b) options to purchase 25,000 shares of common stock, exercisable within 60 days of December 23, 2009.

13. Includes: (a) 8,000 shares of common stock, par value $0.001 per share purchased on July 24, 2009, held by Mr. Michael Zuk; and (b) 29,762 shares of common stock that Mr. Michael Zuk & Gayle Line Zuk have the right to acquire pursuant to currently convertible 8% senior debentures. Mr. Michael Zuk is affiliated with Oppenheimer & Co. and the seller purchased the securities to be resold in the ordinary course of business. The seller purchased the securities to be resold in the ordinary course of business and at the time of the purchase, the seller had no agreements or understandings directly or indirectly, with any person to distribute the securities.

14. Includes 20,000 shares of common stock, par value $0.001 per share purchased on July 24, 2009, held in the John E. Shore Generation Skipping Trust for the benefit of Mr. Shore, for which Mr. Shore is the sole trustee.

15. Includes 12,500 shares of common stock, par value $0.001 per share purchased on July 24, 2009, held in a retirement account by First Clearing LLC FBO Nancy Schachter for the benefit of Mrs. Schachter for which Mrs. Schachter is the sole trustee. Mrs. Schachter is affiliated with Wells Fargo Advisors. The seller purchased the securities to be resold in the ordinary course of business and at the time of the purchase, the seller had no agreements or understandings directly or indirectly, with any person to distribute the securities.

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16. Includes 12,000 warrants issued to Hayden IR on October 1, 2009, based on a vesting schedule, in connection with an investor relations agreement at an exercise price of $2.98. Of those warrants, 4,000 are exercisable within 60 days of December 23, 2009. The warrants carry a cashless exercise provision. Messrs. Peter Seltzberg and Jeff Stanlis are the Directors of the company and may be deemed to exercise voting and/or dispositive power with respect to these shares.

There are no family relationships among members of our Board or our executive officers, other than Dr. George N. Hatsopoulos and Mr. John N. Hatsopoulos who are brothers. Other than Charles T. Maxwell, a director of the company, none of the selling stockholders has held any position or office, or had any other material relationship with the company within the past three years.

ACQUISITION TRANSACTIONS

A description of the transactions pursuant to which the shares registered hereby were acquired by the selling shareholders is as follows.

In April and June 2006, the company sold an aggregate of $6,075,000 principal amount of its 8% convertible debentures to an aggregate of 15 persons. The fair market value of the common stock on the date of each closing of the convertible debentures was $0.70 and the conversion price into shares of common stock was $0.84. Total proceeds were approximately $5,425,000. One of the selling shareholders that participated in this transaction was In Holdings Corp. by purchasing a principal amount of $4,000,000, representing 4,761,905 shares of common stock issuable upon conversion of outstanding convertible debentures. See Exhibit 10.12 for the form of the subscription agreement pursuant to which the convertible debentures were issued. On April 6, 2009, In Holdings Corp. converted a principal amount of $500,000 into 595,238 shares of the company’s common stock at a conversion price of $0.84.

In February 2007, the company raised in a private placement $1,505,000 by selling to Nettlestone Enterprises Limited, a selling shareholder, 2,150,000 shares of common stock at a price of $0.70 per share. The form of the subscription agreement pursuant to which the shares were sold is filed herewith as Exhibit 10.13.

On February 24, 2009, the company sold to Daniel Barnett, one of the selling shareholders, a warrant to purchase shares of common stock for a purchase price of $10,500. The warrant, which expires on February 24, 2012, gives the investor the right but not the obligation to purchase 50,000 shares of the company’s common stock at an exercise price per share of $3.00.  See Exhibit 10.14 for the form of the subscription agreement pursuant to which the warrants were sold.

On April 23, 2009, the company raised $2,260,000 in a private placement of 1,076,190 shares of common stock at a price of $2.10 per share. Included in those shares are 476,190 shares to Nettlestone Enterprises Limited, 23,810 shares to Charles T. Maxwell and 100,000 shares to Despina B. Theocharakis. All investors that participated in the offering are selling shareholders. See Exhibit 10.15 for the form of the subscription agreement pursuant to which the shares were sold.

On July 24, 2009, the company raised $3,492,650 in a private placement of 1,663,167 shares of common stock at a price of $2.10 per share. The company also granted the investors the right to purchase additional shares of common stock at a purchase price of $3.10 per share by December 18, 2009. Included in those shares are 200,000 shares to Nettlestone Enterprises Limited, 607,143 shares to RBC cees Nominees Ltd., 250,000 shares to Global Pensions, 119,048 shares to Jeremy Benjamin, 100,000 shares to F.V.A Mellish, 100,000 shares to Bruno Meier, 100,000 shares to Gundyco In Trust for Hans Schopper, 50,000 shares to Kenneth G. Eisner, 20,000 shares to David J. Talbot, 20,000 shares to John E. Shore Generation Skipping Trust, 14,286 shares to Gary David Cunningham, 12,500 shares to Adam C. Schachter, 12,500 shares to First Clearing LLC FBO Nancy Schachter, 12,000 shares to Jo Ellen Spitz, 10,000 shares to Tina Argyropoulos, 10,000 shares to Edward J. Barber, 8,000 shares to Michael Zuk, 7,500 shares to Mehdi Sunderji, 5,000 shares to Anthony Jack Smouha, 4,000 shares to Mark Gerstenfeld and 1,190 shares to Santuccio Ricciardi. All investors that participated in the offering are selling shareholders.  See Exhibit 10.16 for the form of the subscription agreement pursuant to which the shares were sold.

On October 14, 2009, the company raised $525,000 in a private placement of 250,000 shares of common stock at a price of $2.10 per share. The company also granted the investor the right to purchase additional shares of common stock at a purchase price of $3.10 per share by December 18, 2009. Included in those shares are 250,000 shares to Berger van Berchem & Co. Ltd. The investor that participated in the offering is a selling shareholder. See Exhibit 10.16 for the form of the subscription agreement pursuant to which the shares were sold.

The subscription agreements pursuant to which the foregoing securities were purchased have been filed as exhibits to the Registration Statement, of which this prospectus forms a part.

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PLAN OF DISTRIBUTION

The selling stockholders and any of their pledgees, assignees and successors-in-interest may, from time to time, sell any or all of their shares of common stock covered by this prospectus at prevailing market prices on the NYSE Amex or at privately negotiated prices. We will pay the expenses incurred to register the shares being offered by the selling stockholders for resale, but the selling stockholders will pay any underwriting discounts and brokerage commissions associated with these sales. Any commission or discount will be negotiated immediately prior to the sale with the broker-dealer or agent. The selling stockholders may use any one or more of the following methods when selling shares:

· ordinary brokerage transactions and transactions in which the broker-dealer solicits purchasers;

· block trades in which the broker-dealer will attempt to sell the shares as agent but may position and resell a portion of the block as principal to facilitate the transaction;

· purchases by a broker-dealer as principal and resale by the broker-dealer for its account;

· privately negotiated transactions; and

· a combination of any such methods of sale.

In addition, any shares that qualify for sale under Rule 144 may be sold under Rule 144 rather than through this prospectus. Shares that qualify for unrestricted sale under Rule 144 may not be sold pursuant to this prospectus.

In offering the shares covered by this prospectus, the selling stockholders and any broker-dealers who execute sales for the selling stockholders may be deemed to be an “underwriter” within the meaning of the Securities Act in connection with such sales. Any profits realized by the selling stockholders and the compensation of any broker-dealer may be deemed to be underwriting discounts and commissions.

Transfer Agent

Our transfer agent is Continental Stock Transfer & Trust Company, 17 Battery Place, New York, NY 10004-1123; telephone: 212-509-4000.

EXPERTS

The financial statements of American DG Energy Inc. as of December 31, 2008 and 2007, and for each of the two years in the period ended December 31, 2008, included in our Annual Report on Form 10-K for the year ended December 31, 2008 incorporated by reference in this registration statement have been so incorporated in reliance on the report of Caturano and Company, P.C. (formerly known as Vitale, Caturano & Company, P.C.), independent registered public accountants, given on the authority of said firm as experts in auditing and accounting.

INCORPORATION OF DOCUMENTS BY REFERENCE

The SEC requires us to “incorporate by reference” into this prospectus information that we file with the SEC in other documents. This means that we can disclose important information to you by referring you to other documents that contain that information. The information we incorporate by reference is considered to be part of this prospectus. Information contained in this prospectus and information that we file with the SEC in the future and that we incorporate by reference in this prospectus automatically updates and supersedes previously filed information. We incorporate by reference the documents listed below and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus and prior to the sale of all the shares covered by this prospectus.

· The company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2008, filed with the Commission on March 20, 2009 (File No. 000-52294).

· The company’s Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2009, filed with the Commission on May 14, 2009 (File No. 000-52294).

· The company’s Quarterly Report on Form 10-Q for the fiscal quarter ended June 30, 2009, filed with the Commission on August 14, 2009 (File No. 000-52294).

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· The Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2009, filed with the Commission on November 12, 2009 (File No. 001-34493).

· The company’s current report on Form 8-K filed with the Commission on February 26, 2009 (File No. 000-52294).

· The company’s current report on Form 8-K filed with the Commission on March 4, 2009 (File No. 000-52294).

· The company’s current report on Form 8-K filed with the Commission on April 27, 2009 (File No. 000-52294).

· The company’s current report on Form 8-K filed with the Commission on May 14, 2009 (File No. 000-52294).

· The company’s current report on Form 8-K filed with the Commission on July 27, 2009 (File No. 000-52294).

· The company’s current report on Form 8-K filed with the Commission on August 12, 2009 (File No. 000-52294).

· The company’s current report on Form 8-K filed with the Commission on September 2, 2009 (File No. 000-52294).

· The company’s current report on Form 8-K filed with the Commission on November 12, 2009 (File No. 001-34493).

· The company’s current report on Form 8-K filed with the Commission on December 9, 2009 (File No. 001-34493).

· The company’s current report on Form 8-K filed with the Commission on December 17, 2009 (File No. 001-34493).

· The description of the Common Stock set forth in the company’s registration statement on Form 10-SB filed with the SEC under the Securities Exchange Act of 1934, or the Exchange Act, including any amendments or reports filed for the purpose of updating such description (File No. 000-52294).

· The company’s Proxy Statement for the company’s 2009 Annual Meeting of Stockholders, filed with the Commission on April 29, 2009.

· The company’s Information Statement on Schedule 14C, filed with the Commission on September 8, 2009, including any amendments or reports filed for the purpose of updating such description (File No. 001-34493).

· The company’s Registration of Securities Form 8-A filed with the Commission on October 15, 2009 (File No. 001-34493).

A statement contained in a document incorporated by reference into this prospectus shall be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus, any prospectus supplement or in any other subsequently filed document which is also incorporated in this prospectus modifies or replaces such statement. Any statements so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus.

You may request a copy of these documents, which will be provided to you at no cost, by writing or telephoning us using the following contact information: Anthony S. Loumidis, Chief Financial Officer, American DG Energy Inc., 45 First Avenue, Waltham, MA 02451, Phone: (781) 622-1117.

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WHERE YOU CAN FIND MORE INFORMATION

We are subject to the information reporting requirements of the Exchange Act, and accordingly we file annual, quarterly and current reports, proxy statements and other information with the SEC. Members of the public may read and copy any materials we file with the SEC at the SEC’s Public Reference Room located at 100 F Street, N.E., Washington, DC 20549. Information on the operation of the Public Reference Room may be obtained by calling the SEC at 1-800-SEC-0330.

In addition, we are required to file electronic versions of these materials with the SEC through the SEC’s database system called EDGAR. Copies of this registration statement and its exhibits, as well as of our annual reports, quarterly reports, proxy statements and other filings may be examined without charge by accessing the EDGAR database at www.sec.gov and on our own website at www.americandg.com. Our website is not a part of this prospectus.

We will provide without charge to each person, including any beneficial owner, to whom this prospectus is delivered, upon written or oral request of such person, a copy of any or all of the documents incorporated by reference in this prospectus. Exhibits to the filings will not be sent, however, unless those exhibits have been specifically incorporated by reference in this prospectus.

Requests for such documents should be addressed in writing or by telephone to: Anthony S. Loumidis, Chief Financial Officer, American DG Energy Inc., 45 First Avenue, Waltham, MA 02451, Phone: (781) 622-1117.

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PART II

INFORMATION NOT REQUIRED IN THE PROSPECTUS

Item 14.  Other Expenses of Issuance and Distribution.

The following table summarizes the estimated expenses, other than underwriting commissions that we will incur in connection with this offering.

	Amount
Securities and Exchange Commission registration fee	$	1,860
Legal fees and expenses		5,500
Accounting fees and expenses		1,500
Miscellaneous		1,140
Total	$	10,000

Item 15. Indemnification of Directors and Officers.

Section 102 of the Delaware General Corporation Law allows a corporation to eliminate the personal liability of directors of a corporation to the corporation or its stockholders for monetary damages for a breach of fiduciary duty as a director, except where the director breached his duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of a dividend or approved a stock repurchase in violation of Delaware corporate law or obtained an improper personal benefit. We have included such a provision in our Restated Certificate of Incorporation.

Section 145 of the Delaware General Corporation Law provides that a corporation has the power to indemnify a director, officer, employee or agent of the corporation and certain other persons serving at the request of the corporation in related capacities against amounts paid and expenses incurred in connection with an action or proceeding to which he is or is threatened to be made a party by reason of such position, if such person shall have acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation, and, in any criminal proceeding, if such person had no reasonable cause to believe his conduct was unlawful; provided that, in the case of actions brought by or in the right of the corporation, no indemnification shall be made with respect to any matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the adjudicating court determines that such indemnification is proper under the circumstances.

Our charter includes a provision that eliminates the personal liability of its directors for monetary damages for breach of fiduciary duty as a director, except for liability:

· for any breach of the director’s duty of loyalty to the company or its stockholders;

· for acts or omissions not in good faith or that involve intentional misconduct or a knowing violation of law;

· under section 174 of the Delaware General Corporation Law regarding unlawful dividends and stock purchases; or

· for any transaction from which the director derived an improper personal benefit.

Our Restated Certificate of Incorporation also provides that:

· we must indemnify our directors and officers to the fullest extent permitted by Delaware law;

· we may, to the extent authorized from time to time by our Board of Directors, indemnify our other employees and agents to the same extent that we indemnified our officers and directors; and

· in the event we do not assume the defense in a legal proceeding, we must advance expenses, as incurred, to our directors and executive officers in connection with a legal proceeding to the fullest extent permitted by Delaware law.

The indemnification provisions contained in our Restated Certificate of Incorporation and Amended and Restated Bylaws are not exclusive of any other rights to which a person may be entitled by law, agreement, vote of stockholders or disinterested directors or otherwise.

In addition, we maintain insurance on behalf of our directors and executive officers insuring them against any liability asserted against them in their capacities as directors or officers or arising out of such status.

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Item 16. Exhibits and Financial Statement Schedules

(a)          Exhibits.

Exhibit
Number	Description
3.1#	Certificate of Incorporation, as amended and restated December 9, 2009.
3.2#	By-laws, as amended and restated August 31, 2009.
4.1	Form of Warrant (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
4.2	Warrant to Purchase Shares of Common Stock dated February 24, 2009 (incorporated by reference from the registrant’s current report on Form 8-K, filed with the SEC on February 26, 2009).
5.1#	Opinion of Sullivan & Worcester LLP dated December 23, 2009.
10.1#	Audit Committee Charter, as amended October 13, 2009.
10.2	Compensation Committee Charter (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
10.3#	Nominating and Governance Committee Charter dated August 31, 2009.
10.4	American Distributed Generation Inc. 2001 Stock Incentive Plan (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
10.5	2005 Stock Incentive Plan (incorporated by reference from our definitive proxy statement for the 2008 Annual Meeting of shareholders originally filed with the SEC on April 29, 2008).
10.6	Facilities, Support Services and Business Agreement with Tecogen Inc. (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 22, 2006. Confidential treatment has been granted for portions of this document. The confidential portions have been omitted and have been filed separately, on a confidential basis, with the SEC).
10.7	Amendment to Facilities, Support Services and Business Agreement with Tecogen Inc. dated April 1, 2008 (incorporated by reference from the registrant’s Form 10-Q, filed with the SEC on May 14, 2008, for the quarter ended March 31, 2008).
10.8	Amendment No. 2 to Facilities, Support Services and Business Agreement with Tecogen Inc. dated May 15, 2008 (incorporated by reference from the registrant’s Form 10-K, originally filed, filed with the SEC on March 20, 2009).
10.9	Amendment No. 3 to Facilities, Support Services and Business Agreement with Tecogen Inc. dated January 2, 2009 (incorporated by reference from the registrant’s Form 10-K, originally filed, filed with the SEC on March 20, 2009).
10.10	Operating Agreement of American DG New York LLC (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 22, 2006).
10.11	Form of Energy Purchase Agreement (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
10.12	Form of 8% Senior Convertible Debenture Due 2011 (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
10.13#	Form of Subscription Agreement for private placement of common stock for American DG Energy Inc.
10.14	Form of Warrant to purchase shares of common stock, dated February 24, 2009, entered into between the company and Daniel Barnett (incorporated by reference from the registrant’s current Form 8-K, originally filed with the SEC on February 26, 2009).
10.15	Form of Subscription Agreement for common stock (incorporated by reference from the registrant’s current Form 8-K, originally filed with the SEC on April 27, 2009).

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10.16	Form of Subscription Agreement for common stock (incorporated by reference from the registrant’s current Form 8-K, originally filed with the SEC on July 27, 2009).
14.1	Code of Business Conduct and Ethics (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
16.1	Letter on change in certifying accountant (incorporated by reference from, the company’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
21.1	List of subsidiaries (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
23.1	Consent of Sullivan & Worcester LLP (included in Exhibit 5.1).
23.2#	Consent of Caturano and Company, P.C.
24.1	Power of Attorney (included on signature page).

#   Filed herewith

(b)          Financial Statement Schedules.  None

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Item 17. Undertakings

(a)   The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

i.             To include any prospectus required by section 10(a)(3) of the Securities Act of 1933;

ii.            To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement;

iii.           To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

Provided, however, that paragraphs (1)(i), (ii) and (iii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the registrant pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial  bona fide  offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4)           That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

i.             If the registrant is relying on Rule 430B:

A. Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

B. Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however,  that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date; or

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ii. If the registrant is subject to Rule 430C, each prospectus filed pursuant to Rule 424(b) as part of a registration statement relating to an offering, other than registration statements relying on Rule 430B or other than prospectuses filed in reliance on Rule 430A, shall be deemed to be part of and included in the registration statement as of the date it is first used after effectiveness.  Provided, however,  that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such first use, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such date of first use.

(5) That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities: The undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(b)   The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c)    The undersigned registrant hereby undertakes to supplement the prospectus, after the expiration of the subscription period, to set forth the results of the subscription offer, the transactions by the underwriters during the subscription period, the amount of unsubscribed securities to be purchased by the underwriters, and the terms of any subsequent reoffering thereof. If any public offering by the underwriters is to be made on terms differing from those set forth on the cover page of the prospectus, a post-effective amendment will be filed to set forth the terms of such offering.

(d)    Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant has authorized this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Waltham, Massachusetts on December 23, 2009.

AMERICAN DG ENERGY INC.

By: /s/ JOHN N. HATSOPOULOS

John N. Hatsopoulos

Chief Executive Officer

POWER OF ATTORNEY AND SIGNATURES

The undersigned officers and directors of the company hereby constitute and appoint John N. Hatsopoulos, Barry J. Sanders and Anthony S. Loumidis, and each of them singly, with full power of substitution, our true and lawful attorneys-in-fact and agents to take any actions to enable the company to comply with the Securities Act, and any rules, regulations and requirements of the SEC, in connection with this registration statement, including the power and authority to sign for us in our names in the capacities indicated below any and all amendments to this registration statement and any other registration statement filed pursuant to the provisions of Rule 462 under the Securities Act

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

Signature	Title	Date
/s/ GEORGE N. HATSOPOULOS	Chairman of the Board	December 23, 2009
George N. Hatsopoulos
/s/ JOHN N. HATSOPOULOS	Chief Executive Officer (Principal Executive Officer)	December 23, 2009
John N. Hatsopoulos
/s/ ANTHONY S. LOUMIDIS	Chief Financial Officer (Principal Financial	December 23, 2009
Anthony S. Loumidis	and Accounting Officer)
/s/ EARL R. LEWIS	Director	December 23, 2009
Earl R. Lewis
/s/ CHARLES T. MAXWELL	Director	December 23, 2009
Charles T. Maxwell
/s/ ALAN D. WEINSTEIN	Director	December 23, 2009
Alan D. Weinstein

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EXHIBIT INDEX

Exhibit
Number	Description
3.1#	Certificate of Incorporation, as amended and restated December 9, 2009.
3.2#	By-laws, as amended and restated August 31, 2009.
4.1	Form of Warrant (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
4.2	Warrant to Purchase Shares of Common Stock dated February 24, 2009 (incorporated by reference from the registrant’s current report on Form 8-K, filed with the SEC on February 26, 2009).
5.1#	Opinion of Sullivan & Worcester LLP dated December 23, 2009.
10.1#	Audit Committee Charter, as amended October 13, 2009.
10.2	Compensation Committee Charter (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
10.3#	Nominating and Governance Committee Charter dated August 31, 2009.
10.4	American Distributed Generation Inc. 2001 Stock Incentive Plan (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
10.5	2005 Stock Incentive Plan (incorporated by reference from our definitive proxy statement for the 2008 Annual Meeting of shareholders originally filed with the SEC on April 29, 2008).
10.6	Facilities, Support Services and Business Agreement with Tecogen Inc. (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 22, 2006. Confidential treatment has been granted for portions of this document. The confidential portions have been omitted and have been filed separately, on a confidential basis, with the SEC).
10.7	Amendment to Facilities, Support Services and Business Agreement with Tecogen Inc. dated April 1, 2008 (incorporated by reference from the registrant’s Form 10-Q, filed with the SEC on May 14, 2008, for the quarter ended March 31, 2008).
10.8	Amendment No. 2 to Facilities, Support Services and Business Agreement with Tecogen Inc. dated May 15, 2008 (incorporated by reference from the registrant’s Form 10-K, originally filed, filed with the SEC on March 20, 2009).
10.9	Amendment No. 3 to Facilities, Support Services and Business Agreement with Tecogen Inc. dated January 2, 2009 (incorporated by reference from the registrant’s Form 10-K, originally filed, filed with the SEC on March 20, 2009).
10.10	Operating Agreement of American DG New York LLC (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 22, 2006).
10.11	Form of Energy Purchase Agreement (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
10.12	Form of 8% Senior Convertible Debenture Due 2011 (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
10.13#	Form of Subscription Agreement for private placement of common stock for American DG Energy Inc.
10.14	Form of Warrant to purchase shares of common stock, dated February 24, 2009, entered into between the company and Daniel Barnett (incorporated by reference from the registrant’s current Form 8-K, originally filed with the SEC on February 26, 2009).
10.15	Form of Subscription Agreement for common stock (incorporated by reference from the registrant’s current Form 8-K, originally filed with the SEC on April 27, 2009).
10.16	Form of Subscription Agreement for common stock (incorporated by reference from the registrant’s current Form 8-K, originally filed with the SEC on July 27, 2009).

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14.1	Code of Business Conduct and Ethics (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
16.1	Letter on change in certifying accountant (incorporated by reference from, the company’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
21.1	List of subsidiaries (incorporated by reference from the registrant’s Form 10-SB, as amended, originally filed with the SEC on November 2, 2006).
23.1	Consent of Sullivan & Worcester LLP (included in Exhibit 5.1).
23.2#	Consent of Caturano and Company, P.C.
24.1	Power of Attorney (included on signature page).

#   Filed herewith

18

EX-3.1

Exhibit 3.1

AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

OF

AMERICAN DG ENERGY INC.

(Originally incorporated on July 24, 2001 as Virtual Electric Inc.)

American DG Energy Inc., a corporation organized and existing under the laws of the State of Delaware (the “Corporation”), hereby certifies as follows:

1.           Pursuant to Section 242 and 245 of the General Corporation Law of the State of Delaware, this Amended and Restated Certificate of Incorporation restates, integrates and further amends the provisions of the Corporation’s Certificate of Incorporation, as amended to the date of this filing. The original Certificate of Incorporation was filed with the Secretary of State of Delaware on July 24, 2001. This Amended and Restated Certificate of Incorporation has been duly adopted and approved by the written consent of the directors and stockholders of the Corporation.

2.           The text of the Certificate of Incorporation, as amended to the date of this filing, is hereby restated and amended to read in its entirety as follows:

First:     The name of the Corporation is American DG Energy Inc.

Second: The address of the Corporation’s registered office in the State of Delaware is 1209 Orange Street, City of Wilmington, County of New Castle, Zip Code 19801, and the name of the registered agent of this Corporation in the State of Delaware at such address is The Corporation Trust Company.

Third:    The nature of the business or purposes to be conducted or promoted by the Corporation is to engage in any lawful act or activity for which corporations may be organized under the General Corporation Law of Delaware.

Fourth:  The total number of shares of all classes of stock that the Corporation shall have authority to issue is 110,000,000 shares, consisting of (i) 100,000,000 shares of Common Stock, $.001 par value per share (“Common Stock”), and (ii) 10,000,000 shares of Preferred Stock, $.001 par value per share (“Preferred Stock”), all of which Preferred Stock will be undesignated.

The following is a statement of the designations and the powers, privileges and rights, and the qualifications, limitations or restrictions thereof in respect of each class of capital stock of the Corporation.

A. COMMON STOCK.

1.      General.  The voting, dividend and liquidation rights of the holders of the Common Stock are subject to and qualified by the rights of the holders of the Preferred Stock of any series as may be designated by the Board of Directors upon any issuance of the Preferred Stock of any series.

2.      Voting.  The holders of the Common Stock shall have voting rights at all meetings of stockholders, each such holder being entitled to one vote for each share thereof held by such holder; provided, however, that, except as otherwise required by law, holders of Common Stock shall not be entitled to vote on any amendment to this Certificate of Incorporation (which, as used herein, shall mean the certificate of incorporation of the Corporation, as amended from time to time, including the terms of any certificate of designations of any series of Preferred Stock) that relates solely to the terms of one or more outstanding series of Preferred Stock if the holders of such affected series are entitled, either separately or together as a class with the holders of one or more other such series, to vote thereon pursuant to this Certificate of Incorporation. There shall be no cumulative voting.

The number of authorized shares of Common Stock may be increased or decreased (but not below the number of shares thereof then outstanding) by the affirmative vote of the holders of a majority of the stock of the Corporation entitled to vote, irrespective of the provisions of Section 242(b)(2) of the General Corporation Law of Delaware.

1

3.      Dividends.  Dividends may be declared and paid on the Common Stock from funds lawfully available therefor as and when determined by the Board of Directors and subject to any preferential dividend or other rights of any then outstanding Preferred Stock.

4.      Liquidation.  Upon the dissolution or liquidation of the Corporation, whether voluntary or involuntary, holders of Common Stock will be entitled to receive all assets of the Corporation available for distribution to its stockholders, subject to any preferential or other rights of any then outstanding Preferred Stock.

B. PREFERRED STOCK.

Preferred Stock may be issued from time to time in one or more series, each of such series to have such terms as stated or expressed herein and in the resolution or resolutions providing for the issue of such series adopted by the Board of Directors of the Corporation as hereinafter provided. Any shares of Preferred Stock that may be redeemed, purchased or acquired by the Corporation may be reissued except as otherwise provided by law.

Authority is hereby expressly granted to the Board of Directors from time to time to issue the Preferred Stock in one or more series, and in connection with the creation of any such series, by resolution or resolutions providing for the issuance of the shares thereof, to determine and fix the number of shares of such series and such voting powers, full or limited, or no voting powers, and such designations, preferences and relative participating, optional or other special rights, and qualifications, limitations or restrictions thereof, including dividend rights, conversion rights, redemption privileges and liquidation preferences, as shall be stated and expressed in such resolutions, all to the full extent now or hereafter permitted by the General Corporation Law of Delaware. Without limiting the generality of the foregoing, the resolutions providing for issuance of any series of Preferred Stock may provide that such series shall be superior or rank equally or be junior to the Preferred Stock of any other series to the extent permitted by law.

The number of authorized shares of Preferred Stock may be increased or decreased (but not below the number of shares then outstanding) by the affirmative vote of the holders of a majority of the stock of the Corporation entitled to vote, irrespective of the provisions of Section 242(b)(2) of the General Corporation Law of Delaware.

Fifth:  Except as otherwise provided herein, the Corporation reserves the right to amend, alter, change or repeal any provision contained in this Certificate of Incorporation, in the manner now or hereafter prescribed by statute and this Certificate of Incorporation, and all rights conferred upon stockholders herein are granted subject to this reservation.

Sixth:  In furtherance and not in limitation of the powers conferred upon it by the laws of the State of Delaware, and subject to the terms of any series of Preferred Stock, the Board of Directors shall have the power to adopt, amend, alter or repeal the Corporation’s By-laws. The affirmative vote of a majority of the directors present at any regular or special meeting of the Board of Directors at which a quorum is present shall be required to adopt, amend, alter or repeal the Corporation’s By-laws. The Corporation’s By-laws also may be adopted, amended, altered or repealed by the affirmative vote of the holders of at least 75% of the votes that all the stockholders would be entitled to cast in any annual election of directors or class of directors, in addition to any other vote required by this Certificate of Incorporation. Notwithstanding any other provisions of law, this Certificate of Incorporation or the By-Laws of the Corporation, and notwithstanding the fact that a lesser percentage may be specified by law, the affirmative vote of the holders of at least 75% of the votes that all the stockholders would be entitled to cast in any annual election of directors or class of directors shall be required to amend or repeal, or to adopt any provision inconsistent with, this Article Sixth.

Seventh:  Except to the extent that the General Corporation Law of Delaware prohibits the elimination or limitation of liability of directors for breaches of fiduciary duty, no director of the Corporation shall be personally liable to the Corporation or its stockholders for monetary damages for any breach of fiduciary duty as a director, notwithstanding any provision of law imposing such liability. No amendment to or repeal of this provision shall apply to or have any effect on the liability or alleged liability of any director of the Corporation for or with respect to any acts or omissions of such director occurring prior to such amendment or repeal.

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Eighth:  The Corporation shall provide indemnification as follows:

1.           Actions, Suits and Proceedings Other than by or in the Right of the Corporation.  The Corporation shall indemnify each person who was or is a party or threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the Corporation) by reason of the fact that he or she is or was, or has agreed to become, a director or officer of the Corporation, or is or was serving, or has agreed to serve, at the request of the Corporation, as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or other enterprise (including any employee benefit plan) (all such persons being referred to hereafter as an “Indemnitee”), or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by or on behalf of Indemnitee in connection with such action, suit or proceeding and any appeal therefrom, if Indemnitee acted in good faith and in a manner that Indemnitee reasonably believed to be in, or not opposed to, the best interests of the Corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful. The termination of any action, suit or proceeding by judgment, order, settlement, conviction or upon a plea of nolo contendere or its equivalent, shall not, of itself, create a presumption that Indemnitee did not act in good faith and in a manner that Indemnitee reasonably believed to be in, or not opposed to, the best interests of the Corporation, and, with respect to any criminal action or proceeding, had reasonable cause to believe that his or her conduct was unlawful.

2.           Actions or Suits by or in the Right of the Corporation.  The Corporation shall indemnify any Indemnitee who was or is a party to or threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the Corporation to procure a judgment in its favor by reason of the fact that Indemnitee is or was, or has agreed to become, a director or officer of the Corporation, or is or was serving, or has agreed to serve, at the request of the Corporation, as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or other enterprise (including any employee benefit plan), or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including attorneys’ fees) and, to the extent permitted by law, amounts paid in settlement actually and reasonably incurred by or on behalf of Indemnitee in connection with such action, suit or proceeding and any appeal therefrom, if Indemnitee acted in good faith and in a manner that Indemnitee reasonably believed to be in, or not opposed to, the best interests of the Corporation, except that no indemnification shall be made under this Section 2 in respect of any claim, issue or matter as to which Indemnitee shall have been adjudged to be liable to the Corporation, unless, and only to the extent, that the Court of Chancery of Delaware shall determine upon application that, despite the adjudication of such liability but in view of all the circumstances of the case, Indemnitee is fairly and reasonably entitled to indemnity for such expenses (including attorneys’ fees) that the Court of Chancery of Delaware shall deem proper.

3.           Indemnification for Expenses of Successful Party.  Notwithstanding any other provisions of this Article, to the extent that an Indemnitee has been successful, on the merits or otherwise, in defense of any action, suit or proceeding referred to in Sections 1 and 2 of this Article Eighth, or in defense of any claim, issue or matter therein, or on appeal from any such action, suit or proceeding, Indemnitee shall be indemnified against all expenses (including attorneys’ fees) actually and reasonably incurred by or on behalf of Indemnitee in connection therewith. Without limiting the foregoing, if any action, suit or proceeding is disposed of, on the merits or otherwise (including a disposition without prejudice), without (i) the disposition being adverse to Indemnitee, (ii) an adjudication that Indemnitee was liable to the Corporation, (iii) a plea of guilty or nolo contendere by Indemnitee, (iv) an adjudication that Indemnitee did not act in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the Corporation, and (v) with respect to any criminal proceeding, an adjudication that Indemnitee had reasonable cause to believe his conduct was unlawful, Indemnitee shall be considered for the purposes hereof to have been wholly successful with respect thereto.

4.           Notification and Defense of Claim.  As a condition precedent to an Indemnitee’s right to be indemnified, such Indemnitee must notify the Corporation in writing as soon as practicable of any action, suit, proceeding or investigation involving such Indemnitee for which indemnity will or could be sought. With respect to any action, suit, proceeding or investigation of which the Corporation is so notified, the Corporation will be entitled to participate therein at its own expense and/or to assume the defense thereof at its own expense, with legal counsel reasonably acceptable to Indemnitee. After notice from the Corporation to Indemnitee of its election so to assume such defense, the Corporation shall not be liable to Indemnitee for any legal or other expenses subsequently incurred by Indemnitee in connection with such action, suit, proceeding or investigation, other than as provided below in this Section 4. Indemnitee shall have the right to employ his or her own counsel in connection with such action, suit, proceeding or investigation, but the fees and expenses of such counsel incurred after notice from the Corporation of its assumption of the defense thereof shall be at the expense of Indemnitee unless (i) the employment of counsel by Indemnitee has been authorized by the Corporation, (ii) counsel to Indemnitee shall have reasonably concluded that there may be a conflict of interest or position on any significant issue between the Corporation and Indemnitee in the conduct of the defense of such action, suit, proceeding or investigation or (iii) the Corporation shall not in fact have employed counsel to assume the defense of such action, suit, proceeding or investigation, in each of which cases the fees and expenses of counsel for Indemnitee shall be at the expense of the Corporation, except as otherwise expressly provided by this Article. The Corporation shall not be entitled, without the consent of Indemnitee, to assume the defense of any claim brought by or in the right of the Corporation or as to which counsel for Indemnitee shall have reasonably made the conclusion provided for in clause (ii) above. The Corporation shall not be required to indemnify Indemnitee under this Article Eighth for any amounts paid in settlement of any action, suit, proceeding or investigation effected without its written consent. The Corporation shall not settle any action, suit, proceeding or investigation in any manner that would impose any penalty or limitation on Indemnitee without Indemnitee’s written consent. Neither the Corporation nor Indemnitee will unreasonably withhold or delay its consent to any proposed settlement.

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5.           Advance of Expenses.  Subject to the provisions of Section 6 of this Article Eighth, in the event of any action, suit, proceeding or investigation of which the Corporation receives notice under this Article, any expenses (including attorneys’ fees) incurred by or on behalf of Indemnitee in defending an action, suit, proceeding or investigation or any appeal therefrom shall be paid by the Corporation in advance of the final disposition of such matter; provided, however, that the payment of such expenses incurred by or on behalf of Indemnitee in advance of the final disposition of such matter shall be made only upon receipt of an undertaking by or on behalf of Indemnitee to repay all amounts so advanced in the event that it shall ultimately be determined that Indemnitee is not entitled to be indemnified by the Corporation as authorized in this Article; and further provided that no such advancement of expenses shall be made under this Article Eighth if it is determined (in the manner described in Section 6) that (i) Indemnitee did not act in good faith and in a manner he reasonably believed to be in, or not opposed to, the best interests of the Corporation, or (ii) with respect to any criminal action or proceeding, Indemnitee had reasonable cause to believe his conduct was unlawful. Such undertaking shall be accepted without reference to the financial ability of Indemnitee to make such repayment.

6.           Procedure for Indemnification.  In order to obtain indemnification or advancement of expenses pursuant to Section 1, 2, 3 or 5 of this Article Eighth, an Indemnitee shall submit to the Corporation a written request. Any such advancement of expenses shall be made promptly, and in any event within 60 days after receipt by the Corporation of the written request of Indemnitee, unless (i) the Corporation has assumed the defense pursuant to Section 4 of this Article Eighth (and none of the circumstances described in Section 4 of this Article Eighth that would nonetheless entitle the Indemnitee to indemnification for the fees and expenses of separate counsel have occurred) or (ii) the Corporation determines within such 60-day period that Indemnitee did not meet the applicable standard of conduct set forth in Section 1, 2 or 5 of this Article Eighth, as the case may be. Any such indemnification, unless ordered by a court, shall be made with respect to requests under Section 1 or 2 only as authorized in the specific case upon a determination by the Corporation that the indemnification of Indemnitee is proper because Indemnitee has met the applicable standard of conduct set forth in Section 1 or 2, as the case may be. Such determination shall be made in each instance (a) by a majority vote of the directors of the Corporation consisting of persons who are not at that time parties to the action, suit or proceeding in question (“disinterested directors”), whether or not a quorum, (b) by a committee of disinterested directors designated by majority vote of disinterested directors, whether or not a quorum, (c) if there are no disinterested directors, or if the disinterested directors so direct, by independent legal counsel (who may, to the extent permitted by law, be regular legal counsel to the Corporation) in a written opinion, or (d) by the stockholders of the Corporation.

7.           Remedies.  The right to indemnification or advancement of expenses as granted by this Article shall be enforceable by Indemnitee in any court of competent jurisdiction. Neither the failure of the Corporation to have made a determination prior to the commencement of such action that indemnification is proper in the circumstances because Indemnitee has met the applicable standard of conduct, nor an actual determination by the Corporation pursuant to Section 6 of this Article Eighth that Indemnitee has not met such applicable standard of conduct, shall be a defense to the action or create a presumption that Indemnitee has not met the applicable standard of conduct. Indemnitee’s expenses (including attorneys’ fees) reasonably incurred in connection with successfully establishing Indemnitee’s right to indemnification, in whole or in part, in any such proceeding shall also be indemnified by the Corporation.

8.           Limitations.  Notwithstanding anything to the contrary in this Article, except as set forth in Section 7 of the Article Eighth, the Corporation shall not indemnify an Indemnitee pursuant to this Article Eighth in connection with a proceeding (or part thereof) initiated by such Indemnitee unless the initiation thereof was approved by the Board of Directors of the Corporation. Notwithstanding anything to the contrary in this Article, the Corporation shall not indemnify an Indemnitee to the extent such Indemnitee is reimbursed from the proceeds of insurance, and in the event the Corporation makes any indemnification payments to an Indemnitee and such Indemnitee is subsequently reimbursed from the proceeds of insurance, such Indemnitee shall promptly refund indemnification payments to the Corporation to the extent of such insurance reimbursement.

9.           Subsequent Amendment.  No amendment, termination or repeal of this Article or of the relevant provisions of the General Corporation Law of Delaware or any other applicable laws shall affect or diminish in any way the rights of any Indemnitee to indemnification under the provisions hereof with respect to any action, suit, proceeding or investigation arising out of or relating to any actions, transactions or facts occurring prior to the final adoption of such amendment, termination or repeal.

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10.         Other Rights.  The indemnification and advancement of expenses provided by this Article shall not be deemed exclusive of any other rights to which an Indemnitee seeking indemnification or advancement of expenses may be entitled under any law (common or statutory), agreement or vote of stockholders or disinterested directors or otherwise, both as to action in Indemnitee’s official capacity and as to action in any other capacity while holding office for the Corporation, and shall continue as to an Indemnitee who has ceased to be a director or officer, and shall inure to the benefit of the estate, heirs, executors and administrators of Indemnitee. Nothing contained in this Article shall be deemed to prohibit, and the Corporation is specifically authorized to enter into, agreements with officers and directors providing indemnification rights and procedures different from those set forth in this Article. In addition, the Corporation may, to the extent authorized from time to time by its Board of Directors, grant indemnification rights to other employees or agents of the Corporation or other persons serving the Corporation and such rights may be equivalent to, or greater or less than, those set forth in this Article.

11.         Partial Indemnification.  If an Indemnitee is entitled under any provision of this Article to indemnification by the Corporation for some or a portion of the expenses (including attorneys’ fees), judgments, fines or amounts paid in settlement actually and reasonably incurred by or on behalf of Indemnitee in connection with any action, suit, proceeding or investigation and any appeal therefrom but not, however, for the total amount thereof, the Corporation shall nevertheless indemnify Indemnitee for the portion of such expenses (including attorneys’ fees), judgments, fines or amounts paid in settlement to which Indemnitee is entitled.

12.         Insurance.  The Corporation may purchase and maintain insurance, at its expense, to protect itself and any director, officer, employee or agent of the Corporation or another corporation, partnership, joint venture, trust or other enterprise (including any employee benefit plan) against any expense, liability or loss incurred by him in any such capacity, or arising out of his status as such, whether or not the Corporation would have the power to indemnify such person against such expense, liability or loss under the General Corporation Law of Delaware.

13.         Savings Clause.  If this Article or any portion hereof shall be invalidated on any ground by any court of competent jurisdiction, then the Corporation shall nevertheless indemnify each Indemnitee as to any expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement in connection with any action, suit, proceeding or investigation, whether civil, criminal or administrative, including an action by or in the right of the Corporation, to the fullest extent permitted by any applicable portion of this Article that shall not have been invalidated and to the fullest extent permitted by applicable law.

14.         Definitions.  Terms used herein and defined in Section 145(h) and Section 145(i) of the General Corporation Law of Delaware shall have the respective meanings assigned to such terms in such Section 145(h) and Section 145(i).

Ninth:   This Article is inserted for the management of the business and for the conduct of the affairs of the Corporation.

1.           General Powers.  The business and affairs of the Corporation shall be managed by or under the direction of the Board of Directors.

2.           Number of Directors; Election of Directors.  Subject to the rights of holders of any series of Preferred Stock to elect directors, the number of directors of the Corporation shall be established by the Board of Directors. Election of directors need not be by written ballot, except as and to the extent provided in the By-laws of the Corporation.

3.           Classes of Directors.  Subject to the rights of holders of any series of Preferred Stock to elect directors, the Board of Directors shall consist of one class.

4.           Terms of Office.  Subject to the rights of holders of any series of Preferred Stock to elect directors, each director shall serve for a term ending on the date of the next annual meeting following the annual meeting at which such director was elected; provided that the term of any person who is a director of the Corporation on the date of filing of this Amended and Restated Certificate of Incorporation with the Secretary of State of Delaware shall expire at the Corporation’s annual meeting of stockholders held in 2006; and provided further that the term of each director shall continue until the election and qualification of his successor and be subject to his earlier death, resignation or removal.

5.           Quorum.  The greater of (a) a majority of the directors at any time in office and (b) one-third of the number of directors fixed pursuant to Section 2 of this Article Ninth shall constitute a quorum. If at any meeting of the Board of Directors there shall be less than such a quorum, a majority of the directors present may adjourn the meeting from time to time without further notice other than announcement at the meeting, until a quorum shall be present.

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6.           Action at Meeting.  Every act, or decision done or made by a majority of the directors present at a meeting duly held at which a quorum is present shall be regarded as the act of the Board of Directors unless a greater number is required by law or by this Certificate of Incorporation.

7.           Removal.  Subject to the rights of holders of any series of Preferred Stock, directors of the Corporation may be removed only for cause and only by the affirmative vote of the holders of at least 75% of the votes that all the stockholders would be entitled to cast in any annual election of directors.

8.           Vacancies.  Subject to the rights of holders of any series of Preferred Stock, any vacancy or newly created directorships in the Board of Directors, however occurring, shall be filled only by vote of a majority of the directors then in office, although less than a quorum, or by a sole remaining director and shall not be filled by the stockholders. A director elected to fill a vacancy shall hold office until the next annual election of directors, subject to the election and qualification of a successor and to such director’s earlier death, resignation or removal.

9.           Stockholder Nominations and Introduction of Business, Etc.  Advance notice of stockholder nominations for election of directors and other business to be brought by stockholders before a meeting of stockholders shall be given in the manner provided by the By-laws of the Corporation.

10.           Amendments to Article.  Notwithstanding any other provisions of law, this Certificate of Incorporation or the By-laws of the Corporation, and notwithstanding the fact that a lesser percentage may be specified by law, the affirmative vote of the holders of at least 75% of the votes that all the stockholders would be entitled to cast in any annual election of directors shall be required to amend or repeal, or to adopt any provision inconsistent with, this Article Ninth.

Tenth:  Stockholders of the Corporation may not take any action by written consent in lieu of a meeting. Notwithstanding any other provisions of law, this Certificate of Incorporation or the By-laws of the Corporation, and notwithstanding the fact that a lesser percentage may be specified by law, the affirmative vote of the holders of at least 75% of the votes that all the stockholders would be entitled to cast in any annual election of directors or class of directors shall be required to amend or repeal, or to adopt any provision inconsistent with, this Article Tenth.

Eleventh:  Special meetings of stockholders for any purpose or purposes may be called at any time by the Board of Directors, the Chairman of the Board or the President, but such special meetings may not be called by any other person or persons. Business transacted at any special meeting of stockholders shall be limited to matters relating to the purpose or purposes stated in the notice of meeting. Notwithstanding any other provision of law, this Certificate of Incorporation or the By-laws of the Corporation, and notwithstanding the fact that a lesser percentage may be specified by law, the affirmative vote of the holders of at least 75% of the votes that all the stockholders would be entitled to cast in any annual election of directors or class of directors shall be required to amend or repeal, or to adopt any provision inconsistent with, this Article Eleventh.

IN WITNESS WHEREOF, this Certificate of Incorporation, which has been duly adopted in accordance with Sections 228, 242 and 245 of the Delaware General Corporation Law, has been executed by its duly authorized officer this December 9, 2009.

AMERICAN DG ENERGY INC.
By:	/s/ John N. Hatsopoulos
Name:	John N. Hatsopoulos
Title:	Chief Executive Officer

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EX-3.2

Exhibit 3.2

AMENDED AND RESTATED BY-LAWS

OF

AMERICAN DG ENERGY INC.

(as of August 31, 2009)

ARTICLE I.

STOCKHOLDERS

        1.1    Place of Meetings.    All meetings of stockholders shall be held at such place as may be designated from time to time by the Board of Directors, the Chairman of the Board, the Chief Executive Officer or the President or, if not so designated, at the principal office of the corporation.

        1.2    Annual Meeting.    The annual meeting of stockholders for the election of directors and for the transaction of such other business as may properly be brought before the meeting shall be held on a date and at a time designated by the Board of Directors, the Chairman of the Board, the Chief Executive Officer or the President (which date shall not be a legal holiday in the place where the meeting is to be held). If no annual meeting is held in accordance with the foregoing provisions, a special meeting may be held in lieu of the annual meeting, and any action taken at that special meeting shall have the same effect as if it had been taken at the annual meeting, and in such case all references in these By-laws to the annual meeting of the stockholders shall be deemed to refer to such special meeting.

        1.3    Special Meetings.    Special meetings of stockholders for any purpose or purposes may be called at any time by the Board of Directors, the Chairman of the Board, the Chief Executive Officer or the President, but such special meetings may not be called by any other person or persons. Business transacted at any special meeting of stockholders shall be limited to matters relating to the purpose or purposes stated in the notice of meeting.

        1.4    Notice of Meetings.    Except as otherwise provided by law, notice of each meeting of stockholders, whether annual or special, shall be given not less than 10 nor more than 60 days before the date of the meeting to each stockholder entitled to vote at such meeting. Without limiting the manner by which notice otherwise may be given to stockholders, any notice shall be effective if given by a form of electronic transmission consented to (in a manner consistent with the General Corporation Law of the State of Delaware) by the stockholder to whom the notice is given. The notices of all meetings shall state the place, date and time of the meeting and the means of remote communications, if any, by which stockholders and proxy holders may be deemed to be present in person and vote at such meeting. The notice of a special meeting shall state, in addition, the purpose or purposes for which the meeting is called. If notice is given by mail, such notice shall be deemed given when deposited in the United States mail, postage prepaid, directed to the stockholder at such stockholder's address as it appears on the records of the corporation. If notice is given by electronic transmission, such notice shall be deemed given at the time specified in Section 232 of the General Corporation Law of the State of Delaware.

        1.5    Voting List.    The Secretary shall prepare, at least 10 days before every meeting of stockholders, a complete list of the stockholders entitled to vote at the meeting, arranged in alphabetical order, and showing the address of each stockholder and the number of shares registered in the name of each stockholder. Such list shall be open to the examination of any stockholder, for any purpose germane to the meeting, for a period of at least 10 days prior to the meeting: (a) on a reasonably accessible electronic network, provided that the information required to gain access to such list is provided with notice of the meeting, or (b) during ordinary business hours, at the principal place of business of the corporation. The list shall also be produced and kept at the time and place of the meeting during the whole time thereof, and may be inspected by any stockholder who is present.

        1.6    Quorum.    Except as otherwise provided by law, the Certificate of Incorporation or these By-laws, the holders of a majority in voting power of the shares of the capital stock of the corporation issued and outstanding and entitled to vote at the meeting, present in person, present by means of remote communication in a manner, if any, authorized by the Board of Directors in its sole discretion, or represented by proxy, shall constitute a quorum for the transaction of business. A quorum, once established at a meeting, shall not be broken by the withdrawal of enough votes to leave less than a quorum.

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        1.7    Adjournments.    Any meeting of stockholders may be adjourned from time to time to any other time and to any other place at which a meeting of stockholders may be held under these By-laws by the stockholders present or represented at the meeting and entitled to vote, although less than a quorum, or, if no stockholder is present, by any officer entitled to preside at or to act as secretary of such meeting. It shall not be necessary to notify any stockholder of any adjournment of less than 30 days if the time and place of the adjourned meeting, and the means of remote communication, if any, by which stockholders and proxy holders may be deemed to be present in person and vote at such adjourned meeting, are announced at the meeting at which adjournment is taken, unless after the adjournment a new record date is fixed for the adjourned meeting. At the adjourned meeting, the corporation may transact any business that might have been transacted at the original meeting.

        1.8    Voting and Proxies.    Each stockholder shall have one vote for each share of stock entitled to vote held of record by such stockholder and a proportionate vote for each fractional share so held, unless otherwise provided by law or the Certificate of Incorporation. Each stockholder of record entitled to vote at a meeting of stockholders may vote in person (including by means of remote communications, if any, by which stockholders may be deemed to be present in person and vote at such meeting) or may authorize another person or persons to vote for such stockholder by a proxy executed or transmitted in a manner permitted by the General Corporation Law of the State of Delaware by the stockholder or such stockholder's authorized agent and delivered (including by electronic transmission) to the Secretary of the corporation. No such proxy shall be voted upon after three years from the date of its execution, unless the proxy expressly provides for a longer period.

        1.9    Action at Meeting.    When a quorum is present at any meeting, any matter other than the election of directors to be voted upon by the stockholders at such meeting shall be decided by the affirmative vote of the holders of a majority in voting power of the shares of stock present or represented and voting on such matter (or if there are two or more classes of stock entitled to vote as separate classes, then in the case of each such class, the holders of a majority in voting power of the shares of stock of that class present or represented and voting on such matter), except when a different vote is required by law, the Certificate of Incorporation or these By-laws. When a quorum is present at any meeting, any election by stockholders of directors shall be determined by a plurality of the votes cast by the stockholders entitled to vote on the election.

        1.10    Nomination of Directors.    

        (a)   Except for (1) any directors entitled to be elected by the holders of preferred stock, (2) any directors elected in accordance with Section 2.8 hereof by the Board of Directors to fill a vacancy or newly-created directorships or (3) as otherwise required by applicable law or stock market regulation, only persons who are nominated in accordance with the procedures in this Section 1.10 shall be eligible for election as directors. Nomination for election to the Board of Directors at a meeting of stockholders may be made (i) by or at the direction of the Board of Directors or (ii) by any stockholder of the corporation who (x) complies with the notice procedures set forth in Section 1.10(b) and (y) is a stockholder of record on the date of the giving of such notice and on the record date for the determination of stockholders entitled to vote at such meeting.

        (b)   To be timely, a stockholder's notice must be received in writing by the Secretary at the principal executive offices of the corporation as follows: (i) in the case of an election of directors at an annual meeting of stockholders, not less than 90 days nor more than 120 days prior to the first anniversary of the preceding year's annual meeting; provided, however, that in the event that the date of the annual meeting is advanced by more than 20 days, or delayed by more than 60 days, from the first anniversary of the preceding year's annual meeting, a stockholder's notice must be so received no earlier than the 120th day prior to such annual meeting and not later than the close of business on the later of (A) the 90th day prior to such annual meeting and (B) the tenth day following the day on which notice of the date of such annual meeting was mailed or public disclosure of the date of such annual meeting was made, whichever first occurs; or (ii) in the case of an election of directors at a special meeting of stockholders, provided that the Board of Directors has determined that directors shall be elected at such meeting, not earlier than the 120th day prior to such special meeting and not later than the close of business on the later of (x) the 90th day prior to such special meeting and (y) the tenth day following the day on which notice of the date of such special meeting was mailed or public disclosure of the date of such special meeting was made, whichever first occurs. In no event shall the adjournment or postponement of an annual meeting (or the public announcement thereof) commence a new time period (or extend any time period) for the giving of a stockholder's notice.

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The stockholder's notice to the Secretary shall set forth: (A) as to each proposed nominee (1) such person's name, age, business address and, if known, residence address, (2) such person's principal occupation or employment, (3) the class and number of shares of stock of the corporation that are beneficially owned by such person, and (4) any other information concerning such person that must be disclosed as to nominees in proxy solicitations pursuant to Regulation 14A under the Securities Exchange Act of 1934, as amended (the "Exchange Act"); (B) as to the stockholder giving the notice (1) such stockholder's name and address, as they appear on the corporation's books, (2) the class and number of shares of stock of the corporation that are owned, beneficially and of record, by such stockholder, (3) a description of all arrangements or understandings between such stockholder and each proposed nominee and any other person or persons (including their names) pursuant to which the nomination(s) are to be made by such stockholder, (4) a representation that such stockholder intends to appear in person or by proxy at the meeting to nominate the person(s) named in its notice and (5) a representation whether the stockholder intends or is part of a group that intends (x) to deliver a proxy statement and/or form of proxy to holders of at least the percentage of the corporation's outstanding capital stock required to elect the nominee and/or (y) otherwise to solicit proxies from stockholders in support of such nomination; and (C) as to the beneficial owner, if any, on whose behalf the nomination is being made (1) such beneficial owner's name and address, (2) the class and number of shares of stock of the corporation that are beneficially owned by such beneficial owner, (3) a description of all arrangements or understandings between such beneficial owner and each proposed nominee and any other person or persons (including their names) pursuant to which the nomination(s) are to be made and (4) a representation whether the beneficial owner intends or is part of a group that intends (x) to deliver a proxy statement and/or form of proxy to holders of at least the percentage of the corporation's outstanding capital stock requirement to elect the nominee and/or (y) otherwise to solicit proxies from stockholders in support of such nomination. In addition, to be effective, the stockholder's notice must be accompanied by the written consent of the proposed nominee to serve as a director if elected. The corporation may require any proposed nominee to furnish such other information as may reasonably be required to determine the eligibility of such proposed nominee to serve as a director of the corporation. A stockholder shall not have complied with this Section 1.10(b) if the stockholder (or beneficial owner, if any, on whose behalf the nomination is made) solicits or does not solicit, as the case may be, proxies in support of such stockholder's nominee in contravention of the representations with respect thereto required by this Section 1.10.

        (c)   The chairman of any meeting shall have the power and duty to determine whether a nomination was made in accordance with the provisions of this Section 1.10 (including whether the stockholder or beneficial owner, if any, on whose behalf the nomination is made solicited (or is part of a group that solicited) or did not so solicit, as the case may be, proxies in support of such stockholder's nominee in compliance with the representations with respect thereto required by this Section 1.10), and if the chairman should determine that a nomination was not made in accordance with the provisions of this Section 1.10, the chairman shall so declare to the meeting and such nomination shall be disregarded.

        (d)   Except as otherwise required by law, nothing in this Section 1.10 shall obligate the corporation or the Board of Directors to include in any proxy statement or other stockholder communication distributed on behalf of the corporation or the Board of Directors information with respect to any nominee for director submitted by a stockholder.

        (e)   Notwithstanding the foregoing provisions of this Section 1.10, if the stockholder (or a qualified representative of the stockholder) does not appear at the annual or special meeting of stockholders of the corporation to present a nomination, such nomination shall be disregarded, notwithstanding that proxies in respect of such vote may have been received by the corporation. For purposes of this Section 1.10, to be considered a qualified representative of the stockholder, a person must be authorized by a written instrument executed by such stockholder or an electronic transmission delivered by such stockholder to act for such stockholder as proxy at the meeting of stockholders and such person must produce such written instrument or electronic transmission, or a reliable reproduction of the written instrument or electronic transmission, at the meeting of stockholders.

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        (f)    For purposes of this Section 1.10, "public disclosure" shall include disclosure in a press release reported by the Dow Jones News Service, Associated Press or comparable national news service or in a document publicly filed by the corporation with the Securities and Exchange Commission pursuant to Section 13, 14 or 15(d) of the Exchange Act.

        1.11    Notice of Business at Annual Meetings.    

        (a)   At any annual meeting of the stockholders, only such business shall be conducted as shall have been properly brought before the meeting. To be properly brought before an annual meeting, business must be (1) specified in the notice of meeting (or any supplement thereto) given by or at the direction of the Board of Directors, (2) otherwise properly brought before the meeting by or at the direction of the Board of Directors, or (3) properly brought before the meeting by a stockholder. For business to be properly brought before an annual meeting by a stockholder, (i) if such business relates to the nomination of a person for election as a director of the corporation, the procedures in Section 1.10 must be complied with and (ii) if such business relates to any other matter, the business must constitute a proper matter under Delaware law for stockholder action and the stockholder must (x) have given timely notice thereof in writing to the Secretary in accordance with the procedures set forth in Section 1.11(b) and (y) be a stockholder of record on the date of the giving of such notice and on the record date for the determination of stockholders entitled to vote at such annual meeting.

        (b)   To be timely, a stockholder's notice must be received in writing by the Secretary at the principal executive offices of the corporation not less than 90 days nor more than 120 days prior to the first anniversary of the preceding year's annual meeting; provided, however, that in the event that the date of the annual meeting is advanced by more than 20 days, or delayed by more than 60 days, from the first anniversary of the preceding year's annual meeting, a stockholder's notice must be so received no earlier than the 120th day prior to such annual meeting and not later than the close of business on the later of (A) the 90th day prior to such annual meeting and (B) the tenth day following the day on which notice of the date of such annual meeting was mailed or public disclosure of the date of such annual meeting was made, whichever first occurs. In no event shall the adjournment or postponement of an annual meeting (or the public announcement thereof) commence a new time period (or extend any time period) for the giving of a stockholder's notice.

The stockholder's notice to the Secretary shall set forth as to each matter the stockholder proposes to bring before the annual meeting (1) a brief description of the business desired to be brought before the annual meeting, the text relating to the business (including the text of any resolutions proposed for consideration and in the event that such business includes a proposal to amend the By-laws, the language of the proposed amendment), and the reasons for conducting such business at the annual meeting, (2) the name and address, as they appear on the corporation's books, of the stockholder proposing such business, and the name and address of the beneficial owner, if any, on whose behalf the proposal is made, (3) the class and number of shares of stock of the corporation that are owned, of record and beneficially, by the stockholder and beneficial owner, if any, (4) a description of all arrangements or understandings between such stockholder or such beneficial owner, if any, and any other person or persons (including their names) in connection with the proposal of such business by such stockholder and any material interest of the stockholder or such beneficial owner, if any, in such business, (5) a representation that such stockholder intends to appear in person or by proxy at the annual meeting to bring such business before the meeting and (6) a representation whether the stockholder or the beneficial owner, if any, intends or is part of a group that intends (x) to deliver a proxy statement and/or form of proxy to holders of at least the percentage of the corporation's outstanding capital stock required to approve or adopt the proposal and/or (y) otherwise to solicit proxies from stockholders in support of such proposal. Notwithstanding anything in these By-laws to the contrary, no business shall be conducted at any annual meeting of stockholders except in accordance with the procedures set forth in this Section 1.11; provided that any stockholder proposal that complies with Rule 14a-8 of the proxy rules (or any successor provision) promulgated under the Securities Exchange Act of 1934, as amended, and is to be included in the corporation's proxy statement for an annual meeting of stockholders shall be deemed to comply with the requirements of this Section 1.11. A stockholder shall not have complied with this Section 1.11(b) if the stockholder (or beneficial owner, if any, on whose behalf the nomination is made) solicits or does not solicit, as the case may be, proxies in support of such stockholder's proposal in contravention of the representations with respect thereto required by this Section 1.11.

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        (c)   The chairman of any meeting shall have the power and duty to determine whether business was properly brought before the meeting in accordance with the provisions of this Section 1.11 (including whether the stockholder or beneficial owner, if any, on whose behalf the proposal is made solicited (or is part of a group that solicited) or did not so solicit, as the case may be, proxies in support of such stockholder's proposal in compliance with the representation with respect thereto required by this Section 1.11), and if the chairman should determine that business was not properly brought before the meeting in accordance with the provisions of this Section 1.11, the chairman shall so declare to the meeting and such business shall not be brought before the meeting.

        (d)   Notwithstanding the foregoing provisions of this Section 1.11, if the stockholder (or a qualified representative of the stockholder) does not appear at the annual meeting of stockholders of the corporation to present business, such business shall not be considered, notwithstanding that proxies in respect of such vote may have been received by the corporation. For purposes of this Section 1.11, to be considered a qualified representative of the stockholder, a person must be authorized by a written instrument executed by such stockholder or an electronic transmission delivered by such stockholder to act for such stockholder as a proxy at the meeting of stockholders and such person must produce such written instrument or electronic transmission, or a reliable reproduction of the written instrument or electronic transmission, at the meeting of stockholders.

        (e)   For purposes of this Section 1.11, "public disclosure" shall include disclosure in a press release reported by the Dow Jones New Service, Associated Press or comparable national news service or in a document publicly filed by the corporation with the Securities and Exchange Commission pursuant to Section 13, 14 or 15(d) of the Exchange Act.

        1.12    Conduct of Meetings.    

        (a)   Meetings of stockholders shall be presided over by the Chairman of the Board, if any, or in the Chairman's absence by the Vice Chairman of the Board, if any, or in the Vice Chairman's absence by the Chief Executive Officer, or in the Chief Executive Officer's absence, by the President, or in the President's absence by a Vice President, or in the absence of all of the foregoing persons by a chairman designated by the Board of Directors, or in the absence of such designation by a chairman chosen by vote of the stockholders at the meeting. The Secretary shall act as secretary of the meeting, but in the Secretary's absence the chairman of the meeting may appoint any person to act as secretary of the meeting.

        (b)   The Board of Directors may adopt by resolution such rules, regulations and procedures for the conduct of any meeting of stockholders of the corporation as it shall deem appropriate including such guidelines and procedures as it may deem appropriate regarding the participation by means of remote communication of stockholders and proxy holders not physically present at a meeting. Except to the extent inconsistent with such rules, regulations and procedures as adopted by the Board of Directors, the chairman of any meeting of stockholders shall have the right and authority to prescribe such rules, regulations and procedures and to do all such acts as, in the judgment of such chairman, are appropriate for the proper conduct of the meeting. Such rules, regulations or procedures, whether adopted by the Board of Directors or prescribed by the chairman of the meeting, may include, without limitation, the following: (i) the establishment of an agenda or order of business for the meeting; (ii) rules and procedures for maintaining order at the meeting and the safety of those present; (iii) limitations on attendance at or participation in the meeting to stockholders of record of the corporation, their duly authorized and constituted proxies or such other persons as shall be determined; (iv) restrictions on entry to the meeting after the time fixed for the commencement thereof; and (v) limitations on the time allotted to questions or comments by participants. Unless and to the extent determined by the Board of Directors or the chairman of the meeting, meetings of stockholders shall not be required to be held in accordance with the rules of parliamentary procedure.

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        (c)   The chairman of the meeting shall announce at the meeting when the polls for each matter to be voted upon at the meeting will be opened and closed. If no announcement is made, the polls shall be deemed to have opened when the meeting is convened and closed upon the final adjournment of the meeting. After the polls close, no ballots, proxies or votes or any revocations or changes thereto may be accepted.

        (d)   In advance of any meeting of stockholders, the Board of Directors, the Chairman of the Board, the Chief Executive Officer or the President shall appoint one or more inspectors of election to act at the meeting and make a written report thereof. One or more other persons may be designated as alternate inspectors to replace any inspector who fails to act. If no inspector or alternate is present, ready and willing to act at a meeting of stockholders, the chairman of the meeting shall appoint one or more inspectors to act at the meeting. Unless otherwise required by law, inspectors may be officers, employees or agents of the corporation. Each inspector, before entering upon the discharge of such inspector's duties, shall take and sign an oath faithfully to execute the duties of inspector with strict impartiality and according to the best of such inspector's ability. The inspector shall have the duties prescribed by law and shall take charge of the polls and, when the vote in completed, shall make a certificate of the result of the vote taken and of such other facts as may be required by law.

    1.13     Consent in Lieu of a Meeting.     Unless otherwise restricted by the Certificate of Incorporation, any action required or permitted by the Delaware General Corporation Law to be taken at any annual or special meeting of the stockholders of the Corporation, may be taken without a meeting, without prior notice and without a vote, if a consent or consents in writing or by electronic transmission, setting forth the action so taken, shall be signed or delivered by the holders of outstanding stock having not less than the minimum number of votes that would be necessary to take such action at a meeting at which all shares entitled to vote thereon were present and voted consent.

Prompt notice of the taking of the corporate action without a meeting by less than unanimous written consent shall be given to those stockholders who have not consented to the action taken.

ARTICLE II.

DIRECTORS

        2.1    General Powers.    The business and affairs of the corporation shall be managed by or under the direction of a Board of Directors, who may exercise all of the powers of the corporation except as otherwise provided by law or the Certificate of Incorporation.

        2.2    Number, Election and Qualification.    Subject to the rights of holders of any series of preferred stock to elect directors, the number of directors of the Corporation shall be established by the Board of Directors. Election of directors need not be by written ballot. Directors need not be stockholders of the corporation.

        2.3    Classes of Directors.    Subject to the rights of holders of any series of preferred stock to elect directors, the Board of Directors shall consist of one class.

        2.4    Terms of Office.    Subject to the rights of holders of any series of preferred stock to elect directors, each director shall serve for a term ending on the date of the first annual meeting following the annual meeting at which such director was elected; provided that the term of each director shall continue until the election and qualification of a successor and be subject to such director's earlier death, resignation or removal.

        2.5    Quorum.    The greater of (a) a majority of the directors at any time in office and (b) one-third of the number of directors fixed by the Board of Directors shall constitute a quorum. If at any meeting of the Board of Directors there shall be less than such a quorum, a majority of the directors present may adjourn the meeting from time to time without further notice other than announcement at the meeting, until a quorum shall be present.

        2.6    Action at Meeting.    Every act or decision done or made by a majority of the directors present at a meeting duly held at which a quorum is present shall be regarded as the act of the Board of Directors unless a greater number is required by law or by the Certificate of Incorporation.

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        2.7    Removal.    Subject to the rights of holder of any series of preferred stock, directors of the corporation may be removed only for cause and only by the affirmative vote of the holders of at least 75% of the votes that all the stockholders would be entitled to cast in any annual election of directors or class of directors.

        2.8    Vacancies.    Subject to the rights of holder of any series of preferred stock, any vacancy or newly-created directorships on the Board of Directors, however occurring, shall be filled only by vote of a majority of the directors then in office, although less than a quorum, or by a sole remaining director and shall not be filled by the stockholders. A director elected to fill a vacancy shall hold office until the next election of the class for which such director shall have been chosen, subject to the election and qualification of a successor or until such director's earlier death, resignation or removal.

        2.9    Resignation.    Any director may resign by delivering a resignation in writing or by electronic transmission to the corporation at its principal office or to the Chairman of the Board, the Chief Executive Officer, the President or the Secretary. Such resignation shall be effective upon receipt unless it is specified to be effective at some later time or upon the happening of some later event.

        2.10    Regular Meetings.    Regular meetings of the Board of Directors may be held without notice at such time and place as shall be determined from time to time by the Board of Directors; provided that any director who is absent when such a determination is made shall be given notice of the determination. A regular meeting of the Board of Directors may be held without notice immediately after and at the same place as the annual meeting of stockholders.

        2.11    Special Meetings.    Special meetings of the Board of Directors may be held at any time and place designated in a call by the Chairman of the Board, the Chief Executive Officer, the President, two or more directors, or by one director in the event that there is only a single director in office.

        2.12    Notice of Special Meetings.    Notice of any special meeting of directors shall be given to each director by the Secretary or by the officer or one of the directors calling the meeting. Notice shall be duly given to each director (a) in person or by telephone at least 24 hours in advance of the meeting, (b) by sending written notice via reputable overnight courier, telecopy or electronic mail, or delivering written notice by hand, to such director's last known business, home or electronic mail address at least 48 hours in advance of the meeting, or (c) by sending written notice via first-class mail to such director's last known business or home address at least 72 hours in advance of the meeting. A notice or waiver of notice of a meeting of the Board of Directors need not specify the purposes of the meeting.

        2.13    Meetings by Conference Communications Equipment.    Directors may participate in meetings of the Board of Directors or any committee thereof by means of conference telephone or other communications equipment by means of which all persons participating in the meeting can hear each other, and participation by such means shall constitute presence in person at such meeting.

        2.14    Action by Consent.    Any action required or permitted to be taken at any meeting of the Board of Directors or of any committee thereof may be taken without a meeting, if all members of the Board of Directors or committee, as the case may be, consent to the action in writing or by electronic transmission, and the written consents or electronic transmissions are filed with the minutes of proceedings of the Board of Directors or committee.

        2.15    Committees.    The Board of Directors may designate one or more committees, each committee to consist of one or more of the directors of the corporation. The Board of Directors may designate one or more directors as alternate members of any committee, who may replace any absent or disqualified member at any meeting of the committee. In the absence or disqualification of a member of a committee, the member or members of the committee present at any meeting and not disqualified from voting, whether or not such member or members constitute a quorum, may unanimously appoint another member of the Board of Directors to act at the meeting in the place of any such absent or disqualified member. Any such committee, to the extent provided in the resolution of the Board of Directors and subject to the provisions of law, shall have and may exercise all the powers and authority of the Board of Directors in the management of the business and affairs of the corporation and may authorize the seal of the corporation to be affixed to all papers that may require it. Each such committee shall keep minutes and make such reports as the Board of Directors may from time to time request. Except as the Board of Directors may otherwise determine, any committee may make rules for the conduct of its business, but unless otherwise provided by the directors or in such rules, its business shall be conducted as nearly as possible in the same manner as is provided in these By-laws for the Board of Directors. Except as otherwise provided in the Certificate of Incorporation, these By-laws, or the resolution of the Board of Directors designating the committee, a committee may create one or more subcommittees, each subcommittee to consist of one or more members of the committee, and delegate to a subcommittee any or all of the powers and authority of the committee.

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        2.16    Compensation of Directors.    Directors may be paid such compensation for their services and such reimbursement for expenses of attendance at meetings as the Board of Directors may from time to time determine. No such payment shall preclude any director from serving the corporation or any of its parent or subsidiary entities in any other capacity and receiving compensation for such service.

ARTICLE III.

OFFICERS

        3.1    Titles.    The officers of the corporation shall consist of a Chief Executive Officer, a President, a Secretary, a Treasurer and such other officers with such other titles as the Board of Directors shall determine, including a Chairman of the Board, a Vice Chairman of the Board, and one or more Vice Presidents, Assistant Treasurers, and Assistant Secretaries. The Board of Directors may appoint such other officers as it may deem appropriate.

        3.2    Election.    The Chief Executive Officer, President, Treasurer and Secretary shall be elected annually by the Board of Directors at its first meeting following the annual meeting of stockholders. Other officers may be appointed by the Board of Directors at such meeting or at any other meeting.

        3.3    Qualification.    No officer need be a stockholder. Any two or more offices may be held by the same person.

        3.4    Tenure.    Except as otherwise provided by law, by the Certificate of Incorporation or by these By-laws, each officer shall hold office until such officer's successor is elected and qualified, unless a different term is specified in the resolution electing or appointing such officer, or until such officer's earlier death, resignation or removal.

        3.5    Resignation and Removal.    Any officer may resign by delivering a written resignation to the corporation at its principal office or to the Chief Executive Officer, the President or the Secretary. Such resignation shall be effective upon receipt unless it is specified to be effective at some later time or upon the happening of some later event. Any officer may be removed at any time, with or without cause, by vote of a majority of the directors then in office. Except as the Board of Directors may otherwise determine, no officer who resigns or is removed shall have any right to any compensation as an officer for any period following such officer's resignation or removal, or any right to damages on account of such removal, whether such officer's compensation be by the month or by the year or otherwise, unless such compensation is expressly provided for in a duly authorized written agreement with the corporation.

        3.6    Vacancies.    The Board of Directors may fill any vacancy occurring in any office for any reason and may, in its discretion, leave unfilled for such period as it may determine any offices other than those of Chief Executive Officer, President, Treasurer and Secretary. Each such successor shall hold office for the unexpired term of such officer's predecessor and until a successor is elected and qualified, or until such officer's earlier death, resignation or removal.

        3.7    Chairman of the Board.    The Board of Directors may appoint from its members a Chairman of the Board, who need not be an employee or officer of the corporation. If the Board of Directors appoints a Chairman of the Board, such Chairman shall perform such duties and possess such powers as are assigned by the Board of Directors and, if the Chairman of the Board is also designated as the corporation's Chief Executive Officer, shall have the powers and duties of the Chief Executive Officer prescribed in Section 3.8 of these By-laws. Unless otherwise provided by the Board of Directors, the Chairman of the Board shall preside at all meetings of the Board of Directors and stockholders.

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        3.8    President; Chief Executive Officer.    Unless the Board of Directors has designated the Chairman of the Board or another person as the corporation's Chief Executive Officer, the President shall be the Chief Executive Officer of the corporation. The Chief Executive Officer shall have general charge and supervision of the business of the Corporation subject to the direction of the Board of Directors. The President shall perform such other duties and shall have such other powers as the Board of Directors or the Chief Executive Officer (if the President is not the Chief Executive Officer) may from time to time prescribe. In the event of the absence, inability or refusal to act of the Chief Executive Officer or the President (if the President is not the Chief Executive Officer), the Vice President (or if there shall be more than one, the Vice Presidents in the order determined by the Board of Directors) shall perform the duties of the Chief Executive Officer and when so performing such duties shall have all the powers of and be subject to all the restrictions upon the Chief Executive Officer.

        3.9    Vice Presidents.    Any Vice President shall perform such duties and possess such powers as the Board of Directors or the Chief Executive Officer may from time to time prescribe. The Board of Directors may assign to any Vice President the title of Executive Vice President, Senior Vice President or any other title selected by the Board of Directors.

        3.10    Secretary and Assistant Secretaries.    The Secretary shall perform such duties and shall have such powers as the Board of Directors or the Chief Executive Officer may from time to time prescribe. In addition, the Secretary shall perform such duties and have such powers as are incident to the office of the secretary, including the duty and power to give notices of all meetings of stockholders and special meetings of the Board of Directors, to attend all meetings of stockholders and the Board of Directors and keep a record of the proceedings, to maintain a stock ledger and prepare lists of stockholders and their addresses as required, to be custodian of corporate records and the corporate seal and to affix and attest to the same on documents. Any Assistant Secretary shall perform such duties and possess such powers as the Board of Directors, the Chief Executive Officer or the Secretary may from time to time prescribe. In the event of the absence, inability or refusal to act of the Secretary, the Assistant Secretary (or if there shall be more than one, the Assistant Secretaries in the order determined by the Board of Directors) shall perform the duties and exercise the powers of the Secretary. In the absence of the Secretary or any Assistant Secretary at any meeting of stockholders or directors, the chairman of the meeting shall designate a temporary secretary to keep a record of the meeting.

        3.11    Treasurer and Assistant Treasurers.    The Treasurer shall perform such duties and shall have such powers as may from time to time be assigned by the Board of Directors or the Chief Executive Officer. In addition, the Treasurer shall perform such duties and have such powers as are incident to the office of treasurer, including the duty and power to keep and be responsible for all funds and securities of the corporation, to deposit funds of the corporation in depositories selected in accordance with these By-laws, to disburse such funds as ordered by the Board of Directors, to make proper accounts of such funds, and to render as required by the Board of Directors statements of all such transactions and of the financial condition of the corporation. The Assistant Treasurers shall perform such duties and possess such powers as the Board of Directors, the Chief Executive Officer or the Treasurer may from time to time prescribe. In the event of the absence, inability or refusal to act of the Treasurer, the Assistant Treasurer (or if there shall be more than one, the Assistant Treasurers in the order determined by the Board of Directors) shall perform the duties and exercise the powers of the Treasurer.

        3.12    Salaries.    Officers of the corporation shall be entitled to such salaries, compensation or reimbursement as shall be fixed or allowed from time to time by the Board of Directors.

ARTICLE IV.

CAPITAL STOCK

          4.1. Issuance of Stock. Subject to the provisions of the Certificate of Incorporation, the whole or any part of any unissued balance of the authorized capital stock of the corporation or the whole or any part of any shares of the authorized capital stock of the corporation held in the corporation’s treasury may be issued, sold, transferred or otherwise disposed of by vote of the Board of Directors in such manner, for such lawful consideration and on such terms as the Board of Directors may determine.

               4.2. Stock Certificates; Uncertificated Shares. The shares of the corporation shall be represented by certificates, provided that the Board of Directors may provide by resolution or resolutions that some or all of any or all classes or series of its stock shall be uncertificated shares. Every holder of stock of the corporation represented by certificates shall be entitled to have a certificate, in such form as may be prescribed by law and by the Board of Directors, representing the number of shares held by such holder registered in certificate form. Each such certificate shall be signed in a manner that complies with Section 158 of the General Corporation Law of the State of Delaware.

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              Each certificate for shares of stock that are subject to any restriction on transfer pursuant to the Certificate of Incorporation, these By-laws, applicable securities laws or any agreement among any number of stockholders or among such holders and the corporation shall have conspicuously noted on the face or back of the certificate either the full text of the restriction or a statement of the existence of such restriction.  

              If the corporation shall be authorized to issue more than one class of stock or more than one series of any class, the powers, designations, preferences and relative participating, optional or other special rights of each class of stock or series thereof and the qualifications, limitations or restrictions of such preferences and/or rights shall be set forth in full or summarized on the face or back of each certificate representing shares of such class or series of stock, provided that in lieu of the foregoing requirements there may be set forth on the face or back of each certificate representing shares of such class or series of stock a statement that the corporation will furnish without charge to each stockholder who so requests a copy of the full text of the powers, designations, preferences and relative, participating, optional or other special rights of each class of stock or series thereof and the qualifications, limitations or restrictions of such preferences and/or rights.

              Within a reasonable time after the issuance or transfer of uncertificated stock, the corporation shall send to the registered owner thereof a written notice containing the information required to be set forth or stated on certificates pursuant to Sections 151, 202(a) or 218(a) of the General Corporation Law of the State of Delaware or, with respect to Section 151 of General Corporation Law of the State of Delaware, a statement that the corporation will furnish without charge to each stockholder who so requests the powers, designations, preferences and relative participating, optional or other special rights of each class of stock or series thereof and the qualifications, limitations or restrictions of such preferences and/or rights.

              4.3. Transfers. Shares of stock of the corporation shall be transferable in the manner prescribed by law and in these By-laws. Transfers of shares of stock of the corporation shall be made only on the books of the corporation or by transfer agents designated to transfer shares of stock of the corporation. Subject to applicable law, shares of stock represented by certificates shall be transferred only on the books of the corporation by the surrender to the corporation or its transfer agent of the certificate representing such shares properly endorsed or accompanied by a written assignment or power of attorney properly executed, and with such proof of authority or the authenticity of signature as the corporation or its transfer agent may reasonably require. Except as may be otherwise required by law, by the Certificate of Incorporation or by these By-laws, the corporation shall be entitled to treat the record holder of stock as shown on its books as the owner of such stock for all purposes, including the payment of dividends and the right to vote with respect to such stock, regardless of any transfer, pledge or other disposition of such stock until the shares have been transferred on the books of the corporation in accordance with the requirements of these By-laws.

              4.4. Lost, Stolen or Destroyed Certificates. The corporation may issue a new certificate of stock in place of any previously issued certificate alleged to have been lost, stolen or destroyed, upon such terms and conditions as the Board of Directors may prescribe, including the presentation of reasonable evidence of such loss, theft or destruction and the giving of such indemnity and posting of such bond as the Board of Directors may require for the protection of the corporation or any transfer agent or registrar.

              4.5. Record Date. The Board of Directors may fix in advance a date as a record date for the determination of the stockholders entitled to notice of or to vote at any meeting of stockholders, or entitled to receive payment of any dividend or other distribution or allotment of any rights in respect of any change, conversion or exchange of stock, or for the purpose of any other lawful action. Such record date shall not precede the date on which the resolution fixing the record date is adopted, and such record date shall not be more than 60 nor less than 10 days before the date of such meeting, nor more than 60 days prior to any other action to which such record date relates.

              If no record date is fixed, the record date for determining stockholders entitled to notice of or to vote at a meeting of stockholders shall be at the close of business on the day before the day on which notice is given, or, if notice is waived, at the close of business on the day before the day on which the meeting is held. If no record date is fixed, the record date for determining stockholders for any other purpose shall be at the close of business on the day on which the Board of Directors adopts the resolution relating to such purpose.

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A determination of stockholders of record entitled to notice of or to vote at a meeting of stockholders shall apply to any adjournment of the meeting; provided, however, that the Board of Directors may fix a new record date for the adjourned meeting.

              4.6. Regulations. The issue, transfer, conversion and registration of shares of stock of the corporation shall be governed by such other regulations as the Board of Directors may establish.

ARTICLE V.

GENERAL PROVISIONS

        5.1    Fiscal Year.    Except as from time to time otherwise designated by the Board of Directors, the fiscal year of the corporation shall begin on the first day of January of each year and end on the last day of December in each year.

        5.2    Corporate Seal.    The corporate seal shall be in such form as shall be approved by the Board of Directors.

        5.3    Waiver of Notice.    Whenever notice is required to be given by law, by the Certificate of Incorporation or by these By-laws, a written waiver signed by the person entitled to notice, or a waiver by electronic transmission by the person entitled to notice, whether before, at or after the time stated in such notice, shall be deemed equivalent to notice. Attendance of a person at a meeting shall constitute a waiver of notice of such meeting, except when the person attends a meeting for the express purpose of objecting at the beginning of the meeting, to the transaction of any business because the meeting is not lawfully called or convened.

        5.4    Voting of Securities.    Except as the Board of Directors may otherwise designate, the Chief Executive Officer, the President or the Treasurer may waive notice of, and act as, or appoint any person or persons to act as, proxy or attorney-in-fact for this corporation (with or without power of substitution) at any meeting of stockholders or security holders of any other entity, the securities of which may be held by this corporation.

        5.5    Evidence of Authority.    A certificate by the Secretary, or an Assistant Secretary, or a temporary Secretary, as to any action taken by the stockholders, directors, a committee or any officer or representative of the corporation shall as to all persons who rely on the certificate in good faith be conclusive evidence of such action.

        5.6    Certificate of Incorporation.    All references in these By-laws to the Certificate of Incorporation shall be deemed to refer to the Certificate of Incorporation of the corporation, as amended and in effect from time to time.

        5.7    Severability.    Any determination that any provision of these By-laws is for any reason inapplicable, illegal or ineffective shall not affect or invalidate any other provision of these By-laws.

        5.8    Pronouns.    All pronouns used in these By-laws shall be deemed to refer to the masculine, feminine or neuter, singular or plural, as the identity of the person or persons may require.

ARTICLE VI.

AMENDMENTS

        These By-laws may be altered, amended or repealed, in whole or in part, or new By-laws may be adopted by the Board of Directors or by the stockholders as provided in the Certificate of Incorporation.

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EX-5.1

Exhibit 5.1

Sullivan & Worcester LLP

One Post Office Square

Boston, MA 02109

December 23, 2009

American DG Energy Inc.

45 First Avenue

Waltham, MA 02451

Re: Registration Statement on Form S-1

File No. 333-159580

Ladies and Gentlemen:

The following opinion is being furnished to you in connection with the registration under the Securities Act of 1933, as amended (the “Securities Act”), by American DG Energy Inc., a Delaware corporation (the “Company”), of its Common Stock (the “Registered Shares”) consisting of the following: (i) 3,548,405 shares of Common Stock currently outstanding, (ii) 5,321,431 shares of Common Stock issuable upon conversion of outstanding convertible debt and (iii) 62,000 shares of Common Stock issuable upon the exercise of outstanding warrants. The Registered Shares are being registered for resale pursuant to the above-described registration statement (the “Registration Statement”) filed with the Securities and Exchange Commission (the “Commission”) pursuant to the Securities Act of 1933.

We have acted as counsel to the Company in connection with the Registration Statement, and we have examined originals or copies, certified or otherwise identified to our satisfaction, of the Registration Statement and such other documents as we have considered necessary in order to furnish the opinion hereinafter set forth.

We express no opinion herein as to any laws other than the Delaware General Corporation Law, the applicable provisions of the Delaware constitution and reported judicial decisions interpreting these laws, and the federal law of the United States, and we express no opinion as to state securities or blue sky laws.

Based on and subject to the foregoing, we are of the opinion that the outstanding shares of Common Stock being registered are, and the shares of Common Stock issuable upon conversion or exercise of convertible debt or warrants will be upon the valid conversion or exercise thereof will be, duly authorized, validly issued, fully paid and nonassessable.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement.  In giving such consent, we do not thereby admit that we come within the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission promulgated thereunder.

 Very truly yours,

SULLIVAN AND WORCESTER LLP

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EX-10.1

Exhibit 10.1

AMERICAN DG ENERGY INC.

Audit Committee Charter

(as amended October 13, 2009)

Purpose

The purpose of the Audit Committee is to assist the Board of Directors in overseeing the Company’s accounting and financial reporting processes and the audits of the Company’s financial statements.

Structure and Membership

Number.  Except as otherwise permitted by the applicable Nasdaq rules, the Audit Committee shall consist of at least three members of the Board of Directors.

Independence.  Except as otherwise permitted by the applicable Nasdaq rules, each member of the Audit Committee shall be independent as defined by Nasdaq rules, meet the criteria for independence set forth in Rule 10A-3(b)(l) under the Securities Exchange Act (subject to the exemptions provided in Rule 10A-3(c) under such Act), and not have participated in the preparation of the financial statements of the Company or any current subsidiary of the Company at any time during the past three years.

Financial Literacy.  Each member of the Audit Committee must be able to read and understand fundamental financial statements, including the Company’s balance sheet, income statement, and cash flow statement, at the time of his or her appointment to the Audit Committee. In addition, at least one member must have past employment experience in finance or accounting, requisite professional certification in accounting, or any other comparable experience or background which results in the individual’s financial sophistication, including being or having been a chief executive officer, chief financial officer or other senior officer with financial oversight responsibilities. Unless otherwise determined by the Board of Directors (in which case disclosure of such determination shall be made in the Company’s annual report filed with the Securities and Exchange Commission), at least one member of the Audit Committee shall be an “audit committee financial expert” (as defined by applicable Securities and Exchange Commission rules).

Chair.  Unless the Board of Directors elects a Chair of the Audit Committee, the Audit Committee shall elect a Chair by majority vote.

Compensation.  The compensation of Audit Committee members shall be as determined by the Board of Directors. No member of the Audit Committee may receive, directly or indirectly, any consulting, advisory or other compensatory fee from the Company or any of its subsidiaries, other than fees paid in his or her capacity as a member of the Board of Directors or a committee of the Board.

Selection and Removal.  Members of the Audit Committee shall be appointed by the Board of Directors. The Board of Directors may remove members of the Audit Committee from such committee, with or without cause.

Authority and Responsibilities

General

The Audit Committee shall discharge its responsibilities, and shall assess the information provided by the Company’s management and the independent auditor, in accordance with its business judgment. Management is responsible for the preparation, presentation, and integrity of the Company’s financial statements and for the appropriateness of the accounting principles and reporting policies that are used by the Company. The independent auditors are responsible for auditing the Company’s financial statements and for reviewing the Company’s unaudited interim financial statements. The authority and responsibilities set forth in this Charter do not reflect or create any duty or obligation of the Audit Committee to plan or conduct any audit, to determine or certify that the Company’s financial statements are complete, accurate, fairly presented, or in accordance with generally accepted accounting principles or applicable law, or to guarantee the independent auditor’s report.

Oversight of Independent Auditors

Selection.  The Audit Committee shall be solely and directly responsible for appointing, evaluating, retaining and, when necessary, terminating the engagement of the independent auditor. The Audit Committee may, in its discretion, seek stockholder ratification of the independent auditor it appoints.

Independence.  The Audit Committee shall take, or recommend that the full Board of Directors take, appropriate action to oversee the independence of the independent auditor. In connection with this responsibility, the Audit Committee shall obtain and review a formal written statement from the independent auditor describing all relationships between the auditor and the Company, including the disclosures required by Independence Standards Board Standard No. 1. The Audit Committee shall actively engage in dialogue with the auditor concerning any disclosed relationships or services that might impact the objectivity and independence of the auditor.

Compensation.  The Audit Committee shall have sole and direct responsibility for setting the compensation of the independent auditor. The Audit Committee is empowered, without further action by the Board of Directors, to cause the Company to pay the compensation of the independent auditor established by the Audit Committee.

Preapproval of Services.  The Audit Committee shall preapprove all audit services to be provided to the Company, whether provided by the principal auditor or other firms, and all other services (review, attest and non-audit) to be provided to the Company by the independent auditor; provided, however, that de minimis non-audit services may instead be approved in accordance with applicable Securities and Exchange Commission rules.

Oversight.  The independent auditor shall report directly to the Audit Committee, and the Audit Committee shall have sole and direct responsibility for overseeing the work of the independent auditor, including resolution of disagreements between Company management and the independent auditor regarding financial reporting. In connection with its oversight role, the Audit Committee shall, from time to time as appropriate, receive and consider the reports required to be made by the independent auditor regarding:

· critical accounting policies and practices;

· alternative treatments within generally accepted accounting principles for policies and practices related to material items that have been discussed with Company management, including ramifications of the use of such alternative disclosures and treatments, and the treatment preferred by the independent auditor; and

· other material written communications between the independent auditor and Company management.

Audited Financial Statements

Review and Discussion.  The Audit Committee shall review and discuss with the Company’s management and independent auditor the Company’s audited financial statements, including the matters about which Statement on Auditing Standards No. 61 (Codification of Statements on Auditing Standards, AU §380) requires discussion.

Recommendation to Board Regarding Financial Statements.  The Audit Committee shall consider whether it will recommend to the Board of Directors that the Company’s audited financial statements be included in the Company’s Annual Report on Form 10-K.

Audit Committee Report.  The Audit Committee shall prepare an annual committee report for inclusion where necessary in the proxy statement of the Company relating to its annual meeting of security holders.

Review of Other Financial Disclosures

Independent Auditor Review of Interim Financial Statements.  The Audit Committee shall direct the independent auditor to use its best efforts to perform all reviews of interim financial information prior to disclosure by the Company of such information and to discuss promptly with the Audit Committee and the Chief Financial Officer any matters identified in connection with the auditor’s review of interim financial information which are required to be discussed by applicable auditing standards. The Audit Committee shall direct management to advise the Audit Committee in the event that the Company proposes to disclose interim financial information prior to completion of the independent auditor’s review of interim financial information.

Controls and Procedures

Oversight.  The Audit Committee shall coordinate the Board of Directors’ oversight of the Company’s internal control over financial reporting, disclosure controls and procedures and code of conduct. The Audit Committee shall receive and review the reports of the CEO and CFO required by Rule 13a-14 of the Securities Exchange Act.

Procedures for Complaints.  The Audit Committee shall establish procedures for (a) the receipt, retention and treatment of complaints received by the Company regarding accounting, internal accounting controls or auditing matters and (b) the confidential, anonymous submission by employees of the Company of concerns regarding questionable accounting or auditing matters.

Related-Party Transactions.  The Audit Committee shall review all “related party transactions” (defined as transactions required to be disclosed pursuant to Item 404 of Regulation S-K promulgated by the Securities and Exchange Commission) on an ongoing basis, and all such transactions must be approved by the Audit Committee.

Additional Powers.  The Audit Committee shall have such other duties as may be delegated from time to time by the Board of Directors.

Procedures and Administration

Meetings.  The Audit Committee shall meet as often as it deems necessary in order to perform its responsibilities, but at least once each calendar quarter. The Audit Committee may also act by unanimous written consent in lieu of a meeting. The Audit Committee shall periodically meet separately with (a) the independent auditor and (b) Company management. The Audit Committee shall keep such records of its meetings as it shall deem appropriate.

Subcommittees.  The Audit Committee may form and delegate authority to one or more subcommittees (including a subcommittee consisting of a single member), as it deems appropriate from time to time under the circumstances. Any decision of a subcommittee to preapprove audit, review, attest or non-audit services shall be presented to the full Audit Committee at its next scheduled meeting.

Reports to Board.  The Audit Committee shall report regularly to the Board of Directors.

Charter.  At least annually, the Audit Committee shall review and reassess the adequacy of this Charter and recommend any proposed changes to the Board of Directors for approval.

Independent Advisors.  The Audit Committee is authorized, without further action by the Board of Directors, to engage such independent legal, accounting and other advisors as it deems necessary or appropriate to carry out its responsibilities. Such independent advisors may be the regular advisors to the Company. The Audit Committee is empowered, without further action by the Board of Directors, to cause the Company to pay the compensation of such advisors as established by the Audit Committee.

Investigations.  The Audit Committee shall have the authority to conduct or authorize investigations into any matters within the scope of its responsibilities as it shall deem appropriate, including the authority to request any officer, employee or advisor of the Company to meet with the Audit Committee or any advisors engaged by the Audit Committee.

Funding.  The Audit Committee is empowered, without further action by the Board of Directors, to cause the Company to pay the ordinary administrative expenses of the Audit Committee that are necessary or appropriate in carrying out its duties.

EX-10.3

Exhibit 10.3

AMERICAN DG ENERGY INC.

Nominating and Governance Committee Charter

The Nominating and Governance Committee (the “Committee”) of the Board of Directors (the “Board”) of American DG Energy Inc. (the “Company”) shall consist of a minimum of three (3) directors.  In the event one or more vacancies on the Committee temporarily reduce the number of members to two (2), actions taken by the two members of the Committee will be deemed authorized actions of the Committee.  Members of the Committee shall be appointed by the Board and shall serve until the meeting of the Board occurring immediately after the next following annual meeting of the stockholders, and until their successor are duly elected and qualified, unless they are earlier removed by the Board acting in its discretion.

Purpose

The purpose of the Committee shall be:

(1) to assist the Board by recommending the composition of the Board and in identifying individuals qualified to become Board members, consistent with criteria approved by the Board;

(2)         to advise the Board with respect to functions and structures of committees;

(3) to develop, recommend to the Board and implement corporate governance principles applicable to the Company;

(4) to assist the Board in providing for planned succession of senior management positions;

(5) to develop and monitor a process to assess the effectiveness of the Board and to lead the Board in its annual review of the Board’s performance; and

(6) to develop and propose for consideration by the Board compensation policies for the Company’s non-employee directors that enable the Company to retain highly qualified individuals for such positions.

In furtherance of this purpose, the Committee shall have the following authority and responsibilities:

1. To lead the search for individuals qualified to become members of the Board, consistent with criteria approved by the Board and to recommend to the Board nominees to be presented for election as directors by shareholders at each annual meeting of shareholders.  The Committee shall select individuals as director nominees who have the highest personal and professional integrity, who shall have demonstrated exceptional ability and judgment and who shall be most effective, in conjunction with the other nominees to and members of the Board, in collectively serving the long-term interests of the shareholders.

2. To review the Board’s committee structure and to recommend to the Board for its approval directors to serve as members of each committee.  The Committee shall review and recommend committee slates annually and shall recommend additional committee members to fill vacancies as needed.

3. To develop and recommend to the Board for its approval corporate governance guidelines.  The Committee shall review the guidelines on an annual basis, or more frequently if appropriate, and recommend changes as necessary.

4. To oversee the development and implementation of senior executive succession plans.

5. To develop and recommend to the Board for its approval an annual self-evaluation of the Board and its committees.  The Committee shall oversee the annual self-evaluation.  In addition, the Committee shall consider and evaluate other methods of assessing the effectiveness of the Board.

6. To review annually the Company’s compensation package for non-employee directors to ensure that compensation to such persons is competitive and appropriate, and to recommend changes, when appropriate, to the Board for approval.

Subcommittees

The Committee shall have the authority to delegate any of its responsibilities to subcommittees as the Committee may deem appropriate in its sole discretion.

Committee Membership Qualifications

All of the members of the Committee shall meet the independence requirements of the corporate governance rules of such national securities exchange on which the shares of Common Stock of the Company are listed.

Miscellaneous

The Committee shall have the authority to retain (or terminate) any search firm engaged to assist in identifying director candidates, and to retain outside counsel and any other advisors as the Committee may deem appropriate in its sole discretion.  The Committee shall have sole authority to approve related fees and retention terms.

The Committee shall report its actions and recommendations to the Board after each Committee meeting and shall conduct and present to the Board an annual performance evaluation of the Committee.  The Committee shall review at least annually the adequacy of this charter and recommend any proposed changes to the Board for approval.

Adopted:       August 31, 2009

EX-10.13

Exhibit 10.13

AMERICAN DG ENERGY INC.

COMMON STOCK PURCHASE AGREEMENT

TO: American DG Energy Inc.

45 First Avenue

Waltham, Massachusetts 02451

Ladies and Gentlemen:

The undersigned (the “Investor”) desires to purchase from American DG Energy Inc., a Delaware corporation (the “Company”), _______ shares of its Common Stock, par value $.001 per share (the “Common Stock”). The purchase price for each share of Common Stock is $0.70.

1.           Subscription

a.           Subject to the terms and conditions of this Agreement (this “Agreement”), the Investor agrees to subscribe for and purchase from the Company and tenders this subscription for _______ shares of Common Stock (the “Shares”) together with payment of the subscription price for the Shares in the amount of $________. The subscription price is referred to in this Agreement as the “Funds”.

b.           Tender of the Funds shall be made by delivery of a personal or bank check payable to the Company or by wire transfer to the Company’s designated bank account, together with executed copies of this Agreement. The Investor should deliver the executed subscription documents and payment for the Shares to the Company, at 45 First Avenue, Waltham, MA  02451 Attention: Anthony S. Loumidis, Chief Financial Officer, Phone (781) 622-1117.

2.           Acceptance of Agreement

It is understood and agreed that this Subscription is made subject to the following terms and conditions:

The Company shall have the right to accept or reject this Subscription, in whole or in part, for any reason, the ineligibility of a subscriber under applicable state or foreign securities laws, for any other reason or for no reason. If this Subscription is rejected, the Funds previously delivered to the Company will be returned to the Investor.

b.           Two complete copies of this Agreement will be executed by the Investor. If this Subscription is accepted, one copy of this Common Stock Purchase Agreement as accepted by the Company shall be delivered to the Investor.

c.           If this Subscription is accepted in part and rejected in part, the Investor will be so notified, at which time the excess Funds previously delivered to the Company will be returned to the Investor.

3.           Representations and Warranties of the Investor

In order to induce the Company to accept this Agreement, the Investor hereby represents and warrants to the Company as follows:

a.           THE INVESTOR HAS READ CAREFULLY AND UNDERSTANDS THIS AGREEMENT AND HAS CONSULTED THE INVESTOR'S OWN ATTORNEY, ACCOUNTANT OR INVESTMENT ADVISER WITH RESPECT TO THE INVESTMENT CONTEMPLATED HEREBY AND ITS SUITABILITY FOR THE INVESTOR.  THE INVESTOR HAS HAD AN OPPORTUNITY TO ASK QUESTIONS OF AND RECEIVED ANSWERS FROM THE COMPANY, OR A PERSON OR PERSONS ACTING ON THE COMPANY'S BEHALF, CONCERNING THE TERMS AND CONDITIONS OF THIS INVESTMENT AND THE BUSINESS OF THE COMPANY, AND HAS RECEIVED AND REVIEWED ALL ADDITIONAL DOCUMENTATION REGARDING THE BUSINESS AND OPERATIONS OF THE COMPANY THAT HE OR SHE HAS REASONABLY REQUESTED.

b.           The Investor (i) has no need for liquidity in the investment in the Shares, (ii) is able to bear the substantial economic risks of an investment in the Shares for an indefinite period, and (iii) at the present time, could afford the complete loss of such investment in the Shares.

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c.           The address set forth at the end of this Agreement is the Investor's true and correct residence, and the Investor has no present intention of changing such residence to any other state or jurisdiction.

d.           The Investor confirms that all documents, records and books pertaining to the investment in the Company reasonably requested by the Investor have been made available to the Investor. The undersigned has relied only on such documents and that no written or oral representation or information inconsistent with such information has been made or furnished to the Investor in connection with the Shares and if so made, has not been relied upon.

e.           The Investor understands that the Shares have not been registered under the Securities Act, nor pursuant to the provisions of the securities laws or other laws of any other applicable jurisdictions, in reliance on exemptions for private offerings contained in the Securities Act and in the laws of such jurisdictions. The Investor represents to the Company that he is an “accredited investor”, as such term is defined in Rule 501(a) of Regulation D under the Securities Act of 1933, as amended. The Investor is fully aware that the Shares to which he or she is subscribing are to be sold in reliance upon such exemptions based upon his or her representations, warranties and agreements set forth in this Agreement. The Investor is fully aware that he or she must bear the economic risk of his or her investment in the Company for an indefinite period of time because the Shares have not been registered under the Securities Act, and, therefore, cannot be offered or sold unless they are subsequently registered under the Securities Act or an exemption from such registration is available. The Investor further understands that the Company has no intention and is under no obligation to register its Shares under the Securities Act or to comply with the requirements for any exemption that might otherwise be available, or to supply the Investor with any information necessary to enable the Investor to make routine sales of the Shares under Rule 144under the Securities Act (which it understands is not now, and will not likely be, available) or any rule of the Securities and Exchange Commission or any successor thereto.

f.           The Investor understands that the certificate(s) representing the Shares will bear the following legend restricting its transfer and that a notation restricting such transfer will be made on the stock transfer books of the Company:

“THE SHARES OF STOCK REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT") OR THE APPLICABLE SECURITIES LAWS OF ANY STATE OR OTHER JURISDICTION. THESE SHARES HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO THEIR DISTRIBUTION OR RESALE.  SUCH SHARES MAY NOT BE SOLD, PLEDGED OR OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT FOR SUCH SHARES UNDER THE ACT, OR AN OPINION OF COUNSEL SATISFACTORY IN FORM AND SUBSTANCE TO THE COMPANY TO THE EFFECT THAT SUCH REGISTRATION IS NOT REQUIRED.”

g.           The Shares are being acquired solely for the Investor's own account, for investment and are not being purchased with a view to or for the resale or other distribution of the Shares; and the Investor has no present plans to enter into any contract, undertaking, agreement or arrangement relating to any resale or other distribution of the Shares.

h.           The Investor understands that this Subscription may be accepted or rejected in whole or in part in the sole and absolute discretion of the Company, and this Agreement, unless properly revoked before the completion of the sale of the Shares to the Investor, shall survive the Investor’s death, disability or insolvency, except that the Investor shall have no obligations in the event that this Subscription is rejected by the Company.

i.           The Investor understands that even if the Company becomes a "reporting company" under the Securities Exchange Act of 1934, as amended, the provisions of Rule 144 promulgated under the Securities Act permitting resales of the Shares will not be available for at least one (1) year, and there can be no assurance that the conditions necessary to permit routine sales of the Shares under Rule 144 will ever be satisfied, and, if Rule 144 should become available, routine sales made in reliance on its provisions could be made only in limited amounts and in accordance with the terms and conditions of the Rule.  The Investor further understands that in connection with sales of securities for which Rule 144 is not available, compliance with some other exemption from registration will be required.  The Investor understands that the Company is under no obligation to the undersigned to register the Shares or to comply with the conditions of Rule 144 or take any other action necessary in order to make available any exemption for the sale of the Shares without registration.

j.           The Investor has been advised to consult with the Investor’s own attorney regarding legal, tax, and other matters concerning an investment in the Company and has done so, to the extent the undersigned considers necessary.

k.           The Investor acknowledges and is aware of the following:

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(i)           that the Shares are a speculative investment and involve a high degree of risk of loss by the Investor of the Investor'sentire investment in the Company;

(ii)          that there is no guarantee that the Investor will realize any gain from his or her investment in the Company and that the Investor may lose his or her entire investment;

(iii)         that the Company hasno current plan or intention to issue dividends with respect to the Shares;

(iv)         that there has never been any representation, guarantee or warranty made to the Investor by any broker, the Company, its agents or employees or any other person, expressly or by implication, as to:

(A)           the approximate or exact length of time that the Investor will be required to remain as owner of the Shares; or

(B)           the past performance or experience on the part of the officers or directors of the Company, or of any other person, that will in any way indicate the predictable results of the ownership of the Shares or any such other securities, or of the overall business of the Company;

v)           that the Company may in the future issue additional shares of capital stock in the Company, and that the Investor's interest in the Company may thereby become diluted.

The Investor acknowledges that he or she understands the meaning and legal consequences of the representations, warranties and acknowledgments contained in this Agreement. The Investor confirms that such representations, warranties and acknowledgments are true and accurate as of the date of this Agreement and shall be true and accurate as of the date of delivery of the Funds to the Company and shall survive such delivery. If in any respect such representations and warranties shall not be true and accurate prior to acceptance of this Agreement pursuant to Section 2 of this Agreement, the Investor shall give written notice of such fact to the Company, specifying which representations and warranties are not true and accurate and the reasons therefor.

4.           Indemnification. The Investor acknowledges that he or she understands the meaning and legal consequences of the representations and warranties contained in Section 3 of this Agreement, and the Investoragrees to indemnify, defend and hold harmless the Company and each officer, director, representative and agent of the Company and any person or entity controlling the Company from and against any and all loss, cost, damage or liability (including reasonable attorneys' fees) due to or arising out of a breach of any representation or warranty of the Investor contained in this Agreement.

5.           No Waiver. Notwithstanding any of the representations, warranties, acknowledgments or agreements made in this Agreement bythe Investor, the Investor does not thereby or in any other manner waive any rights granted to the Investor under federal and state securities law.

6.           Transferability. The Investor agrees not to transfer or assign this Agreement, or any of the Investor's interest in this Agreement, and further agrees that any assignment or transfer of the Shares shall be made only in accordance with applicable securities laws and that an appropriate legend with respect thereto may be placed by the Company on any certificate evidencing such Shares.

7.           Revocation. The Investor agrees that he or she shall not cancel, terminate or revoke this Agreement.

8.           Termination of Agreement. If any representation or warranty of the Investor contained in Section 3 of this Agreement shall not be true prior to acceptance of this Agreement, and written notice of such fact has been given by the Investor to the Company, then and in any such event this Agreement shall be null and void and of no further force and effect, and no party shall have any rights against any other party under this Agreement or otherwise, and the Company shall promptly return to the Investor the Funds together with all agreements executed by the Investor.

9.           Dispute Resolution

a.           All disputes, claims, or controversies arising out of or relating to this Agreement or any other agreement executed and delivered pursuant to this Agreement or the negotiation, validity or performance hereof and thereof or the transactions contemplated hereby and thereby that are not resolved by mutual agreement shall be resolved solely and exclusively by binding arbitration to be conducted before the American Arbitration Association (“AAA”).  If AAA ceases operation, then the parties shall select a comparable organization that provides qualified arbitration services.  The arbitration shall be held in Boston, Massachusetts before a single arbitrator and shall be conducted in accordance with the rules and regulations promulgated by AAA unless specifically modified herein.

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b.           The parties covenant and agree that the arbitration hearing shall commence within ninety (90) days of the date on which a written demand for arbitration is filed by any party hereto.  In connection with the arbitration proceeding, the arbitrator shall have the power to order the production of documents by each party and any third-party witnesses.  In addition, each party may take up to three depositions as of right, and the arbitrator may in his or her discretion allow additional depositions upon good cause shown by the moving party.  However, the arbitrator shall not have the power to order the answering of interrogatories or the response to requests for admission.  In connection with any arbitration, each party shall provide to the other, no later than seven (7) business days before the date of the arbitration hearing, the identity of all persons that may testify at the arbitration and a copy of all documents that may be introduced at the arbitration hearing or considered or used by a party’s witness or expert. The arbitrator’s decision and award shall be made and delivered within three (3) months of the selection of the arbitrator. The arbitrator’s decision shall set forth a reasoned basis for any finding of liability or award of damages.  The arbitrator shall not have power to award damages in excess of actual compensatory damages and shall not multiply actual damages or award punitive damages or any other damages that are specifically excluded under this Agreement, and each party hereby irrevocably waives any claim to such damages.

c.           The parties covenant and agree that they will participate in the arbitration in good faith and that they will share equally its costs, except as otherwise provided herein.  The arbitrator may in his or her discretion assess costs and expenses (including the reasonable legal fees and expenses of the prevailing party whether claimant or respondent) against any party to a proceeding.  Any party failing or refusing to comply with an order of the arbitrators shall be liable for costs and expenses, including attorneys’ fees, incurred by the other party in enforcing the award. Nothing in this Section 9 shall prohibit any party from proceeding in court without prior arbitration for the limited purpose of seeking a temporary or permanent injunction to avoid immediate and irreparable harm.  The provisions of this Section 9 shall be enforceable in any court of competent jurisdiction.

d.           Unless otherwise ordered, the parties shall bear their own attorneys’ fees, costs and expenses in connection with the arbitration.  The parties will share equally in the fees and expenses charged by AAA.

e.           Each of the parties hereto irrevocably and unconditionally consents to the exclusive use of AAA to resolve all disputes, claims or controversies arising out of or relating to this Agreement or any other agreement executed and delivered pursuant to this Agreement or the negotiation, validity or performance hereof and thereof or the transactions contemplated hereby and thereby and further consents to the jurisdiction of the federal or state courts of the Commonwealth of Massachusetts for the purposes of enforcing the arbitration provisions of Section 9a of this Agreement.  Each party further irrevocably waives any objection to proceeding before AAA based upon lack of personal jurisdiction or to the laying of venue and further irrevocably and unconditionally waives and agrees not to make a claim in any court that arbitration before AAA has been brought in an inconvenient forum.  Each of the parties hereto hereby consents to service of process by registered mail at the address to which notices are to be given.  Each of the parties hereto agrees that its or his submission to jurisdiction and its or his consent to service of process by mail is made for the express benefit of the other parties hereto.

10.           Miscellaneous

a.           All notices or other communications given or made under this Agreement shall be in writing and shall be delivered or mailed by (a) registered or certified mail, return receipt requested, postage prepaid, or (b) overnight air courier, fees prepaid, to the Investor at his or her address set forth below and to the Company at its address set forth at the outset of this Agreement.

b.           Failure of the Company to exercise any right or remedy under this Agreement or any other agreement between the Company and the Investor, or delay by the Company in exercising the same, will not operate as a waiver of such right or remedy.  No waiver by the Company will be effective unless and until it is in writing and signed on behalf of the Company.

c.           Notwithstanding the place where this Agreement may be executed by any of the parties hereto, all the terms and provisions hereof shall be construed in accordance with and governed by the laws of the Commonwealth of Massachusetts, without giving effect to its conflict of law principles.

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d.           This Agreement is binding upon and inures to the benefit of the parties hereto and their respective heirs, successors and permitted assigns.  This Agreement cannot be assigned, amended or modified by the parties hereto, except by written agreement executed by the parties hereto.

e.           This Agreement may be executed in one or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

f.           If any provision of this Agreement shall for any reason be held invalid or unenforceable, such invalidity or unenforceability shall not affect any other provision hereof and this Agreement shall be construed as if such invalid or unenforceable provision had never been contained herein.

g.           This Agreement constitutes the entire agreement between the parties with respect to the subject matter of this Agreement and may be amended only bya writing executed by all parties.

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IN WITNESS WHEREOF, the undersigned has executed this Agreement on this ___ day of April, 2007.

Manner in which Title is to be held (Please Check One):

1.           ___           Individual

2.           ___           Joint Tenants With Right of Survivorship

3.           ___           Community Property

4.           ___           Tenants in Common

5.           ___           Married with Separate Property

EXECUTION BY NATURAL PERSONS

Exact Name(s) in Which Title is to be Held

(If Joint Tenant or Tenants in Common, both persons must

sign and this page must contain all information for both persons).

Signature	Signature
Name (Please Print)	Name (Please Print)
Residence: Number and Street	Residence: Number and Street
City, State, Zip Code	City, State, Zip Code
Social Security Number	Social Security Number
Telephone Number

Accepted this ___ day of April 2007, on behalf of the Company.

AMERICAN DG ENERGY INC.

By:
Name:	Anthony S. Loumidis
Title:	Chief Financial Officer

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EXECUTION BY SUBSCRIBER THAT IS AN ENTITY

(Corporation, Limited Liability Company, Partnership, Trust, Etc.)

Name of Entity (Please Print)

Date of Incorporation or Organization:

State of Principal Offices:

Federal Taxpayer Identification Number:

	By:
	Title:
Attest: _________________________________	Address:
(If Entity is a Corporation)
		Taxpayer Identification Number

Accepted this ___ day of April 2007, on behalf of the Company.

AMERICAN DG ENERGY INC.

By:
Name:	Anthony S. Loumidis
Title:	Chief Financial Officer

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ACCREDITED INVESTOR QUESTIONNAIRE

Please check the box below that best characterizes the person or entity subscribing for the Shares under the terms of the foregoing Subscription Agreement.

o Any natural person whose individual net worth, or joint net worth with that person’s spouse, at the time of his purchase exceeds US $1,000,000;

o Any natural person who had an individual income in excess of $200,000 in each of the two most recent years or joint income with that person’s spouse in excess of $300,000 in each of those years and has a reasonable expectation of reaching the same income level in the current year;

o Any organization described in Section 501(c)(3) of the Internal Revenue Code, a corporation, a Massachusetts or similar business trust or a partnership, in each case, not formed for the purpose of this investment, with total assets in excess of US $5,000,000;

o Any director, executive officer, or general partner of the issuer of the securities being offered or sold, or any director, executive officer, or general partner of a general partner of that issuer;

o Any trust with total assets in excess of US $5,000,000, not formed for the specific purpose of acquiring the securities offered, whose purchase is directed by a sophisticated person as described in Rule 506(b)(2)(ii) of the Securities Act of 1933;

o Any entity in which all of the equity owners are accredited investors;

o Any private business development company as defined in Section 202(a)(22) of the Investment Advisers Act of 1940;

o Any Small Business Investment Company licensed by the U.S. Small Business Administration under Section 301(c) or (d) of the Small Business Investment Act of 1958;

o Any investment company registered under the Investment Company Act of 1940 or a business development company as defined in Section 2(a)(48) of that Act;

o Any bank as defined in Section 3(a)(2) or a savings and loan association or other institution defined in Section 3(a)(5)(A) of the Securities Act of 1933 acting in either an individual or fiduciary capacity;

o Any insurance company as defined in Section 2(13) of the Securities Act of 1933;

o Any employee benefit plan within the meaning of Title I of the Employee Retirement Income Security Act of 1974 whose investment decision is made by a fiduciary which is either a bank, savings and loan association, insurance company, or registered investment advisor, or whose total assets exceed US $5,000,000, or, if a self-directed plan, a plan whose investment decisions are made solely by persons who are accredited investors;

o Any broker or dealer registered pursuant to Section 15 of the Securities Exchange Act of 1934; or

o Any plan established and maintained by a state, its political subdivisions, or any agency or instrumentality of a state or its political subdivisions for the benefit of its employees, if such plan has total assets in excess of $5,000,000.

o None of the above.

Name of Subscriber:

Social Security Number:

Signature:

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