Development of intermediate temperature SOFC module and system

Abstract

The third-generation 1kWe-class module was developed with an automatic control system. A conversion efficiency of 48% [AC/LHV] was achieved with an exhaust heat recovery unit. An endurance test using the third-generation 1 kWe module has been done for over 1000 hours and no degradation in the power generation performance was observed. In parallel, a single cell unit, which includes one cell and two metallic separators, was tested for over 6000 hrs and the degradation rate of the terminal voltage was found to be 1 - 2%/1000 hr. For scale up, a triple-stack 3 kWe module was developed. A partial load as well as excess loads on the module were tested and the output power of 1 - 5 kWe was attained with thermally self-sustainable conditions. A high efficiency of 55% [DC/LHV] was obtained under stable operation. On-going research of the fourth-generation 1 kWe module has resulted in the conversion efficiency of 58% [DC/LHV].