A transient thermal model for flat-plate photovoltaic systems and its experimental validation

Abstract

This paper describes a transient thermal model that accurately predicts the temperature of the open-rack mounted photovoltaic (PV) modules under varying atmospheric conditions. The PV module temperature is predicted by considering the thermal energy exchange between the PV module and its environment through the main heat transfer paths. The proposed thermal model has been validated by utilising data from the experiment: the temperature measurement of two identical PV modules operating in two different modes (open-circuit and full-load) was performed by means of three temperature sensors placed on the back surface of both PV modules. The model accuracy is 3 C of measured temperature values 100 % of the time under all conditions. The highest accuracy is obtained when the solar irradiance is subject to less fluctuation. The influence of the load level relative to the nominal power of the PV module on its temperature is hereby subject to consideration.