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 and 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 cogeneration). From January 1, 2011, the legislative and incentive cogeneration context is radically changed and, consequently, new boundary conditions must be taken into account in order to evaluate performance of cogeneration plants. Therefore, in this paper authors have analysed the different types of plants in operation in Italy and have calculated the percentage of electricity from cogeneration of each type of plant, taking into account the typical operating parameters. The result of this paper may therefore be a valuable tool for the operators of the cogeneration sector in order to identify the suitability of an investment in this sector. (C) 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license.