In 2004, the European Parliament and the Council of the European Union adopted the Directive 2004/8 EC whose purpose is to increase energy efficiency and develop high efficiency cogeneration of heat and power. Italy brought into force this law by means of the Legislative Decree February 8, 2007, n. 20: from January 1, 2011, the high efficiency cogeneration is the cogeneration that meets the requirements of Directive 2004/8/EC. Then, Italy adopted two ministerial decrees: the ministerial decree of Environment Ministry (August 4, 2011), that integrates the Decree n.20, and the ministerial decree of Ministry of Economic Development (September 5, 2011), that lays down the conditions and procedures for access to the support system of cogeneratio...