Numerical simulation and experimental verification of solar PVT coupled PEM electrolyzer system for hydrogen production

Hydrogen production by electrolysis of water is the key to the future of hydrogen fuel production. This study proposes a hydrogen production system based on the thermoelectric demand for proton exchange membrane electrolyzers (PEMEs) and the characteristics of the thermoelectric output of photovoltaic (PV) thermal (PVT) systems. The proposed system combines PVT and PEME to realize thermoelectric hydrogen–oxygen multiproduction and establishes and validates the thermoelectric coupled numerical model used for the prediction of the operating characteristics of the PVT-PEME system. Furthermore, it investigates and compares the irradiation intensity, ambient temperature, and inlet flow rate of the PVT-PEME and PV-PEME systems, and estimates the operating characteristics of the PVT-PEME system in different climates. The results show that the electrolyzer energy efficiency tends to increase and then decrease with increasing irradiation intensity; the PVT-PEME efficiency increases with increasing ambient temperature; and the PV-PEME efficiency decreases with increasing ambient temperature. Moreover, the efficiency of the electrolyzer decreases with an increase in the inlet flow rate, but the PVT-PEME efficiency increases. The high temperature inhibits the performance of PV modules, which is promoted in PEME after heat exchange in the PVT system, improving the operating efficiency. In addition, an evaluation of the actual operating characteristics of the PVT-PEME hydrogen production system in different climates indicates that the system operated for shorter and less efficient times when operating at cold and low irradiation intensities.