Full-spectrum solar water decomposition for hydrogen production via a concentrating photovoltaic-thermal power generator-solid oxide electrolysis cell system

Abstract

This study introduces a novel solar-powered concentrating photovoltaic-thermal power generator-solid oxide electrolysis cell system designed to enhance hydrogen production efficiency by optimizing both electrical and thermal energy utilization. The system incorporates a thermal power generator to convert excess high-temperature thermal energy into electrical energy, addressing energy losses associated with high-temperature water electrolysis. Thermodynamic analysis shows that the integration of the thermal power generator improves energy and exergy efficiencies to 0.60 and 0.52, while lowering the optimal operating temperature to 1173 K. The system’s efficiency is sensitive to the proportion of electrical energy supplied by the thermal power generator, with an optimal range identified between 0.1 and 0.2. Higher temperatures improve hydrogen production and efficiency, but increased voltage negatively impacts thermodynamic efficiency. These findings demonstrate that the proposed system offers substantial improvements over conventional solar hydrogen production methods, making it a promising candidate for sustainable hydrogen production. Further research will focus on system integration, material costs, and scalability for commercial use.