Kashiwazaki-Kariwa 6 is a 1,315 MWe (net) TEPCO ABWR at the world's largest nuclear plant by capacity. It restarted in February 2026 after almost 14 years offline and resumed commercial operation on 16 April 2026, TEPCO's first reactor back since Fukushima.
Background: Palisades fuel loading: Holtec restart timeline and what comes next · NRC reactor licensing process, explained
Current state
| Status | Restarted |
| Country | Japan |
| Location | Kashiwazaki and Kariwa, Niigata Prefecture |
| Plant | Kashiwazaki-Kariwa |
| Unit | 6 |
| Operator | Tokyo Electric Power Company (TEPCO) |
| Reactor type | BWR |
| Net capacity (MWe) | 1,315 |
| Restart type | Post-Fukushima restart |
| Shut down | 2012-03-26 |
| Restarted | 2026-02-09 |
| Years offline | 13.9 |
| Regulator | NRA approval 2017-12-27; specialised (anti-terrorism) safety facility deadline September 2029 |
| Local consent | Niigata governor consented 2025-11-21; prefectural assembly backed the decision 2025-12-22 |
Notes
ABWR recorded as BWR. Net capacity from WNA (1,356 MWe gross). Power generation resumed 2026-02-16; restart was suspended mid-March to investigate generating equipment, resumed 2026-03-22 (JAIF). TEPCO pledged ~JPY100bn over ~10 years to Niigata (WNN).
Timeline
- 2012-03-26 — Kashiwazaki-Kariwa 6 went offline for a periodic inspection. (source)
- 2017-12-27 — The NRA approved units 6 and 7. (source)
- 2025-06-21 — TEPCO completed fuel loading. (source)
- 2025-11-21 — Niigata Governor Hideyo Hanazumi consented to restarting units 6 and 7. (source)
- 2025-12-22 — The Niigata Prefectural Assembly backed the governor, completing local consent. (source)
- 2026-01-21 — TEPCO began a restart that was suspended the next day by a control-rod alarm. (source)
- 2026-02-09 — TEPCO restarted the reactor, reaching criticality the same afternoon. (source)
- 2026-04-16 — The unit resumed commercial operation. (source)
The timeline is append-only: corrections are added as new entries. Stated targets appear in the current-state table, never as milestones.
Related units
- Genkai Unit 3 Restarted · Japan
- Genkai Unit 4 Restarted · Japan
- Hamaoka Unit 3 Cancelled · Japan
- Hamaoka Unit 4 Cancelled · Japan
- Higashidori Unit 1 (Tohoku Electric) Under review · Japan
- Ikata Unit 3 Restarted · Japan
- Kashiwazaki-Kariwa Unit 7 Approved · Japan
- Mihama Unit 3 Restarted · Japan
See all 45 units in the Nuclear Plant Restarts Tracker →
Sources
- Current Status of Nuclear Power Plants in Japan as of August 7, 2026 — Japan Atomic Industrial Forum (JAIF) (primary), checked 2026-10-11
- Nuclear Power in Japan — World Nuclear Association, checked 2026-10-11
- Niigata governor consents to restart of Kashiwazaki-Kariwa reactors — World Nuclear News, checked 2026-10-11
- Restart of Kashiwazaki-Kariwa reactors approved by regional assembly — World Nuclear News, checked 2026-10-11
- Tepco restarts Kashiwazaki-Kariwa unit 6 — World Nuclear News, checked 2026-10-11
- Kashiwazaki-Kariwa 6 resumes commercial operation — World Nuclear News, checked 2026-10-11
- Nuclear reactor restart in Japan will likely displace natural gas electricity generation — U.S. Energy Information Administration (primary), checked 2026-10-11
- Tepco resumes commercial operations at Niigata plant for first time in 14 years — The Japan Times, checked 2026-10-11