Research Progress on Solar Photovoltaic Thermal (PV/T) Systems

Solar photovoltaic solar thermal (PV/T) comprehensive utilization technology combines photovoltaic cells with solar collectors, so the system can not only convert solar energy into electricity, but also effectively collect and use heat energy, improving the efficiency of solar heat utilization. At present, there are many types of PV/T technology in the world. According to the cooling method, PV/T technology can be divided into air-cooled PV/T technology, liquid cooled PV/T technology and other types of technology. Solar photovoltaic (PV/T) systems with liquid and air as heat transfer media cool photovoltaics by convection. In order to improve the stability of the fluid, the water medium can be replaced by nanofluids, and the concentration of nanofluids can be increased to increase the thermal conductivity. Mixed nanofluids have good heat transfer performance, and different kinds of nanoparticles have different effects on the stability and thermal conductivity of PV/T systems. The PCM can keep the temperature change relatively stable, and the thermal conductivity of PCM can be improved by adding metal filler, metal array structure, metal fin tube and aluminum cutting sheet. Heat pipes can solve the PV/T freezing problem in cold areas to improve the thermal/electrical efficiency of PV/T systems. By summarizing the current related research, we know that the PV/T collector cooling technology needs to be further studied, including: the optimization and improvement of traditional air-cooled water-cooled PV/T system. Considering the influence of different mixtures of nanofluids on PV/T properties, the dynamic theoretical study of the influence of the stability of nanofluids and the fluctuation of external factors on PV/T systems is studied.