Of all the high-temperature applications, there is probably maximum interest in hydrogen at the present time. Hydrogen production is an important long-term objective of the Generation IV Programme.

The challenge is to develop a hydrogen generation process that does not release greenhouse gas such as carbon dioxide (Institute of Nuclear Engineers, 2004). The classical fossil fired steam reformation of methane has this problem and methods of reducing the CO2 release are under development. Other techniques being investigated include high-temperature electrolysis and also thermo-chemical water splitting. Neither of these methods produce CO2.

The generation of hydrogen using nuclear heating is under consideration within the JAERI HTTR programme described below. Hydrogen production technology is also being considered within the US Next Generation Nuclear Plant programme at Idaho.