Microreactors

Microreactors are designed to be compact and transportable, allowing for deployment in remote locations or areas with limited infrastructure. They typically use solid or liquid metal coolants and operate at low power levels. Microreactors can be factory-fabricated and transported to the deployment site, minimising on-site construction. Supply chain considerations involve the availability of specialised fuel, coolants, and reactor components. Logistical challenges include the transportation of radioactive materials and the management of spent fuel. Accessibility for developing countries is enhanced by the modular design and simplified operation, but technical expertise for maintenance and fuel handling is still required.

Microreactors are in the testing and demonstration phase, with ongoing efforts to develop and deploy these innovative reactors.

The nuclear safety risks associated with microreactors are related to direct exposure to radiation and contamination through the release of radioactive materials into the environment. This can be due to malfunctions or accidents, or the mismanagement of radioactive waste or spent fuel. Microreactors have inherent safety features, such as passive decay heat removal and a low probability of core meltdown. Nevertheless, robust safety systems and regulations are essential to minimise the nuclear safety risks.

Stringent security measures are essential to ensure proper control and prevent, detect or respond to theft, sabotage, unauthorized access, illegal transfer or other malicious acts involving the nuclear fuel, other radioactive material or the nuclear facility itself. The deployment of microreactors, particularly in remote locations may present unique security challenges.

The applicable IAEA safeguards agreement will be implemented, involving, for example, inspections, nuclear material accounting, and containment and surveillance measures, to verify the peaceful use of nuclear materials. Sealed reactor cores, long fuel cycles, factory-based manufacturing and transport across international borders, remote locations and novel fuel forms are some of the safeguard challenges for microreactors. “Safeguards by Design”, incorporating built-in sensors and inspection access points into the design, will facilitate the implementation of safeguards during operation.