Applied Thermal Engineering, cilt.279, 2025 (SCI-Expanded)
Photovoltaic (PV) panels often experience reduced electrical efficiency due to high operating temperatures, making effective cooling techniques critical for performance enhancement. This study investigates the overall performance of a water-cooled photovoltaic-thermal (PVT) system featuring a novel cooling tube design aimed at increasing the contact surface area between the PV module underside and cooling tubes to improve heat transfer. To achieve this, conventional circular tubes were modified into an elliptical shape with a flat surface to enhance thermal contact. Accordingly, the performance of the designed PVT system has been experimentally examined at different conditions and compared with a PV panel with the same specifications. Additionally, overall behavior of the PVT system has been numerically simulated and compared with experimental one. Experimentally obtained results exhibited successful design of the PVT system when compared to standalone PV panel. The highest electrical efficiency for the standalone PV obtained as 16.13 %. The maximum electrical efficiency for the PVT system achieved as 17.57 %. Additionally, the highest overall efficiency of the PVT was obtained as 69.38 %. Moreover, average deviation between numerically and experimentally achieved results obtained as 3.2 %. These findings indicate the potential of the proposed cooling tube design to enhance the thermal and electrical performance of PVT systems.