Hydrogen production in solid oxide electrolyzers coupled with nuclear reactors

Abstract

In this study, two types of high temperature electrolyzers (O=SOE and H+SOE) were investigated for hydrogen generation in relation to nuclear power plant operations. The analysis encompasses the thermal integration of proton and ion conducting solid oxide electrolyzers, which are fed with steam generated in the nuclear plant. Under consideration in the study was the steam turbine cycle of an AP1000 nuclear power plant. The main parameters of electrolysis were tailored to match the typical operating temperature of the electrolyzers, and the water utilization factor was set at the same value for the two technologies under consideration. There are some advantages to applying high temperature electrolysis to the deaerator steam feed: first, there is almost no modification of the nuclear steam turbine cycle; second, flexibility of the nuclear power plant rises by 20% with almost constant thermal load of the nuclear reactor; and third, high pressure hydrogen is obtained for commercial purposes. The analysis concludes that hydrogen can be produced in electrolyzers integrated with nuclear plants at an energy cost of 38.83 and 37.55 kWh kgH2−1 for protonic and ionic solid oxide electrolyzers, respectively.