Power-to-Hydrogen: Process Modeling and Thermodynamic Analysis of High Temperature Solid Oxide Electrolysis

Water electrolysis can transform the unstable renewable energy into the hydrogen energy and realize large-scale and seasonal energy storage, which is an important method to achieve the goal of "carbon neutralization". In this paper, the technology of solid oxide electrolysis cell was discussed and its working principle was introduced. According to its actual operation characteristics, the electrochemical model and thermodynamic model of electrolysis process were established. Furthermore, the influence of current density and the operating temperature on the electrolysis process were analyzed and the thermodynamic analysis was conducted. The results show that the thermal integration and management of SOEC at high temperature will be conducive to reducing the power consumption; if the high-temperature electrolysis process is combined with other industrial processes and utilized the low-grade industrial waste heat, the overall efficiency of solid oxide electrolysis is expected to be further improved.