Helium-3 from Tritium Decay

Helium-3 is the daughter of tritium; breeding tritium today seeds a helium-3 supply for years afterward.

One isotope becomes another

Tritium beta-decays into helium-3 with a half-life of about 12.3 years. This is not a loss to be minimized so much as a transformation to be captured: the helium-3 that accumulates as tritium decays is exactly the gas that neutron detectors need. Historically it has been the principal helium-3 source.

Two routes, one machine

A fusion breeder therefore contributes helium-3 by two paths. First, it is designed to co-produce helium-3 directly, near 1.97 kg/yr in the design study. Second, the tritium it produces, in the 4 kg/yr class, will itself decay over the following years, yielding more helium-3. The two routes reinforce each other over time.

• Direct co-production in the breeder's neutron economy
• Indirect accrual from decay of bred tritium
• A durable, compounding supply pathway

Public and honest

These are design-study figures for a machine under a Q2 2027 construction start. Kronos presents helium-3 as a strategic supply contribution at a public level; it makes no operational or allocation claims.

A compounding supply

The two routes reinforce each other over time. Direct co-production supplies helium-3 while the breeder runs, and the tritium it produces continues yielding helium-3 for years afterward as it decays. A program that breeds tritium today is therefore seeding a helium-3 stream that keeps accruing well into the future. This compounding character makes fusion breeding a durable answer to a shortage that byproduct-only supply could never keep ahead of.

This is a public overview only. It contains no classified information, no operational detail, and no weapons-design content.