Very-High-Temperature Reactor (VHTR)

 

 

The Very-High-Temperature Reactor (VHTR) is a graphite-moderated, helium-cooled reactor with a once-through uranium fuel cycle. It supplies heat with high core outlet temperatures which enables applications such as hydrogen production or process heat for the petrochemical industry or others.

The VHTR system is designed to be a high-efficiency system that can supply process heat to a broad spectrum of high-temperature and energy-intensive, non-electric processes. The system may incorporate electricity generating equipment to meet cogeneration needs. The system also has the flexibility to adopt uranium/plutonium fuel cycles and offer enhanced waste minimization. Thus, the VHTR offers a broad range of process heat applications and an option for high-efficiency electricity production, while retaining the desirable safety characteristics offered by modular high-temperature gas-cooled reactors.

The Next Generation Nuclear Plant (NGNP) prototype concept employs the VHTR concept, and is based on what is judged to be the lowest risk technology development that will achieve the needed commercial functional requirements to provide an economically competitive nuclear heat source and hydrogen production capability. The reference concept includes a helium-cooled, graphite moderated, thermal neutron spectrum reactor. The reactor outlet temperature will be in the range of 850 to 950ºC. The reactor core technology will either be a prismatic block or pebble bed concept. The NGNP will produce both electricity and hydrogen using an indirect cycle with an intermediate heat exchanger to transfer the heat to either a hydrogen-production demonstration facility or a gas turbine.

The objectives of the NGNP are to (1) demonstrate safe and economical nuclear-assisted production of hydrogen and electricity, (2) demonstrate the basis for commercialization of the nuclear system, the hydrogen production facility, and the power conversion concept, and to (3) establish the basis for Nuclear Regulatory Commission licensing of the commercial version of NGNP.