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Pressurized Heavy Water (CANDU)

Heavy Water family · Generation II / III · Commercial

Settled science

Uses heavy water so efficiently that it can run on unenriched natural uranium and refuel while operating.

How it works — schematic
🚧 Diagram in progress
Containment Calandria vessel Calandria Heavy water (D₂O) Steam generator Steam Turbine G ⚡ grid Condenser
Heavy water lets it run on natural uranium.

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

Key specs

Coolant
Heavy water
Moderator
Heavy water
Fuel
Natural uranium
Spectrum
Thermal
Outlet temp
~310 °C
Status
Commercial

Real-world examples

  • • CANDU fleet (Canada, India, others)
Strengths
  • + No enrichment needed
  • + Online refueling
  • + Fuel flexibility
Trade-offs
  • – Expensive heavy water
  • – Larger core
  • – Tritium production