FBR
Fast Breeder Reactor
Fast breeder reactor (FBR) breeds more fissile material than it consumes using fast neutrons without moderator.
Breeding ratios >1.0 with Pu-239 or U-238; Russia's BN-800 (880 MWe) uses MOX fuel. Pool or loop sodium coolant common. ~20 GWth experience globally.
Why it matters now
FBRs address uranium scarcity via breeding; Russia's BN-800 supports 2025 closed fuel cycle amid HALEU bottlenecks.