Cogeneration

Cogeneration is the simultaneous generation of two forms of energy, usually heat and electricity, from one energy source. Traditional energy generating systems produce only heat or electricity by burning a fuel source. In both cases, burning the fuel generates a lot of heat and the exhaust gases can be hotter than 932°F (500°C). Traditionally, this "waste heat" would be vented into the environment for disposal. Cogeneration facilities capture some of that waste heat and use it to produce steam or more electricity. Both systems produce the same amount of energy but cogeneration uses about 35% less fuel because it is designed to be a highly efficient process.

Cogeneration is widely used in some European countries, such as Denmark and Italy, where fuel costs are particularly large. In the United States, where fuel costs are relatively small, cogeneration produces about 5% of the energy supply. Some researchers estimate that if all large U. S. industrial plants used cogeneration technology, there would be enough energy-generating capacity to last until 2020 without building any new power plants.