Innovative water-cooling system for enhanced energy efficiency in photovoltaic-thermal system

Photovoltaic (PV) panels convert solar energy into electricity but suffer from efficiency losses as panel temperatures rise. A novel photovoltaic-thermal (PVT) system integrated with a water-cooling system (WCS) was developed in this study to alleviate this issue. Most of the previous studies attach TEC directly at the back surface of the PV panel to reduce PV temperature. However, this research develops a novel design of WCS to cool the water to 20 °C before it flows into the PVT collector. Comparative performance analysis between the PVT-WCS and conventional water-based PVT systems revealed that the PVT-WCS system achieved superior electrical and thermal efficiencies. Under solar irradiance of 846 W/m2 and a mass flow rate of 0.05 kg/s, the PVT-WCS system demonstrated a 16.54 % increase in power output compared to the conventional PVT system. This enhancement is attributed to a steeper temperature gradient between the PV panel and the cooling fluid, improving the convective heat transfer coefficient and enabling more effective thermal energy removal. The PVT-WCS system achieved an overall energy efficiency of 83.26 %, outperforming the conventional PVT system of 80.02 %. The findings highlight the potential of integrating PVT with WCS to enhance energy generation and overall performance.