Optimization and year-round trigeneration performance analysis of the photovoltaic thermal heat pump system: a case of engineering application

To enhance the stability of the photovoltaic thermal heat pump (PVT-HP) system in engineering application, and identify its year-round trigeneration performance for refrigerating, heating, and power generation to provide a design foundation for its applications in engineering application, the PVT-HP system was optimized and replaced in a practical engineering, and then its year-round stability and trigeneration performance were experimentally studied. The results illustrated the stability performance evaluation indicators including the fluctuation range of the discharge and suction pressures, discharge temperature, and superheat under all working conditions were within the range of −2.5 %–5.0 %, 3.0–8.0 °C, and 40.0–85.0 °C, respectively, proving that the optimized system has superior stability performance. The thermal efficiency, electrical efficiency, heating COP, and exergy efficiency of the optimized system were 239.4 %, 10.6 %, 5.9, and 12.4 %, respectively, in summer; The transitional seasons are 73.6 %, 11.2 %, 5.1 %, and 14.8 %, respectively; In winter, they are 56.0 %, 12.4 %, 3.7 %, and 17.5 %, respectively. Furthermore, the refrigerating quantity and COP were 15.7 kW and 3.6, respectively, on summer nights. The optimized system exhibited refrigerating and heating COPs that were elevated by a range of 20.0 %–85.0 % compared to current studies, demonstrating remarkable performance in refrigerating and heating. Additionally, the life cycle cost of the optimized system was significantly reduced, falling short of other technological approaches by 7.0 %–70.0 %, indicating the optimized system has superior economic advantages.