Influence of Manual Cleaning on the Thermal Behavior of Photovoltaic Modules

Our study investigates soiling effects on photovoltaic (PV) modules operating temperature (T<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub>) in an urban PV plant in Brazil. Our experiments were carried out over an 18-month period under different environmental conditions and manual cleaning intervals varying between 7 and 35 days. T<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> measurements were recorded at the center and edges of both clean and dirty modules. The results indicate that clean modules present slightly higher T<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> values than dirty ones, with a statistically significant difference confirmed by the application of the t-test, but without substantial impact on the plant operation. Furthermore, as the no-cleaning interval increases, the thermal gradient between the center and the inferior edge tends to reduce, while the gradient between the superior and inferior edges exhibits nonlinear behavior, suggesting distinct phases of soiling deposition. This research contributes to understanding soiling influence on PV module thermal behavior, with implications for optimizing PV efficiency in urban environments..