KRONOS·FUSION
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Question

How is fusion different from nuclear fission?

Fusion joins light nuclei; fission splits heavy ones. Fusion has no chain reaction or spent fuel; Hyperion’s activated structures remain disposable Class C low-level waste under the qualified alloy specification.

Fusion and fission are often lumped together as "nuclear," but they are near-opposites. The differences that matter for a power plant are safety and waste: fusion cannot run away, and it leaves nothing like the long-lived spent fuel of fission.

Kronos MetroVolt sharpens both advantages by being low-neutron — minimizing even the modest activation that fusion neutrons cause.

Questions & answers

What's the basic difference?
Fission splits heavy atoms (like uranium) into lighter ones; fusion joins light atoms (like deuterium and helium-3) into heavier ones. Both release energy, but the physics — and the safety and waste consequences — are completely different.
Can a fusion plant melt down like a fission reactor?
No. Fission relies on a self-sustaining chain reaction that must be actively controlled; fusion has no chain reaction. A fusion plasma holds only seconds of fuel, and any interruption to heating, fuel, or confinement simply stops it. There is no meltdown pathway.
What about the waste?
Fission produces long-lived radioactive spent fuel. Fusion produces no spent fuel, but neutrons activate structural materials. For Hyperion, the qualified Cr-Ti-V-W alloy and impurity specification keep every component at or below Class C for disposal; a small long-lived fraction remains below the Class-C boundary. A low-neutron burner produces less activation.

Activated structures classify at or below Class C low-level waste — disposable, with no greater-than-Class-C material and no deep-geologic repository — when built to the qualified low-activation copper-, tantalum-, rhenium-, and molybdenum-free Cr-Ti-V-W alloy and its impurity specification (niobium <= 5 ppm, controlled nitrogen). A small long-lived fraction remains, well below the Class-C boundary. This is disposable low-level waste, not free-release.

This reflects our latest activation analysis (2026).

Related

Is fusion power safe? →Can a fusion reactor explode or melt down? →Does fusion produce radioactive waste? →Fusion Waste & Decommissioning →