Experimental comparison of PDMS and PVB coatings on photovoltaic panels in terms of radiative cooling and transparency: First report for PVB

Implementing radiative cooling for photovoltaic (PV) cells involves intricate challenges, such as optimizing selective coatings for efficient thermal emission, managing atmospheric variables like humidity and cloud cover, and integrating advanced materials without compromising structural integrity or light absorption. Additionally, ensuring cost-effectiveness and scalability remains a critical concern for widespread adoption. This study experimentally explores the coatings of polydimethylsiloxane (PDMS) and polyvinyl butyral (PVB) on photovoltaic panels in terms of radiative cooling and transparency, as well as simulates the problem using the COMSOL Multiphysics package. The present comparative analysis includes three distinct photovoltaic panel configurations: (i) a standard commercial panel, (ii) a panel coated with PDMS, and (iii) a panel coated with PVB. The selective layers of PDMS and PVB contribute to heat emission toward the sky, resulting in a reduction of the final temperature relative to the commercial structure. These results demonstrate the radiative cooling effect of both the PVB and PDMS layers. In addition, the panels coated with these layers demonstrate better light transmission than the standard commercial panel without coating. However, the findings reveal that the PVB layer has markedly superior transparency within the solar spectrum compared to the PDMS layer, enhancing light transmission in the PVB-coated structure. In summary, the research indicates that while the cooling ability of PDMS is slightly higher than that of PVB, the light transmission capability of PVB is significantly better than that of PDMS. Additionally, PVB is more cost-effective and can be applied on a larger scale than PDMS, making it a promising material for enhancing the performance and lifespan of photovoltaic panels.