goingcritical:holtec-smr-300-palisadesUnited States · SMR

Palisades Pioneer 1 & 2 (SMR-300)

Status: Announced target criticality 2031 (confidence: low) ? Reactor status full glossary → Announced Publicly announced — a site and design are proposed, but construction has not begun. Site preparation Early site and civil works are under way; the first safety-related ("nuclear") concrete has not yet been poured. Under construction Formal construction has begun, marked by the first nuclear concrete. Fuel loaded Nuclear fuel has been loaded into the core. The reactor is fuelled but has not yet gone critical. Critical Has reached first criticality — a self-sustaining chain reaction, usually at low power — but is not yet connected to the grid. Grid connected Synchronised to the electrical grid and exporting power for the first time, but still in commissioning and power-ascension testing — not yet in commercial service. Operating In commercial operation — the operator has formally declared the unit in regular commercial service. Shut down Permanently shut down and no longer generating; may be defuelled, undergoing decommissioning, or preserved in place. Canceled Abandoned before completion.

Developer: Holtec International (with Hyundai E&C)

Site: Palisades site, Covert Township, Michigan

New YorkChicagoTorontoProvidenceVirginia BeachColumbusKansas City

Holtec targets bringing the two SMR-300 units online in the early 2030s (2031 per July 2026 reporting); CPA Part 1 with limited work authorization docketed by NRC Feb 27, 2026, with Part 2 planned by 2027

Details

Design	Holtec SMR-300 PWR (twin units; capacity shown is per unit)
Electrical output	300 MWe

Milestone history

1. Announced December 2025
2. Construction start —
3. Fuel load —
4. First criticality target 2031
5. Grid connection —
6. Commercial operation —