KRONOS·FUSION
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Comparison

Copper vs Superconducting Magnets

Copper magnets waste enormous power as heat and can't sustain high fields continuously. Superconducting magnets carry current losslessly — essential for a power reactor.

Copper
Resistive — dissipates large power as heat
Superconducting
Zero resistance — lossless
For a power plant
Superconducting is essential
Kronos
HTS / REBCO

Early and experimental tokamaks often used resistive copper magnets, which work but at a steep price: copper has electrical resistance, so sustaining a strong field means continuously dissipating enormous amounts of power as heat — impractical for a machine meant to produce net energy.

PropertySuperconducting / Copper
ResistanceZero (lossless) / significant (dissipates power)
Steady high fieldSustained efficiently / very costly, often pulsed
Power-plant fitEssential / impractical

A commercial reactor needs magnets that hold a strong field continuously without eating the plant's output — which means superconductors. Kronos uses HTS (REBCO), whose lossless high field is what makes the whole engineering-gain equation work. See HTS vs LTS magnets for the superconductor comparison.