Combined Heat & Power: CHP Present & Future

Abstract

Combined Heat and Power (CHP) is an efficient way to generate electricity and heat by utilizing the waste heat from the electric generator in place of heat from a separate boiler. Currently, most electricity is purchased from a central utility company that generates power at 35% efficiency; the balance of fuel input energy is lost as heat. With CHP some of the electricity is generated onsite and the waste heat from the generator (water jacket and exhaust) is used for space and water heating and other industrial processes that require heat. This reduces the fuel requirements to the boiler which also reduces emissions of Green House Gases (GHG) and other pollutants. Overall CHP efficiencies can make upwards to 85%. CHP is also known as Buildings Cooling, Heating & Power (BCHP), CHP for buildings (CHPB), Integrated Energy Systems (IES), Total Energy System (TES), Tri-generation (Trigen) and Cogeneration. CHP is best fit where there is demand for heat (or cooling load) and electricity is simultaneous e.g. hospitals, the hotel industry, educational institutes. Exhaust heat can be applied to support cooling loads with absorption chillers.