Techno-Economic Analysis of Reversible and Paired Solid Oxide Cell Systems for Hydrogen Production

Abstract

The use of green hydrogen to decarbonize the U.S. economy has been steadily gaining commercial interest as the cost and availability of renewable electricity decreases. At present, technologies can only take advantage of low electricity prices at low capacity factor, due to its intermittent availability, negatively impacting the economics. Reversible solid-oxide cell (r-SOC) based energy conversion systems can potentially solve this problem by producing power when electricity prices are high and hydrogen when they are low. However, the long-term operation of r-SOC systems has not been fully investigated compared to paired SOFC and SOEC units. This paper presents techno-economic results for two SOC-based hydrogen and power co-generation concepts. These technologies primarily generate hydrogen through solid oxide electrolysis but have the capacity to switch to power if signaled by the market. This operational flexibility provides a significant benefit to an electric grid with a growing share of variable renewable energy generation.