Optimal control of an integrated solar collector and air-source heat pump system with PCM tank

For traditional energy systems, the setpoint temperature was set following standards and codes. However, for optimizing the systems by control methods, the precondition for this was that the relationships between the setpoint temperature and system indicators were clear. For the newly designed, integrated solar collector and air-source heat pump system with PCM tank, these relationships had not been previously explored. To address this research gap, this study examined effects of different setpoint temperatures on the energy, economic, and environmental performance. The genetic algorithm was applied to conduct the optimization for maximizing comprehensive performance. An open-air swimming pool served as the case study, with a total heating load of 7.44×10 5 kWh. Each air-source heat pump in the system had a rated heating capacity of 500 kW and weighed approximately 2 tons, based on market data. Results indicated that system coefficient of performance was respectively 3.46 and 7.92 when pool water setpoint temperature during preheating period was 27°C and 31°C, increased by 129.1%. After optimization, system coefficient of performance achieved 8.92, and total melting time of PCM tank was 143.4 hours. This study offered valuable guidance for optimizing setpoint temperatures in integrated solar collector and air-source heat pump system with PCM tank.