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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, cannot melt down, and leaves no long-lived waste.
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 that stays hazardous for thousands of years. Fusion produces no spent fuel — only structural materials made mildly radioactive by neutrons, which decay to recyclable levels in about a century. A low-neutron design like Kronos produces even less.