Cogeneration

n. generation of electric power and heat using a combined system

Cogeneration (also combined heat and power, CHP) is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat.Conventional power plants emit the heat created as a byproduct of electricity generation into the environment through cooling towers, as flue gas, or by other means. CHP or a bottoming cycle captures the byproduct heat for domestic or industrial heating purposes, either very close to the plant, or - especially in Scandinavia and eastern Europe - for distribution through pipes to heat local housing.
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The consecutive generation of useful thermal and electric energy from the same fuel source.

Production of two useful forms of energy such as high-temperature heat and electricity from the same process. For example, while boiling water to generate electricity, the leftover steam can be sold for industrial processes or space heating.