Future Hydrogen Production Using Nuclear Reactors

The potential of hydrogen to replace fossil fuels presents a significant opportunity for reducing greenhouse gas (GHG) emissions, especially when hydrogen is produced by "water-splitting", instead of hydrocarbon processing. "Water- splitting" by energy derived from nuclear sources is a preferred method for "carbon-free" production of hydrogen on a large scale. Researchers around the world are pursuing two new ways of water-splitting - thermochemical cycles and high- temperature electrolysis (HTE), using thermal energy from the future generation of higher temperature reactors. Both these methods, when coupled with a high-temperature nuclear reactor, could have efficiencies in the range of 50-60% compared to <30% for conventional electrolysis - currently the only existing method of producing hydrogen without co-product CO₂. Research is underway at Atomic Energy of Canada Limited (AECL) on the development of the next generation of advanced CANDU^reg concepts that include the Supercritical Water-Cooled Reactor (SCWR). The SCWR would use supercritical water as the coolant with a nominal outlet temperature of up to 6251 and could deliver heat at ges550degC for hydrogen production. AECL is currently evaluating various thermochemical cycles and high-temperature electrolysis for matching with the temperature capability of the SCWR and ACR-1000^reg.