Performance of a PV module as influenced by deposition of desert dust with consideration of “Thermophoresis” in dust layer

This paper is aimed at calculating the current-voltage (I-V) and power-voltage (P-V) curves of a PV module operating in dusty atmosphere using a proposed lambert-function based method. The method is based on module parameters, which are obtained using the datasheet values of the module. The propagation of the incident radiation on the module surface is tracked through the module layers including dust layer, glass cover and module cells to evaluate the intensity of radiation received at the cells surface being less intense than the incident one. This reflects its self on reducing the short-circuit current and the output power of the module. The cell temperature of the dusty module is evaluated -for the first time-based on the concept of “thermophoresis” under the thermal gradient developed across the dust layer. Such layer is sand-witched between ambient temperature $T_{a}$ and cell temperature $Tc_{clean}$. The difference $Tc_{clean}-T_{a}$ is related to the thickness of dust, the intensity of radiation received at the cell surface and the dust density on module surface. The cell temperature is also evaluated based on a known formula including ambient temperature, incident radiation and normal operating cell temperature quoted from the module datasheet. Both approaches for evaluating cell temperature are considered in determining the I-V and P-V curves. The obtained results are discussed and correlated to those published in the literature.