Parametric study of a high-performance ammonia-fed SOFC standalone system

Ammonia-fed solid oxide fuel cell (SOFC) power generation systems are very promising owing to their high efficiency and ease of fuel storage. However, understanding the complexity of fuel cell stacks and systems supplied by ammonia remains challenging. Therefore, it is proposed to investigate the standalone SOFC system to clearly elucidate the behavior of the stack and realize facile implementation. In this study, the stack was modeled and validated using experimental data to confirm its output characteristics. The system efficiency was then calculated under various operating conditions, such as current density, fuel utilization, and stack in/out temperature. The results show that the system efficiency is approximately 54 % and is highly dependent on fuel utilization and current density but not on temperature differences. However, the system can only operate at a temperature difference of 65 °C or higher owing to the effectiveness of the heat exchanger on the fuel side.