Study of the influence of dust deposits on photovoltaic solar panels: Case of Nouakchott

Abstract

Degradation performance of photovoltaic (PV) modules by real weather conditions has become increasingly problematic. In the desert climate, dust accumulation is one of the main concerns that may cause a significant deterioration of PV efficiency. In the present work, experimental investigations were carried out to understand the effect of dust on the electrical performance of PV modules under Toujounine, Nouakchott, Mauritania weather conditions. The measurements were performed with an I-V tracer ftv200. The measured parameters were I-V and P-V curves, open-circuit voltage (Voc), short-circuit current (Isc), current and voltage at maximum power (Imp and Vmp) and maximum power (Pmax); as well as the measurement of temperature of panels and Irradiation. The study was carried out according to the following cleaning scenarios: panels cleaned before each measurement (Clean panels 01), panels undergoing systematic cleaning with the central unit (Clean panels 02) and chains undergoing no cleaning (Dusty panels 03). Then, the modeling of reliability as a function of maximum power by Weibull's law, for clean and dusty panels is evaluated. According to the experimental results, disturbances in I-V and P-V curves for dusty panels were noticed. Also, a decrease in the Isc and the Imp for dusty panels compared to clean panels was found. These results are explained by the effect of dust accumulation on the module's surface, which blocks the solar radiation and thus reduces the conversion efficiency of PV modules. Again, dust reduces the output power of photovoltaic modules by 21.57% for dusty panels per clean panels. Finally, a low reliability for dusty panels compared to clean panels was found, due to the loss in the output power under the dust effect. These results clearly show the importance of properly maintaining and servicing the photovoltaic modules to avoid their degradation by dust deposits.