Molten Salt Fast Microreactors

Naarea (France) is developing the XAMR, a 40 MW molten salt fast microreactor that uses spent nuclear fuel from conventional reactors as its feedstock. In September 2025, the company demonstrated a proliferation-resistant pyrochemical method for producing its sodium chloride-plutonium trichloride fuel salt — a critical milestone proving the waste-to-energy concept works at a chemical level. The reactor produces both 40 MW of electricity and 80 MW of heat.

The XAMR represents a different philosophy from other European SMR designs. While Nuward (EDF) miniaturizes conventional pressurized water reactors and Newcleo pursues lead-cooled fast reactors, Naarea combines Generation IV molten salt and fast neutron technologies into a compact, transportable unit. The molten salt approach eliminates the risk of meltdown — the fuel is already liquid — and the fast neutron spectrum can transmute long-lived radioactive waste into shorter-lived isotopes, reducing the nuclear waste problem rather than adding to it.

Naarea partnered with Phoenix Manufacture for mass production using 3D printing and precision engineering techniques — applying France's aerospace manufacturing heritage to nuclear reactor components. The compact XAMR design is intended to be factory-built and transported to sites, serving industrial facilities, military bases, or remote communities that need reliable baseload power without connection to major grids. Deployment is targeted for the early 2030s.