Probing thermal dynamics in multi-layer solar photovoltaic modules: Unveiling hotspots and advancing innovative cooling strategies

Abstract

Thermal management of solar photovoltaic (PV) modules is crucial for optimizing energy efficiency, as uneven temperature distribution hinders performance. This study investigates the thermal dynamics of multi-layer PV modules comprising ethylene tetrafluoroethylene (ETFE), ethylene vinyl acetate (EVA), silicon cells, polyethylene terephthalate (PET), tape, and carbon fibre-reinforced polymer (CFRP). The study uniquely combines numerical, theoretical, and real-time experimental validation using a solar simulator under an average of 1000 W/m² to mimic the solar irradiance at standard test conditions. Numerical results revealed relatively uniform surface temperatures across layers, with the cell layer reaching the highest surface average temperature (41.36 °C) attributed to its intrinsic material properties such as high adsorption efficiency and thermal conductivity. Experimental observations showed that the frontsheet (ETFE) average temperature increased to 59.98 °C, measurable among other multi-layer surfaces. These discrepancies result in efficiency variations: numerical (15.54 %), theoretical (14.05 %), and experimental (8.94 %), with the experimental efficiency showing a 36.4 % and 42.5 % reduction compared to theoretical and simulation predictions, respectively. The theoretical model assumes idealized conditions, while experimental results reveal resistive heating effects and late-stage voltage collapse in the IV curve. To mitigate temperature-induced efficiency losses, this study advocates for innovative cooling solutions, including phase change materials, metal foam fins, and thermoelectric-based radiative cooling, enabling bottom-layer thermal regulation for continuous PV operation. These findings contribute to next-generation sustainable PV technologies, supporting affordable and clean energy (SDG 7) through optimized thermal management strategies.