Economic assessment of hydrogen production from solar driven high-temperature steam electrolysis process

The optimum energy efficiency of a PV driven process increases from 9.1% at 873 K, 1500 A/m2 to 12.1% at 1273 K, 8000 A/m2. For the electrolyzer operating at 873 K, the optimum LCOH2 of 22 $/kg is obtained at 6000 A/m2. For the electrolyzer temperature of 1073 K, LCOH2 drops from 16 $/kg at 5000 A/m2 to 12.1 $/kg at 10000 A/m2. When compared to PEME, this route becomes viable beyond 973 K, 6000 A/m2 for PV and 923 K, 3000 A/m2 for CSP driven processes. With the current state of economics, this process is not competitive with the industrial steam methane reforming route. However, the cost target of 6-8 $/kg is achievable if the component costs reduce to 2030 level. Thus, the process has potential to be commercially viable and should be pursued further by creating prototype and pilot scale demonstrations.