Experimental and optimization study of photovoltaic panel thermal management using serrated fins and biomass-derived hybrid conductive PCM

This study presents a novel passive cooling system for photovoltaic (PV) panels, integrating serrated fins with shape-stabilized phase change materials (SS-PCMs) enhanced by a biomass-derived hybrid filler composed of walnut shell charcoal and graphene nanoplatelets. The hybrid filler improves thermal conductivity and prevents PCM leakage, while the serrated fins enhance heat transfer. Experiments under varying solar irradiance (300–1000 W/m 2 ) assessed the effects of irradiance, filler weight fraction (0–10 wt%), and fin number (0–8) on PV surface temperature and electrical efficiency. Results show that the combination of fins and hybrid fillers significantly reduces PV temperature and improves heat dissipation uniformity. The optimal configuration—8 fins with 10 wt% filler—achieved a maximum temperature reduction of 24.82 °C compared to an uncooled panel, increasing electrical efficiency by 1.45% (absolute). Response Surface Methodology (RSM) revealed strong correlations between design parameters and performance, identifying solar irradiance as the most influential factor. Multi-objective optimization determined the best operating condition at 800 W/m 2 irradiance, yielding a PV temperature of 43.52 °C, 14.67% efficiency, and a desirability of 0.911. These findings demonstrate that combining serrated fins with biomass-enhanced SS-PCMs provides a synergistic passive cooling effect, delaying thermal saturation and improving PV system performance and durability.