Investigation of operation optimization of cchp and water source heat pump compound energy supply systems

Abstract

Several studies and applications have explored combined cooling, heating, and power systems (CCHP) and water source heat pump systems, but the compound operation of these systems have not been sufficiently investigated. The majority of investigations on CCHP system optimization are based on economic, energy quantity, or energy level perspectives. These different optimization objectives provided varied results. The author introduces an optimization method that takes exergetic cost as optimization objective to couple energy cost, energy quantity, and energy level into a comprehensive indicator that integrates optimization results. The quantities of import and export energy are calculated based on the mathematical models including exergetic cost, CCHP system, and water source heat pump system. The systems' exergetic cost is then compared and analyzed under the external constraint conditions to determine the operation strategy. Finally, the optimization method is applied to the compound energy supply system of Danzishi centre business district (CBD) CCHP plant station in Chongqing China. Results show that the exergetic cost of operation of the compound system is 0.103 US dollar/kWh in summer and 0.088 dollar/kWh in winter, which are lower than the water source heat pump and closer to that of the CCHP system. Primary energy utilization rate (PER) in summer is 1.40 and 0.92 in winter. These findings verify the capability of the method to help the CCHP and water source heat pump compound systems achieve good energy efficiency and economy performance. The investigation develops the theoretical method and reference for the practical application of operation optimization and performance research of CCHP and relative compound energy supply systems.