High-Temperature Gas-Cooled Reactors

HTGRs use helium gas to remove heat from the reactor core, which consists of graphite moderator and fuel particles embedded in ceramic coatings. The high operating temperatures of HTGRs allow for efficient electricity generation and the production of high-temperature process heat for industrial applications. The use of helium as a coolant eliminates the risk of coolant boiling and provides inherent safety features. Supply chain considerations involve the availability of specialised fuel particles, graphite materials, and high-temperature components. Logistical challenges include the transportation and installation of large reactor components. Accessibility for developing countries is limited by the high cost and technical complexity associated with HTGR technology.

While the fundamental technology is proven, HTGRs are still in the testing and demonstration phase, with ongoing efforts to improve their performance and reliability.

HTGRs have inherent safety features, such as passive decay heat removal and a low probability of core meltdown. However, the use of graphite as a moderator requires careful management to prevent graphite oxidation and potential radiological releases.

HTGRs use proliferation-resistant fuel designs, but the potential for producing plutonium in spent fuel requires security measures to prevent unauthorised access and ensure proper control of nuclear materials.

IAEA safeguards are essential for HTGRs, involving inspections, material accounting, and containment and surveillance measures to verify the peaceful use of nuclear materials.