An On‐Demand Safety Gas Generator for Solid Oxide Fuel Cell and Electrolyzer Systems

Abstract

With their high electrochemical efficiency, solid oxide fuel cells (SOFCs) and solid oxide electrolyzers (SOEs) offer viable means of reducing energy sector greenhouse gas emissions and storing surplus renewably‐generated power. At present, these systems have operating temperatures of over 600 °C. During start‐up, following cooling or in an emergency shut‐off situation, a premixed safety gas is necessary which prevents damage to the cell's anode substrate. To date, safety gas has been industrially produced and stored in compressed gas cylinders. Given an SOFC system's size, these cylinders must be transported and stored in close proximity and replaced following gas expenditure. The storage space required, as well as the continuous replacement of gas cylinders, increases system size and costs. This paper presents a solution to this problem in the form of a specially developed safety gas generator that generates an on‐demand synthetic safety gas via the system's infrastructure. The functionality of this component is experimentally validated in tests conducted with a 4‐cell stack.