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Molten Salt Reactor / LFTR

Molten Salt family · Generation IV · Pre-commercial (lab-proven 1960s)

Opinion / advocacy

Fuel is dissolved in a liquid salt, so the reactor runs at near-atmospheric pressure and can refuel online. The thorium LFTR is the best-known concept. Proven at lab scale at Oak Ridge; no commercial unit yet.

How it works — schematic
🚧 Diagram in progress
Containment Reactor vessel Salt core Freeze-plug drain tank Molten fuel-salt Heat exchanger Steam Turbine G ⚡ grid Condenser
Liquid fuel; a freeze plug drains it if power is lost.

Simplified schematic for orientation, not an engineering drawing — we're actively refining these for accuracy.

Key specs

Coolant
Molten fluoride/chloride salt
Moderator
Graphite (or none)
Fuel
Fuel dissolved in salt (U / Th)
Spectrum
Thermal or fast
Outlet temp
~650–700 °C
Status
Pre-commercial (lab-proven 1960s)

Real-world examples

  • • ORNL MSRE (1965–69, historic)
  • • ThorCon
  • • Terrestrial Energy IMSR
  • • Kairos (salt-cooled)
Strengths
  • + Low pressure
  • + Strong passive safety (freeze plug)
  • + Online refueling
  • + Thorium fuel option
Trade-offs
  • – Corrosive salts
  • – No commercial precedent
  • – Fuel-salt reprocessing immature