Hybrid thermochemical water splitting cycles are provided in which thermally reduced metal oxides particles are used to displace some but not all of the electrical requirements in a water splitting electrolytic cell. In these hybrid cycles, the thermal reduction temperature is significantly reduced compared to two-step metal-oxide thermochemical cycles in which only thermal energy is required to produce hydrogen from water. Also, unlike the conventional higher temperature cycles where the reduction step must be carried out under reduced oxygen pressure, the reduction step in the proposed hybrid cycles can be carried out in air, allowing for thermal input by a solar power tower with a windowless, cavity receiver.
Patent Number: US9279188B2
Diver, Richard B. Jr; Palumbo, Robert D.; Siegel, Nathan P.; and Miller, James E., "Hybrid metal oxide cycle water splitting" (2016). Other Faculty Research and Publications. 137.