级联式太阳能光伏光热热泵系统在多种运行模式下的全年运行性能分析

Abstract The photovoltaic-thermal heat pump (PVT-HP) systems, which concurrently generate electricity and thermal energy, offer a comprehensive sustainable solution for building energy demands. This research presents the design, fabrication, and experimental performance evaluation of a novel cascade PVT-HP system incorporating 48 PVT modules, aiming to achieve efficient domestic hot water supply and residential heating applications. The experimental setup was employed to assess the thermal and electrical cogeneration performance of the PVT-HP, along with the heating performance of the CO 2 (R744) HP. The PVT-HP demonstrates exceptional annual cogeneration performance for domestic hot water production, supported by 27 representative experimental cases spanning diverse seasons. A typical spring-day case was chosen to demonstrate its considerable heating performance, which reached an average coefficient of heating performance (COP) of 6.0. In this circumstance, the average heat gain factor (HGF) and electrical efficiency were 0.75 and 20.3 %, respectively. Annual electrical output analysis further confirms the superior electrical output of PVT modules over conventional PV modules. Moreover, the integration of a transcritical CO 2 HP in this system enables the direct production of high-temperature (>90 °C) hot water, facilitating flexible operation across multiple modes to ensure year-round stable hot water supply. These findings highlight the feasibility and substantial potential of the proposed cascade PVT-HP system as an efficient and low-carbon distributed energy solution for residential applications, delivering both high-grade heat and electricity generation.