cogeneration

Cogeneration is basically the production of energy and usable heat (generally in the form of steam and hot water) in the same plant, usually by capturing heat that in older plants used to be simply wasted. It's one of the principal ways in which countries intend to reduce their greenhouse-gas emissions so as to slow climate change. Cogeneration plants are often small, and the fuels used in them are varied. Lumber mills, for instance, can operate their own cogeneration plants, feeding them with wood scraps and sawdust, and wastewater treatment plants generate gas that can likewise be used as a source of energy. Since it's hard to move heat long distances, cogeneration is most efficient when the heat can be used nearby. Though the general public today knows little about cogeneration, more and more of us will be benefiting from it in the coming years.