Modelling the regional effect of transmittance loss on photovoltaic systems due to dust

Abstract

The regional differences and environmental challenges are key factors in measuring the efficiency of renewable systems. The loss of transmittance due to weather events, such as dust, clouds/rain, extreme heat, and humidity, is one of the main factors causing reduction in energy generation from photovoltaic (PV) systems’ ideal energy production potentials. Existing literature analysed the impact of transmittance loss due to dust on PV systems’ performances, recommending frequent system cleaning to maintain the highest energy production level. In this paper we build a mathematical model to quantify the effect of dust accumulation on the transmittance losses. The model predicts the transmittance losses of PVs at tilts between 0° and 90°, exposed to Kuwait’s climate with and without cleaning. We use the model to analyse the performance of recommended tilts for optimum energy production (overall and seasonal) based on Kuwait’s geographical location. The results demonstrate that the recommended regional optimum tilt (30°) for maximum energy generation is applicable only if the system is cleaned at least once a week. Tilts of 50° and higher can perform better when the frequency of cleaning is once every two weeks or less. This is an important observation that can guide the design, installation, and maintenance (frequency of cleaning) of the PV systems.