A hybrid photovoltaic-thermoelectric generator system with temperature-controlled pump flow for enhanced energy efficiency

Balancing cooling flow rate and pump power consumption is the key challenge in water-cooled photovoltaic systems. In this study, a photovoltaic panel, thermoelectric generator, and composite heat sink were arranged in a sandwich configuration to form a water-cooled hybrid system, and experiments were conducted at 40%, 70%, and 100% flow rates. Based on the fixed-flow results, an intelligent control group was established using a temperature–flow control rule, whereby the pump flow rate is adjusted in real time according to the monitored photovoltaic panel temperature. The experimental results demonstrate that after 60 min of operation under the metal halide lamp, the three fixed-flow groups reduced the average photovoltaic panel surface temperature by 67.7 °C, 70.1 °C, and 72.8 °C, respectively, relative to the reference photovoltaic panel. Correspondingly, the photovoltaic panel power output increased by 38.5%, 46.5%, and 49.3%, while the hybrid system average photoelectric conversion efficiency improved by 46.65%, 52.39%, and 43.32%. Compared with the 100% flow group, the intelligent control group achieved a comparable temperature reduction of 71 °C and a photovoltaic panel power output increase of 49.1%, while reducing pump power consumption by 23% and attaining the highest average system efficiency improvement of approximately 53.29%. This study provides an energy-efficient solution for flow control in water-cooled photovoltaic applications.