Annual report pursuant to Section 13 and 15(d)

Description of Business

v2.4.0.6
Description of Business
12 Months Ended
Dec. 31, 2011
Description of Business [Abstract]  
Nature of Operations [Text Block]
DESCRIPTION OF BUSINESS
Ameresco, Inc. (including its subsidiaries, the "Company") was organized as a Delaware corporation on April 25, 2000. The Company is a provider of energy efficiency solutions for facilities throughout North America. The Company provides solutions, both products and services, that enable customers to reduce their energy consumption, lower their operating and maintenance costs and realize environmental benefits. The Company's comprehensive set of services includes upgrades to a facility's energy infrastructure and the construction and operation of small-scale renewable energy plants. It also sells certain photovoltaic equipment worldwide. The Company operates in the United States, Canada and Europe. 
The Company is compensated through a variety of methods, including: 1) direct payments based on fee-for-services contracts (utilizing lump-sum or cost-plus pricing methodologies); 2) the sale of energy from the Company's generating assets; and 3) direct payment for photovoltaic equipment and systems.