American DG Energy Inc. (American DG Energy) distributes, owns and operates clean, onsite energy systems that produce electricity, hot water, heat and cooling. Its business is to own the equipment that it installs at customers� facilities and to sell the energy produced by these systems to the customers on a long-term contractual basis. The Company calls this business the American DG Energy OnSite Utility. The Company also distributes and operates water chiller systems for building cooling applications. As of December 31, 2009, the Company had installed energy systems, representing approximately 4,210 kilowatts (kW), 33.5 million British thermal units (MMBtu�s) of heat and hot water and 2,200 tons of cooling. American DG Energy purchases energy equipment from various suppliers. The primary type of equipment used is a natural gas-powered, reciprocating engine provided by Tecogen Inc. (Tecogen).