Integral Fast Reactor

The integral fast reactor, or IFR, originally called the advanced liquid-metal reactor, is a design for a nuclear reactor that uses fast neutrons and no neutron moderator, cooled by liquid sodium and fueled by a uranium-plutonium metallic alloy. It is distinguished by a nuclear fuel cycle that reprocesses fuel on site through electrorefining, allowing it to breed more fuel than it consumes. The design was begun by the United States Department of Energy and Argonne National Laboratory in 1984, its prototype the Experimental Breeder Reactor II demonstrated passive safety tests in 1986, and the project was canceled by the United States Congress in 1994 despite ranking first in a 2002 Generation IV evaluation by a 242-person scientific team; a commercial version, the S-PRISM, has since been developed by GE Hitachi Nuclear Energy.