Recycling-Based Passive Cooling of PV Panels Using Copper and Aluminum Waste Particles: An Experimental Study

The performance of photovoltaic (PV) modules decreases as operating temperatures rise, particularly under high solar irradiance during summer months. Passive cooling techniques, which operate without external energy input, offer an effective and low cost way to control module temperature and improve electrical output. This study experimentally evaluates two waste based passive cooling materials (aluminum shavings and thin copper fins) mounted on the rear surfaces of PV modules. Three identical 100W monocrystalline panels were tested simultaneously under the same environmental conditions. The first panel was a reference panel, the second panel was coated with aluminum shavings, and the third panel was equipped with thin copper fins recovered from waste capacitor components. These recycled materials were selected for their low cost, availability and high surface area to volume ratio, enabling enhanced convective heat transfer. Temperature, solar irradiance, voltage, current and electrical power were recorded in real time using a custom data acquisition system. During peak radiation hours, the aluminum and copper cooled panels exhibited temperature reductions of approximately 5°C and 8°C, respectively, compared with the reference panel. Correspondingly, the copper cooled panel achieved up to a 5% increase in daily energy output, while the aluminum cooled panel produced a 2–3% improvement. Overall, the results show that lightweight and recyclable passive cooling elements can significantly enhance PV performance without increasing structural load or energy consumption, offering a practical solution for sustainable PV operation in warming climates.