Overview of high temperature gas-cooled reactor

A high temperature gas-cooled reactor (HTGR) is a nuclear reactor that can supply high temperature heat energy of 750°C–950°C by using a spherical fuel coated with ceramics such as carbon and silicon carbide, inert helium gas as a coolant, and graphite as a moderator. At present, a light water reactor is mainly used for nuclear power generation, but HTGR is attracting attention mainly for the following two reasons: the first reason is that the nuclear heat should be used for fields other than power generation, because fossil fuels and renewable energy have a limit to meet the increasing energy demand in the future. The second reason is excellent safety. Among all reactor types, HTGR has excellent inherent safety and its safety has been demonstrated in experimental reactors. This chapter explained the features of HTGR such as structure, heat application, and the history of development.