The effect of dust deposition on photovoltaic modules

The effect of dust settlement on the efficiency of photovoltaic modules was measured. To gain a deeper insight into the problem the physical properties of the collected dust were examined using a scanning electron microscope (SEM). A potential solution for the phenomenon, namely the usage of special coatings on the cover glass, was investigated. The results show a constant power loss between 3% and 4% for the optimal tilt angle and regular rainfall. Rain seems to have little cleaning effect on smaller dust particles (<;10 μm), but on bigger particles (like pollen, ~60 μm) the effect was clearly visible.