Fast Breeder Reactor Technology

A fast breeder reactor uses fast neutrons (unlike thermal reactors that slow neutrons) to cause fission in fuel and, crucially, to convert fertile material (U-238 or Th-232) into fissile material (Pu-239 or U-233). The result is that the reactor "breeds" more fuel than it consumes, making it a critical technology for countries with limited uranium but large thorium reserves.