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Comparison
D–³He vs D–D
D–D is the reaction that breeds Kronos's helium-3; D–³He is the low-neutron reaction that produces most of the power. The catalyzed cycle uses both together.
- D–D
- Deuterium + deuterium; breeds ³He and tritium
- D–³He
- Deuterium + helium-3; low-neutron, high-value
- Together
- Catalyzed cycle: D–D feeds D–³He
- Neutrons
- D–D is the residual neutron source
These two reactions aren't alternatives in the Kronos design — they work together in a catalyzed cycle. D–D fusion (deuterium with itself) breeds the fuel; D–³He fusion (deuterium with helium-3) produces the clean, directly-convertible power.
| Property | D–³He / D–D |
|---|---|
| Products | Proton + alpha (charged) / ³He + neutron, or tritium + proton |
| Role at Kronos | Primary power reaction / breeds ³He and tritium in situ |
| Neutrons | Aneutronic (primary) / one branch emits a neutron |
The elegance is that D–D reactions running alongside D–³He breed the helium-3 the plant needs, so it isn't dependent on scarce external supply. The price is that the D–D neutron branch is what makes the plant low-neutron rather than neutron-free — an honest, quantified trade.