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.

光伏（PV）模块在实际天气条件下的降解性能变得越来越成问题。在沙漠气候中，灰尘堆积是可能导致PV效率大幅下降的主要问题之一。在目前的工作中，进行了实验研究以了解粉尘对Toujounine，Nouakchott，毛里塔尼亚的天气条件下的PV组件的电气性能的影响。使用IV示踪剂ftv200进行测量。测量的参数为IV和PV曲线，开路电压（Voc），短路电流（Isc），最大功率下的电流和电压（Imp和Vmp）和最大功率下（Pmax）；以及面板温度和辐照度的测量。该研究是根据以下清洁方案进行的：每次测量前都要清洁面板（清洁面板01），使用中央单元进行系统清洁的面板（清洁面板02）以及不进行清洁的链条（多灰尘面板03）。然后，根据魏布尔定律评估了清洁和多尘面板的可靠性与最大功率的函数关系。根据实验结果，发现粉尘面板的IV和PV曲线存在干扰。此外，发现粉尘面板的Isc和Imp减少了。这些结果可以通过灰尘在模块表面的积聚来解释，灰尘会阻挡太阳辐射，从而降低了PV模块的转换效率。同样，对于每块干净的面板，灰尘可以使多尘面板的光伏模块的输出功率降低21.57％。最后，由于灰尘效应下输出功率的损失，发现与干净的面板相比，灰尘较多的面板的可靠性较低。这些结果清楚地表明了正确维护和维护光伏模块，以避免其因灰尘沉积而退化的重要性。