Co-generation, also known as combined heat and power (CHP), describes the simultaneous production of both useful heat (that can be used, for example, in industrial processes or city heating schemes) and electricity in a single process or unit. Co-generation enables much greater plant efficiencies to be obtained in terms of energy conversion with overall efficiencies as high as 80-90 %. The energy savings potential of co-generation is important with regard to reducing emissions and improving energy efficiency.