Impact of Textured Surfaces and Cleaning on Solar Panel Glass Transmittance

In outdoor conditions, solar panels face several factors that prevent optimal operation through lowered absorbed light intensity. Luckily, steps can be taken to minimise their effect. In this work we focus on two of these steps: panel cleaning to reduce impact of soiling and textured glass surfaces to improve transmission of high incidence angle light. Removing soiling is relatively simple task, but how do the cleaning chemicals impact the anti-reflection coating on the surface of the solar panel glass? To test this, we apply a series of common cleaning chemicals to the surface of solar panel glass pieces and measure how the transmittance of solar panel glass samples changes. The results suggest that the glass coatings can be safely cleaned using most cleaning liquids, with the exception of dishwashing detergent. The second section of this study investigates how well textured solar panel glass surfaces can improve transmittance on high light incidence angles. Earlier studies suggest that increased haze and light-trapping of a textured glass surface can be used to guide more light to the solar cell when the light source is in a large angle from the panel surface normal, but our results demonstrate that flat glass surface outperforms textured surfaces on all incidence angles.