Conventional photovoltaic panel for nocturnal radiative cooling and preliminary performance analysis

A novel concept of energy harvesting method (PV-RC) based on the conventional photovoltaic (PV) panel, combining diurnal PV conversion and nocturnal radiative cooling (RC) method, was developed to generate electricity and obtain cooling energy. A PV-RC hybrid system was also designed, manufactured, and spectral characterized, which exhibit high solar absorption in PV conversion band (0.3–1.1 μm) and has strong thermal emission within thermal radiation band (4–25 μm). Experimental studies of the hybrid system were carried out in Hefei (117° E, 32° N), China. The measured results demonstrate that the hybrid system has an average electricity output of 75.7 W m⁻² with an average electrical efficiency of 12.4% for diurnal PV conversion and exhibits an equilibrium temperature reduction of 12.7 °C below ambient temperature for nocturnal RC process. Parametric studies were also conducted by a validated simulation model, which discuss the effects of different meteorological parameters on the performance of the system. The simulated results imply that dry regions are more suitable for nocturnal RC mechanism.