Power performance of high density photovoltaic module using energy balance model under high humidity environment

Abstract

In this study, the temperatures of high-density PV modules (HDMs) were predicted by considering the effect of relative humidity. First, factors that could affect the module temperature were analyzed. It was found that humidity affects the Prandtl number, the thermal conductivity between the module and air, and the viscosity of air. Experiments were performed to confirm that the PV module temperature increases as the relative humidity increases. The differential equation of the energy balance model was solved by considering the relative humidity to verify the accuracy of module temperature prediction during indoor and outdoor experiments. A MAPE of (0.8843[%]) and an RMSE of (0.45) were obtained for the indoor experiment. With regard to the outdoor experiment, both MAPEnatural and MAPEtotal were measured separately. The most accurate prediction was obtained for the month of April, with MAPEnatural and MAPEtotal values of (0.216[%]) and (0.1197[%]), respectively. The most inaccurate prediction considering MAPEnatural, which had a value of (1.698[%]), was obtained for December. Furthermore, the most inaccurate prediction considering MAPEtotal, which had a value of (0.485[%]), was obtained for August. The most accurate prediction considering RMSEnatural (2.605) was obtained for June, and that considering RMSE total (2.223) was obtained for December. The most inaccurate prediction considering RMSEnatural (5.785) was obtained for November, and that considering RMSEtotal (3.093) was obtained for April. These predictions were accurate only when natural and forced convection were considered. In summary, relative humidity affects the atmosphere around the PV module and the module temperature, thereby affecting the power performance of the PV module.