Cogeneration is the combined production of heat for use in industrial facilities and the production of electricity as a by-product. Electricity not used within the plant may be offered to the competitive electricity market. Combined use of heat in production and to generate electricity improves the overall efficiency of the plant and can displace higher emissions coal-generated electricity. Treatment of cogeneration under the Specified Gas Emitters Regulation recognizes these environmental benefits associated with the higher energy efficiencies generally afforded by cogeneration operations.