MetroVolt's first-of-a-kind direct-cost basis is $3,150M, assembled as a line-item bill of materials — magnets to shield to conversion train to buildings — rather than scaled from someone else's reactor study.
The BOM prices the frozen design point: the ~31,300 km REBCO conductor order and winding, the WC/W₂B₅ shield stack at its computed ≈1.20 m minimum, the vessel in its qualification-target alloy class, the multi-modal DEC train, cryoplant, heating and current-drive systems, and balance of plant — each line carrying its own basis and contingency posture in the finance model.
Dividing through the ceiling-basis net output yields the capex-per-kilowatt ladder that seeds the model — and the honest companion figure is stated with it: at the 486 MWe operating point the same capital prices ≈1.8–2.5× higher per kilowatt until the ceiling is earned, which is why the gates are commercial gates. This ladder seeds the published ladder scenarios; the model and the physics deposit quote each other, so the engineering and the economics cannot silently diverge.
A bottom-up BOM is auditable: a supplier can quote against a line, a diligence engineer can challenge one, and cost learning can be tracked line-by-line as the fleet builds. The $3.15B figure is not small — it is simply real, and every rung of the cost ladder stands on it.
| FOAK direct-cost basis | $3,150M (line-item BOM) |
| Largest lines | magnets · shield · DEC train |
| Conductor order | ≈31,300 km REBCO |
| Feeds | capex/kWe scenarios → LCOE ladder |
| Consistency | finance model reconciled to the physics deposit |