Radiation regulation of silicon photovoltaic modules for effective thermal management: A potential analysis

Enhancing the radiative cooling capacity or reflecting all the sub-bandgap photons to realize effective thermal management has elicited great interest. Numerous related investigations of the enhancement have been covered in literature, while the photoelectric conversion along with the working conditions still exhibit significant variability, and the mechanisms through enhancing heat dissipation or suppressing heat generation are entirely distinct. Herein, a comprehensive potential analysis is conducted on the radiation regulation technologies. Building upon our simulation framework, a modified thermal network with refined fifteen nodes that cover the entire structure of the PV module is integrated, enabling precise determination of the temperature trend. Accordingly, the basic properties of the PV module and the energy distribution are calculated, along with the power change of heat generation and dissipation of the module. The optimization mechanisms behind the temperature decline are revealed, and the practical temperature reductions under different working conditions are determined for reference. The results reveal that, for a silicon PV module, the radiation regulation scheme through rejecting all the non-contribution solar photons can eliminate below bandgap loss and suppress parasitic absorption and is much more efficient than enhancing its radiative cooling capacity. The average temperature reductions can reach up to 2.86 °C, 3.75 °C, and 4.60 °C respectively by rejecting all non-contribution photons compared to the original module with the incoming solar irradiance intensity of 600, 800, and 1000 W/m2, while the values decrease to 0.68 °C, 0.77 °C and 0.86 °C if only the emissivity is improved to unity, and further drop to 0.64 °C, 0.70 °C and 0.78 °C if the sub-bandgap reflection capacity has been improved. Additionally, all the performance enhancements will be diminished with the wind speed, and enhancing emissivity is more suitable to be applied in hot environment, whereas reflecting useless photons prefers cold.