Hybrid Sulfur Cycle

The hybrid sulfur cycle, or HyS, is a two-step water-splitting process intended for hydrogen production. Based on sulfur oxidation and reduction, it is classified as a hybrid thermochemical cycle because it uses an electrochemical reaction, rather than a thermochemical one, for one of its two steps; the remaining thermochemical step is shared with the sulfur-iodine cycle. The hybrid sulfur cycle was initially proposed and developed by the Westinghouse Electric Corporation in the 1970s, which is why it is also known as the Westinghouse cycle, and current development efforts in the United States are led by the Savannah River National Laboratory.