Deuterium Storage
Deuterium is stored as compressed gas, cryogenic liquid, or metal hydride; its abundance makes storage a matter of convenience rather than scarcity.
Storing the abundant fuel
Deuterium storage is comparatively relaxed. Unlike helium-3, deuterium is cheap to replace and effectively unlimited, so storage is chosen for operational convenience rather than to guard against loss. Three forms are common: compressed gas in cylinders, cryogenic liquid for high density, and metal hydride beds that absorb deuterium and release it on mild heating. Hydride storage is attractive because it holds a lot of fuel at low pressure and improves safety.
Hydride beds
Metal hydride storage deserves note because it is the deuterium option with no helium-3 equivalent. Certain metals absorb hydrogen isotopes into their crystal lattice, storing deuterium as a solid-bound gas at near-ambient pressure and releasing it when gently warmed. This gives compact, low-pressure, controllable storage that pairs well with the metered demands of fuel conditioning. Helium-3, being a noble gas, cannot be stored this way and must always be kept as gas.
- Deuterium stored as compressed gas, cryogenic liquid, or hydride
- Storage chosen for convenience, not loss prevention
- Hydride beds hold much fuel at low pressure, safely
- No hydride option exists for noble-gas helium-3
The contrast with helium-3 storage underlines the asymmetry of the fuel supply: one fuel is stored casually and the other guarded closely, reflecting which is abundant and which is bred.