Critical Minerals in Context

Fusion uses lithium and specialty conductors but no continuously mined fuel; its critical-mineral demand is one-time and comparatively modest per unit energy.

Critical minerals — lithium, rare earths, cobalt, and others — are a growing concern for all clean-energy technologies, since they concentrate supply in a few regions and require mining with its own footprint. Fusion's relationship to critical minerals is distinctive: it uses some in construction, but it does not consume a continuously mined fuel the way fossil and, to a lesser extent, fission plants do.

One-time build versus continuous fuel

A fossil plant mines and burns fuel every day it runs. A fusion plant uses its critical minerals largely once, in construction — lithium for the breeding blanket, rare-earth elements within superconductor and magnet systems, and specialty alloys. After that, its fuel is deuterium from water plus bred fuel. Per unit of firm clean energy delivered over a plant's life, that one-time mineral demand is comparatively modest.

Honest caveats

Lithium supply is genuinely constrained and is shared with the battery sector, and superconductor manufacturing scale is a real limit — Kronos treats both as active program concerns, not solved problems. The defensible claim is about character, not magnitude: fusion's critical-mineral demand is concentrated in the build rather than the fuel, and its energy output per unit of mineral over a plant lifetime is high because it burns effectively unlimited deuterium.

• Critical-mineral concerns apply to all clean technologies.
• Fusion uses lithium, rare earths, and specialty alloys mainly in construction.
• Its fuel is deuterium from water — not a continuously mined mineral.
• Lithium and superconductor supply are real, openly acknowledged constraints.

Design-and-simulation framing. The Kronos machines are today design and simulation studies: the breeder (Hyperion) and the burner (Aegis / MetroVolt). No hardware net-gain has been demonstrated. Breeder construction is planned to begin Q2 2027, with first-of-a-kind (FOAK) first tritium targeted around 2030. Comparisons on this page are qualitative and use only public, defensible figures; nothing here is a performance guarantee.

Fusion's critical-mineral profile is favorable in character — build-time, not fuel — and stated with its genuine lithium and superconductor constraints in view.