**EXHIBIT 10.8**

**AMENDMENTNO. 3**

 

**THISAMENDMENT TO FACILITIES AND SUPPORT SERVICES AGREEMENT** iseffective as of January 1, 2009 between Tecogen Inc., a Delawarecorporation (“Tecogen”), and American DG Energy Inc., a Delawarecorporation (“ADG Energy”).

 

NOW, THEREFORE, for good and valuable consideration,the receipt and sufficiency of which is hereby acknowledged, the parties herebyreaffirm all of the provisions of the Facilities and Support ServicesAgreement, dated  January 1, 2006(the “Agreement”), except that the following paragraphs shall be substitutedfor the corresponding paragraphs in the Agreement.

 

**1.****             Officeand Infrastructure**

 

Tecogen will provide toADG Energy the following office and infrastructure support services for aperiod from the date of this Agreement through the Termination Date (as suchterm is defined in Section 2 below):

 

**(a)****           Office Space.**Approximately 2,702 allocated square feet of space in Tecogen’s offices locatedat 45 First Avenue, Waltham, Massachusetts 02451 (the “Building”), whichshall include six (6) offices, a shared conference room and manufacturingspace. Tecogen will also provide ADG Energy with water, sewer, electrical,phones and other utility services, heating, ventilation and air-conditioning,and cleaning and janitorial services. Tecogen may change the space in theBuilding occupied by ADG Energy from time to time during the term of thisAgreement. Tecogen will provide such space and services at a flat rate of$4,838.00 per month. If additional space is provided, this flat fee willincrease at an annual rate of $17.72 per square foot for any additional officespace and $16.68 per square foot for any additional manufacturing space. Copymachine usage, office supplies, and shipping, secretarial &receptionist services, Internet service, telephone support and IT support arenot included in the monthly rate and will be billed separately.

 

**(c)****           Insurance and EmployeeBenefit Plans.** To the extent it is able to do under its then current plansand policies, Tecogen will include ADG Energy as a covered entity under itsliability, property and casualty, workers compensation and other applicablebusiness insurance policies. Tecogen will allow ADG Energy employees toparticipate in Tecogen’s medical and dental insurance plans, and other groupinsurance plans for its employees, including life, AD&D, and short andlong-term disability plans. The costs of these insurance programs will becharged to ADG Energy on an actual cost basis when available, or in the case ofgeneral insurance be allocated to ADG Energy for it’s pro rata share of thepremiums. Management of the plans will be carried out jointly by both companiesand with no charge to each other.

 

**(g)****          ****Exclusivity:** ADG Energy shall be granted exclusiverepresentation rights to the Tecogen Cogeneration Product in the New EnglandStates, and Tecogen shall be granted exclusive representation rights to the ADGEnergy Cogeneration Product in California. The relevant portions of Tecogen’sstandard rep agreement shall apply except where in conflict with thisagreement. ADG Energy will be eligible for split commissions for cogenerationand chiller products as presented in Tecogen’s standard rep agreement.

 

**2.****            ****Term**

 

Theterm of the Agreement, as amended hereby, commenced as of the effective datefor one year, renewable annually upon mutual written agreement.

 

INWITNESS WHEREOF, the parties hereto have caused this amendment to be dulyexecuted and delivered by their proper and duly authorized representatives asof the day and year first above written.

 

Dated:January 2, 2009 (but effective as set forth above).

 
| TECOGEN  INC.             |   | AMERICAN  DG ENERGY INC.  |
|---------------------------|--------|---------------------------|
|                      |   |                      |
| By:  /s/ Robert A. Panora |   | By:  /s/ Barry J. Sanders |
| Title:  President         |   | Title:  President         |

 

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