goingcritical:fukushima-daiichi-4Japan · Power reactor
Fukushima Daiichi 4
Status: Shut down reached first criticality January 28, 1978 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. 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.
Site: Okuma, Fukushima
Defueled and offline for maintenance when the March 2011 disaster struck, yet its reactor building was still wrecked by a hydrogen explosion on 2011-03-15, with the spent-fuel pool a major crisis focus. Permanently shut down 2011-05-19.
Details
| Design | GE BWR-4 (Mark I containment) |
| Electrical output | 760 MWe |
Milestone history
- Announced —
- Construction start February 12, 1973
- Fuel load —
- First criticality January 28, 1978
- Grid connection February 24, 1978
- Commercial operation October 12, 1978