Cogeneration is used to produce electricity and heat at the same time within a single system starting from one fuel source, either fossil or renewable. The production of electricity and heat with separate processes generally does not permit use of the heat produced by the combustion process, which is released into the atmosphere.
Cogeneration instead includes the recovery and use of the heat produced by the combustion process, guaranteeing a more efficient use of the primary combustion source.
A valid example of a cogeneration application is the production of electricity with a generating set composed of an engine coupled to an alternator. The heat generated by the engine combustion process is conveyed and used by a heat generator for the production of heat in the form of carriers.