This review provides a comprehensive assessment of cooling paint approaches to enhance the efficiency and longevity of photovoltaic (PV) modules. The main cooling paint approaches are categorized as reflective, radiative, and hybrid cooling paints. Reflective cooling paints like TiO 2 - and BaSO 4 -based cooling paints are effective in reducing operating temperatures and improving solar reflectance with possible efficiency retention of 2–3%. Radiative cooling paints are characterized by high solar reflectance and high infrared emittance to ensure cooling in the night and restricted thermal cycling with possible cooling of up to 7.2 °C to ensure improved longevity of PV devices. Hybrid cooling paints are designed to ensure effective cooling in the daytime and nighttime with improved cooling of up to 15.6 °C; some studies also reported possible relative efficiency improvements of 29.6%. Although these cooling paints have shown improved efficiencies and cooling effects, they are limited by factors such as photoaging by UV radiation, durability in the outdoors and soiling effects, scalability to real-world PV systems, and the complexity between emittance and cost-effectiveness. This review also identifies some research gaps in conducting full-scale testing of cooling paints.
Alao et al. (Tue,) studied this question.