Heat and Hydrogen Co-Production based on Photoresponsive Electrode in the Full-Spectrum SOEC Hybrid System

Facing the growing demand for clean and efficient energy conversion, this study presents the first full-spectrum SOEC hybrid system that co-produces heat and hydrogen by integrating a photoresponsive electrode. The electrode is directly irradiated to generate an additional photocurrent, thereby boosting hydrogen yield, while spectral splitting technology simultaneously supplies the SOEC with both heat and electricity. A comprehensive modeling framework, including the SOEC, balance of plant, and solar photoresponsive models, is developed to evaluate system energy and water flow and to analyze factor interactions within the photoresponsive material. Under optimized conditions, the system achieves an exergy efficiency of 58.98%, a solar-to-hydrogen (STH) efficiency of 28.30%, and a solar-to-thermal (STT) efficiency of 43.78%, offering new theoretical insights and practical design rules for highly efficient, flexible full-spectrum solar hydrogen production.