Comparative analysis of anti-soiling coatings for PV modules in a tropical climate

Abstract

The accumulation of dust on photovoltaic (PV) modules significantly reduces their efficiency, making anti-soiling coatings (ASCs) an essential solution. However, comprehensive comparisons of different ASC technologies under real-world conditions remain limited. This study systematically evaluates four ASC types (surfactant, hydrophilic-photocatalyst, hydrophilic-antistatic, and hydrophobic coatings) to assess their adhesion strength, durability, anti-soiling performance, and impact on PV energy output in a tropical environment. Surface morphologies and elemental compositions of ASCs were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), while adhesion performance was examined through tape tests and contact angle measurements. The coatings were field-tested on PV modules in two distinct environments: a rooftop PV system near a mangrove area and a PV power plant near an agricultural zone, with data collected over both dry and rainy seasons. Results indicate that hydrophobic coatings exhibited the highest durability and anti-soiling efficiency, followed by hydrophilic-antistatic, hydrophilic-photocatalyst, and surfactant coatings. The hydrophobic coating also demonstrated the most significant improvement in PV energy output, making it the most effective long-term solution. Additionally, this study evaluates the environmental and economic feasibility of ASC application, highlighting the trade-offs between coating effectiveness and maintenance costs. These findings provide critical insights into selecting optimal ASC technologies for PV systems in high-soiling regions, bridging the gap between laboratory research and real-world performance.