The effect of dust on transmission and self-cleaning property of solar panels

Abstract

While how to improve the efficiency of solar cells is commonly researched, the effect of dust-fall on solar cell efficiency in the local Singapore weather has been largely neglected. In this work we investigated the conditions affecting dust-fall in Singapore and its effect on the optical transmission through glass modules. It was found that for bare glass samples, transmission reduces despite the heavy rains in Singapore over several months. After 33 days, transmission through plain glass slides reduced from 90.7% to 87.6%. Samples located nearer sources of dust and other contaminant particles such as heavy traffic, were more adversely affected compared to those which were situated in greenery. We also investigated the effect of substrate tilt in keeping them clean. Bare glass substrates were tilted at angles of 0, 10, 20, 30, 40, 50, 60, 70, 80 and 90 degrees during outdoor exposure. The transmission through the lower parts of the substrates tilted at a fixed angle, was generally worse than the upper part as dust is washed downwards. After 33 days, the average transmission through the upper part of sides was 88.7%, while through the lower part it was 87.9%. We also investigated the performance of TiO 2 films as an outdoor self-cleaning coating for solar panels. TiO 2 films of different thicknesses were deposited on glass substrate by hydrolysis method which is a low-cost and commercially viable process. We will present the outdoor performance of TiO 2 films, and discuss the optimised film parameters for solar cell applications. © 2011 Published by Elsevier Ltd.