Basic Study of Two-Stage Solid Oxide Fuel Cell Stacks with Fuel Regenerator

Two-stage stack technology is a method to generate highly efficient power using fuel cells. To achieve highly efficient power, it is important to regenerate anode gas between the two-stage stacks. The effect on power generation efficiency by removing H2O and/or CO2 from the anode gas using a fuel regenerator has been investigated by simulating the two-stage solid oxide fuel cell stack model. The risk of carbon deposition from regenerated anode gas has also been investigated by calculating the equilibrium state of the anode gas. The maximum efficiency of net AC 71.8% (lower heating value) was obtained when H2O and CO2 were 100% removed from the anode gas, assuming that thermal self-sustainability in the system was achieved.