Cogeneration refers to the generation of both electricity and heat from a power plant. This improves the overall efficiency of the power plant. The efficiency of such plants can reach 85%.
In an normal power plant driven by a boiler and a turbine, all the thermal heat is not converted into electricity. This heat is recovered in a cogeneration plant. This heat can be used for industrial process and also for domestic heating in places which are cold.
In plants driven by steam turbines, the hot steam is used to drive the turbine. The outlet steam of the turbine is then used to heating homes.