Improvement of Solar Panel Efficiency Using a Water Circulation System: An Experimental Study

This study aims to address the problem of thermal degradation that negatively affects the efficiency of photovoltaic (PV) panels in hot environments in Baghdad, Iraq. The research provides a practical evaluation of a low-cost, closed-cycle water cooling system, designed using aluminum tubes mounted on the back surface of the panel to promote heat exchange. To ensure the accuracy of the results, a real-time comparison was made between two identical polycrystalline panels (20 W), one with the proposed cooling system and the other with an uncooled reference panel, under the same climatic conditions. The results demonstrated that the system effectively reduced the operating temperature by 20-25 °C compared to the reference panel. This thermal reduction reflected positively on electrical performance, as the output power increased by 16.1%, and the overall efficiency increased from 7.99% to 9.28%. This study confirms the technical and economic feasibility of the proposed cooling system as a sustainable solution to raise solar energy productivity in regions with hot climates.