Improving the Outdoor Performance of Silicon Photovoltaic Modules Using Ambient-Curing Antireflective Coatings

Abstract

Most photovoltaic modules are currently fabricated using heat-treated glass coated with antireflective layers. However, although such coatings increase the power output of crystalline silicon modules by 2-3% under standard conditions, commercially fabricated photovoltaic modules with antireflective coatings suffer from progressive soiling and degradation of antireflective layers caused by ultraviolet irradiation or chemical reactions, with its extent depending on various environmental conditions. Importantly, simple surface cleaning of the thus soiled modules with water cannot recover the initial performance of their antireflective coatings. To find a solution to this problem, we herein analyze the effect of re-coating modules at laboratory and field conditions with ambient-curing silica-based antireflective agents, revealing that the average power output of the thus treated modules increases by 2.6 similar to 3% compared to that of modules stripped of their antireflective coatings. Thus, although the lifetime of antireflective coatings cannot be precisely estimated, the above re-coating strategy can effectively restore or even increase the power output of soiled modules.