Dust-induced shading on photovoltaic modules

The effect of dust on photovoltaic (PV) modules is investigated with respect to concentration and spectral transmittance. Samples were collected in the form of raw dust as well as accumulated dust on exposed sheets of glass at different tilt angles. Spectral transmittance of the samples was determined. Transmittance variation between top, middle and bottom was identified for samples collected at different inclinations, where the worst case was seen at a tilt angle of 30o with a non uniformity of 4.4% in comparison to 0.2% for the 90o tilt. The measured data showed a decrease in transmittance at wavelengths