lead-cooled fast reactor

nuclear physics

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July 21, 2026

Quick Summary

A lead-cooled fast reactor is a type of breeder reactor designed to produce more fissionable material than it consumes. This allows for more efficient use of nuclear fuel, particularly uranium-238, which is abundant but less readily fissionable than uranium-235.

Fast breeder reactors, including lead-cooled variants, use high-speed neutrons to split plutonium nuclei, releasing heat and more neutrons to sustain a chain reaction. This heat is then used to generate electricity. While liquid-metal fast breeder reactors (LMFBRs) often use sodium as a coolant, other proposed designs, such as lead-cooled fast reactors, utilize different materials for heat transfer.12

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breeder reactor
Fast breeder reactors
with helium, and sodium-cooled and lead-cooled fast reactors. Additionally, a supercritical water fast reactor has been proposed that would operate at a supercritical pressure to utilize fluid water that is neither steam nor liquid.
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with helium, and sodium-cooled and lead-cooled fast reactors. Additionally, a supercritical water fast reactor has been proposed that would operate at a supercritical pressure to utilize fluid water that is neither steam nor liquid.
Read More