Shahrood University of Technology Renewable Energy Research and Applications 2717-252X Articles in Press 2026 07 22 Experimental Assessment of Aluminum Heat Sink Geometries on Temperature Mitigation and Power Output in PV Panels under Natural Convection 3862 10.22044/rera.2025.16795.1464 EN Radin Ahmadi Mechanical Engineering Department, Shahrood University of Technology, Shahrood, Iran Ali Sarreshtehdari Mechanical Engineering Department, Shahrood University of Technology, Shahrood, Iran Journal Article 2025 09 12 Photovoltaic (PV) panels experience efficiency losses from elevated operating temperatures, particularly in high-insolation regions where overheating reduces power output and module lifespan. This issue is exacerbated in arid climates like Iran, where abundant solar resources coincide with extreme heat, emphasizing the need for cost-effective passive cooling. Prior research focuses on active cooling or wind-assisted methods, overlooking natural convection under stagnant conditions and the use of commercially available materials. To address these gaps, this study evaluates the thermal and electrical benefits of repurposing industrial aluminum profiles as heat sinks for PV panels, offering a sustainable solution using off-the-shelf components without custom fabrication. Experiments used a controlled laboratory setup with a monocrystalline PV panel under 1000 W/m² irradiation and zero wind speed. Three aluminum profiles, varying in mass and geometry, were attached to the panel's rear and compared to an uncooled reference. Measurements included time-dependent surface temperatures, power outputs and thermal imaging, with uncertainty analysis for reliability. Findings indicated time-dependent effects: during the initial heating phase (0-30 minutes), heat sinks reduced temperatures (up to 2.56°C for the heaviest model) and increased power (up to 1.65%). In the stabilization phase (30-60 minutes), temperatures exceeded the reference (by 0.25-1.57°C), causing slight power drops (0.67-1.24%). Heavier profiles delayed stabilization but risked hot air entrapment. These time-dependent effects underscore the potential of aluminum heat sinks for modest PV performance improvements in zero-wind conditions, albeit with trade-offs in long-term stability. These findings emphasize the importance of geometry selection for enhancing natural convection efficiency in stagnant-air PV applications.