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This paper presents a radiative/convective hybrid heat dissipation photovoltaic-thermal heat pump (HHD-PVT-HP) refrigeration system based on the traditional PVT solar heat pump, which can be used to meet the cooling demand of buildings. PVT modules are used for the system condenser. The PVT modules emit heat to the ambient surroundings (hybrid heat dissipation) mainly by two ways: radiation to the night sky and convection with the surrounding air. An experimental study and parametric analysis of the HHD-PVT-HP system is conducted. The experimental results indicate that the HHD-PVT-HP system is able to stably refrigerate on summer night, with an average COPref value ranging from 1.8 to 2.1. Moreover, the heat dissipation performance of the PVT modules is good, with an average hybrid heat dissipation flux of ∼420 W/m2. To predict the operation characteristics of the HHD-PVT-HP under various ambient conditions, a system simulation model is established and validated with experimental data. The simulation results show that changes in the ambient air temperature and wind velocity have obvious effects on the heat dissipation characteristics of the PVT modules and system refrigeration performance. However, when the outdoor wind velocity is greater than 1 m/s, its influence is obviously lessened. Additionally, the relative humidity of the ambient air has little effect on the refrigeration capacity and COPref of the HHD-PVT-HP system.

Photovoltaic thermal heat pump technology stands for the combination of solar heat pump technology and a photovoltaic system, which has the characteristics of tri-generation (heating, cooling, and electricity) to meet the building's energy requirement. In this paper, the dual-use photovoltaic thermal heat pump system was used and investigated experimentally with an emphasis on the refrigeration mode, which with the feature of the novel roll-bond photovoltaic thermal unit working as condenser directly. Moreover, renewable energy such as solar radiation and long-wave radiation are the main energy source of this system. The experimental investigation of the system comprising; 4 roll-bond photovoltaic thermal units, 1 horsepower heat pump unit and 600 L ice storage tank was carried out. The performance evaluation method and uncertainty analysis of the system was proposed and implemented along with the examination on the refrigeration performance and operating characteristics of the system. The results indicate that the proposed photovoltaic thermal heat pump system can achieve the refrigeration for building space cooling demand in summer with high performance and long-term stable operation. This study could provide a valuable reference for the photovoltaic thermal heat pump multi-generation system design and large-scale practical application in northern China.