Fatores de perdas causados por sujidade nos sistemas fotovoltaicos instalados nas unidades da Universidade Federal do Triângulo Mineiro

Abstract

The photovoltaic system is promising because it relies on a clean and abundant resource: solar radiation. However, the accumulation of dirt on the surface of photovoltaic modules is one of the main factors that decrease their efficiency. This study, conducted at the ICTE (Institute of Technological and Exact Sciences) campus of the Federal University of Triângulo Mineiro, in Uberaba-MG, aimed to verify the effect of dirt on the efficiency of photovoltaic modules. For this, climatic parameters and electrical characteristics of the modules were collected and measured, comparing strings of dirty and clean modules. The interference of dirt on the efficiency of photovoltaic modules was confirmed through various measurements in scenarios of clean and dirty modules, evidencing an efficiency loss. The present study revealed that the accumulation of dirt reduced the efficiency of the modules by up to 7.50% after seven months of exposure. The temperature difference between a dirty module and a clean one reached 8.9%. In all measurements, both the operating current and the generated power were higher in clean modules. This confirms that the presence of dirt particles reduces the transmittance of the module surface, causing a considerable efficiency loss. Therefore, adopting a periodic cleaning schedule for photovoltaic power generation systems can yield significant benefits over time. Financially, UFTM is missing out on approximately 35.37% savings on the amounts charged by the local utility company (CEMIG), which represents about R$25,391.81 per year with the current system. With a system capable of supplying the entire ICTE consumption, losses could reach R$29,453.22 per year. From an economic point of view, it is essential to optimize the cleaning of photovoltaic modules to maximize their efficiency and prolong their lifespan.