Investigating the impact of aluminum heat sinks on passive cooling of photovoltaic panels

As the temperature of photovoltaic panels rises, a drop in electrical conversion efficiency and output power is unavoidable. Therefore, a simple and low-cost cooling solution is needed - one that requires little or no maintenance and consumes no electricity. In this paper, we experimentally and numerically investigated passive cooling of photovoltaic panels using heat sinks of different geometries. Our experiments showed that these heat sinks reduce the average back-side temperature of the cooled panel by 13.6°C compared to a reference panel. They also increased the open-circuit voltage by 0.27 V relative to the reference. We also performed numerical simulations using Ansys Fluent 2025 R2. The simulated temperatures agreed well with the experimental data - the average difference was less than 1°C (approximately 1.9% relative difference). The simulations gave us a good insight into heat dissipation from the heat sinks. They revealed better cooling due to proper fin spacing, but also a limitation caused by the small contact area between the heat sink and the photovoltaic panel. These results confirm that passive cooling with aluminum heat sinks is a good method for improving photovoltaic panel performance, while the developed numerical model represents an accurate tool for heat sink design optimization.