Fusion Gain (Q) and Engineering Gain
Q is the number everyone quotes — but it is not the number that keeps the lights on. Kronos is careful to distinguish scientific gain from the plant-level gain that matters commercially.
- Breeder Q
- 3.424
- Breeder P_fus
- 88.7 MW
- Breeder P_aux
- 25.9 MW
- Burner Q_E
- 1.31
- DEC efficiency
- 0.70
Fusion gain Q is the ratio of fusion power produced to external heating power supplied. Q = 1 is scientific break-even; Q → ∞ is ignition. The HYPERION breeder is designed for Q = 3.424 — its 88.7 MW of fusion power against 25.9 MW of auxiliary heating.
Scientific vs engineering gain
Q measures the plasma. The plant-level engineering gain counts net electricity delivered to the grid against every watt the facility consumes — magnets, cryogenics, heating, pumps, controls. A machine can have an impressive Q and still not be a net electricity producer. Kronos reports the plant-level ledger separately for each product housing rather than letting a high plasma Q stand in for commercial viability.
The burner's direct advantage
The D–³He burner is quoted at an engineering gain QE = 1.31 because it converts charged-particle energy straight to electricity via direct energy conversion at about 0.70 efficiency, skipping the thermal cycle's losses.