The 30-second answer
How much nuclear power is actually under binding contract in the data-center and public-power deal book?
14.2 GW is binding (deal tiers 1–3). 95% of it comes from reactors that already exist.
a Binding · existing, restarted or uprated
13.5 GW
9,617 MW from operating plants (Tier 1) + 3,864 MW from restarts and uprates (Tier 2).
b Binding · new reactors
0.67 GW
3 units of new build with a binding buyer: 670 MW.
c Non-binding pipeline · tiers 5–8
43.8 GW
3.1× the binding total. Largest single line: Oklo–Switch, 12 GW, non-binding by its own terms.
a · existing/restart/uprateb · new reactorsTier 4 equity (320 MW, Cascade Phase 1)c · non-binding, tiers 5–8
What the number does and doesn’t say
- The three binding new reactors:
- Hermes 2 — 50 MWe; PPA Aug 2025; groundbreaking Apr 2026; target 2030. A
- Long Mott Generating Station — 4 × Xe-100 ≈ 320 MWe (+ process heat); NRC final SE targeted Nov 2026. A
- Darlington BWRX-300 Unit 1 — ~300 MWe (Unit 1 of 4); Approved May 8, 2025; complete end-2029; grid 2030. B
- Not yet cut by delivery date. Several binding rows land in 2030 or later (the Meta and Amazon uprate shares, part of Google’s PJM uprates, Hermes 2, Darlington Unit 1). A strict before-2030 cut comes with the Control Room.
- MWe as claimed by the parties, not metered delivery. Fusion comparators and rows with no stated MW are left out of the totals; nested sub-deals are counted once.
- Seed figures from the Deal Tracker as of Oct 23, 2026, checked Oct 26, 2026. Full rules on the Method page; the underlying data are in meta.json and deals.json.
Multiplication factor bands
k < 1
Subcritical
Announced, MOU’d, pre-application or unfunded. Needs outside neutrons to keep going.
44.1 GW · 23 deals
k = 1
Critical
Self-sustaining evidence: binding offtake, docketed review or permit, financing closed, not yet producing.
3.7 GW · 9 deals
k > 1
Supercritical
Adding energy: operating plants under contract, or fuel in the core.
10.4 GW · 8 deals
The limiting factor sets the band. A deal view reads the offtake, so Kemmerer, under construction with no verified buyer, sits at k < 1. How bands are assigned.
Pipeline by deal tier
Claimed MWe, fission only · 42 deals · as of Oct 23, 2026
| Tier | What binds the buyer | Deals | MW counted | Scale |
|---|---|---|---|---|
| 1 | Binding PPA, operating plant | 7 | 9,617 MW | |
| 2 | Restart/uprate with offtaker | 7 | 3,864 MW | |
| 3 | Binding offtake, new reactor | 5 | 670 MW | |
| 4 | Offtaker equity | 1 | 320 MW | |
| 5 | Development/site with milestones | 7 | 7,445 MW | |
| 6 | Framework / MOU / GW target | 9 | 27,840 MW | |
| 7 | RFP / LOI / exploring | 6 | 8,498 MW | |
| 8 | 'Nuclear-powered' campus, no vendor/license/fuel None classed yet; Fermi America (Tier 7) is closest. | 0 | — |
Tier is set by the strongest evidence that binds the buyer, not by the headline. A grade-A docket can sit on a Tier 7 deal (Fermi America), and a grade-C press release can describe a Tier 1 PPA.
From the Promise Ledger
Log excerpt · 45 promises tracked: 2 delivered, 13 slipped, 1 dropped, 1 cancelled, 28 pending
| Promisor | Promise | Target | Status | Slippage / outcome | Grade | Source |
|---|---|---|---|---|---|---|
| TerraPower | Natrium Kemmerer Unit 1 operating (345 MWe) | 2028 → 2031 (grid) | slipped | ~36 months; HALEU delay disclosed Dec 2022 | A | FR 2026-05067 |
| Holtec | Return Palisades (805 MW) to service | Q4 2025 → no new grid date | slipped | ≥10 months; fuel load began Aug 30, 2026 | A | FR 2026-21594 |
| UAMPS / NuScale | Carbon Free Power Project, 462 MWe | Terminated Nov 8, 2023 | cancelled | Target price 1.53× ($58 → $89/MWh) | A | NuScale 8-K |
| DOE Reactor Pilot Program | At least 3 test reactors critical by Jul 4, 2026 | Jul 4, 2026 | delivered | Met: 4 criticalities, all zero-power; 7 other selectees missed the date | B | DOE, 4th criticality |
| Constellation / Microsoft | Restart Crane (TMI-1), 835 MW | 2028 → 2027 | pending | −12 months (ahead of plan) | A | FR 2026-19603 |
Rows are never deleted. When a date moves, the new outcome is appended and the original stays. Credit where due: the DOE pilot goal was met, and Crane is running ahead of plan. More rows from the ledger.