original_query: What is the integral fast reactor (IFR) and how does it differ from other nuclear reactors?
query: What is the integral fast reactor (IFR) and how does it differ from other nuclear reactors?
answer: The Integral Fast Reactor (IFR) is a nuclear reactor design using fast neutrons and no moderator.  Key differences from other reactors include its on-site fuel reprocessing via electrorefining (making it 'integral'), its use of metallic fuel, its liquid sodium coolant (allowing for near ambient pressure operation), and its inherent safety features (demonstrated by self-shutdown in simulated accidents).  The IFR is designed for higher fuel efficiency and significantly reduced radioactive waste compared to traditional light water reactors (LWRs).