CHP can be configured as a topping or bottoming cycle. In the topping CHP system, the fuel is combusted in a primer mover like a reciprocating engine, combustion or gas turbines, fuel cells, etc., that drives the whole system to generate electricity. The bottoming cycle is also called “waste heat to power (WHP),” where the fuel is combusted to provide thermal input to a furnace or other industrial process. The heat that is not used for the process is used to produce electricity.