Cogeneration is a system that produces heat and electricity simultaneously in a single plant, powered by just one primary energy source, thereby guaranteeing a better energy yield than would be possible to achieve from two separate production sources. In this way, nearly all the thermal energy produced by combustion processes is not dissipated into the environment, as happens with traditional plants, but is recovered and reused. The most widely used cogeneration technologies involve the combustion of fuels such as natural gas, GPL, diesel, biogas, bio-methane, vegetable oil or biomass.