Advanced Modular Reactor 

AMRAdvanced Modular Reactor is the name given to a reactor type based on Generation IV and newer technologies that are smaller than conventional nuclear power station reactors. As with small modular reactors (SMRs), they are designed to be built in modules in a factory, before being transported to the generating site. They aim to offer advances in safety, efficiency, sustainability and economics. These AMR Generation IV technologies are still in an early stage of development. The Nuclear Innovation and Research Office (NIRO) performed a technical assessment of six AMR technologies: high-/very-high temperature gas reactors; sodium-cooled fast reactors; supercritical water-cooled reactors; gas-cooled fast reactors; lead-cooled fast reactors; and molten salt reactors.

The UK government is funding an AMR research, development and demonstration programme that aims to demonstrate high-temperature gas reactor (HTGR) technology by the early 2030s, in time for any potential commercial AMRs to support net zero by 2050. The successful organisations for Phase B funding were announced at the end of July 2023.

For more information on AMR, see:
Advanced Modular Reactors Technical Assessment –

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