Optimization of BCHP Schemes Based on GRA and AHP

BCHP (Building Cooling, Heating and Power) system is an integrated energy system based on the energy cascade utilization and is used to supply heating, cooling and power synchronously. Normally the scale of BCHP system is smaller than that of the CCHP (Combined Cooling Heating and Power) system of thermal power plant. BCHP system is one of the most important directions of the second generation energy system and distributed energy system and has advantages of energy conservation, environment protection and safety performance, etc. In this paper with the example of an actual building, by using the theories of GRA (Grey Relation Analysis) and AHP (Analytical Hierarchy Process) the mathematical models for the comprehensive evaluation of BCHP system are established. Three schemes of BCHP systems are given and the indexes of economy, environment protection, energy conservation and reliability are considered as the main factors in the project selection of BCHP system. The optimal scheme is selected according to the cooling, heating and power loads of the building. In the optimization process, both the evaluation indexes and the weight coefficients are chosen objectively to improve the comprehensive and scientific performance of BCHP project selection.