Honest Limits & Open Gates

A plain summary of what fusion cannot yet claim: the machines are unbuilt, and the burner carries four specific, unsoftened engineering gates.

Every comparison in this section is bounded by one fact stated first, not last: the Kronos machines are design-and-simulation studies, not operating plants. The breeder (Hyperion) and burner (Aegis / MetroVolt) have not demonstrated hardware net gain. Breeder construction is planned for Q2 2027, with first-of-a-kind first tritium targeted around 2030. Nothing here is a performance guarantee.

The four burner gates

The burner carries four specific gates that Kronos states plainly and never softens or converts into economics. They are physics-and-engineering findings from simulation, and closing them is future work.

What fusion can and cannot claim

Defensible today: no CO₂ or combustion pollutants at generation; low lifecycle carbon; compact footprint; short-lived, recyclable activated waste; no meltdown or chain-reaction pathway; abundant deuterium fuel. Not claimable today: demonstrated net gain, proven availability, a terrestrial helium-3 supply for the burner, or any economic figure. The breeder's tritium breeding ratio is a design lever (1.1/1.5/1.8), not a settled result.

• The machines are unbuilt design-and-simulation studies; no net-gain claim.
• Burner: plug-coil overstress ~3-3.9x — infeasible as specified.
• Burner: operating regime 166-830x beyond any device; helium-3 ~400x short.
• Burner: availability ~0.86-0.995 vs Tier III 0.99982 — not a sole Tier III source.

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.

Stating limits plainly is the point of this section: fusion's real advantages are strong enough that they need no exaggeration, and the open gates are shown in full.