Thermal management matters in photovoltaic–electrocatalysis for solar hydrogen production

Photovoltaic–electrolysis (PV-EC) system currently exhibits the highest solar to hydrogen conversion efficiency (STH) among various technical routes. This perspective shifts the focus from the materials exploration in photovoltaics and electrolysis to the critical aspect of thermal management in a PV-EC system. Initially, the theoretical basis that elucidates the relationships between temperature and the performance of both photovoltaics and electrolyzers are presented. Following that, the impact of thermal management on the performance of PV-EC for solar hydrogen production is experimentally demonstrated by designing variables-controlling experiments. It is observed that while utilizing identical PV and EC cells under varying thermal conditions, the highest STH can reach 22.20%, whilst the lowest is only 15.61%. This variation underscores the significance of thermal management in optimizing PV-EC systems. Finally, increased efforts to enhancing heat transfer and optimizing heat distribution are proposed, thus facilitating the design of more efficient PV-EC systems with minimized thermal energy losses.