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Comparison
Direct Conversion vs the Steam Cycle
Direct energy conversion turns charged particles straight into electricity; a steam cycle boils water for a turbine. DEC skips the Carnot limit and shrinks the plant.
- DEC
- Charged particles → electricity directly; DC-native
- Steam cycle
- Heat → steam → turbine; Carnot-limited
- Efficiency ceiling
- DEC bypasses Carnot; steam ~33–45%
- Plant
- DEC thermally light; steam needs turbine hall
How a fusion plant converts reactions to electricity shapes the entire machine. Most concepts use a steam cycle — neutrons heat a blanket, the heat boils water, steam spins a turbine — the same back end as a coal or fission plant, bounded by the Carnot limit. Kronos uses direct energy conversion, capturing charged-particle energy straight as electricity.
| Dimension | Direct conversion / Steam cycle |
|---|---|
| Efficiency ceiling | No Carnot limit / capped ~33–45% |
| Output | DC-native / AC via turbine-generator |
| Balance of plant | Thermally light, compact / large turbine hall + cooling |
| Works on | Charged particles (needs low-neutron fuel) / heat (any fuel) |
The catch is that DEC only works on charged particles — which is exactly why Kronos pairs it with a low-neutron fuel. Fuel and conversion are one decision.