Onagawa nuclear power plant 1
Retired Japan
Gross capacity
524MW
Onagawa nuclear power plant 1 is a boiling water reactor unit at Onagawa nuclear power plant in Japan rated at 524 MW gross. It is retired. Commercial operation began 1 Jun 1984.
Specification
| Reactor type | Boiling water reactor (BWR) |
|---|---|
| Model | BWR-4 |
| Size class | Large |
| Coolant | Light water |
| Moderator | Light water |
| Gross capacity | 524MW |
| Net capacity (reference) | 498MW |
| Net capacity (design) | 498MW |
| Thermal output | 1,593MWt |
| Typical enrichment | 3–5% U-235 |
Ownership & location
| Site | Onagawa nuclear power plant |
|---|---|
| Unit | 1 |
| Country | Japan |
| Owner | Tohoku Electric Power Co Inc100% |
| Operator | Tohoku Electric Power |
| Coordinates | 38.3987, 141.5003 |
Fuel chain for this unit
Fuel form
Uranium dioxide pellets in zirconium-alloy cladding
Enrichment
3–5% U-235
Who makes this assembly
- Framatome BWR fuel assemblies
- Global Nuclear Fuel BWR fuel assemblies
- Westinghouse Electric Company BWR fuel assemblies
Upstream
Enriched fuel means this unit sits downstream of five conversion plants and four enrichment operators holding 88% of world capacity between the top three.
Fabricator capability is recorded against reactor type and model line, not against named units —
utilities do not publish fuel contracts. See the fuel chain.
Timeline
- 8 Jul 1980Construction start
- 18 Oct 1983First criticality
- 18 Nov 1983Grid connection
- 1 Jun 1984Commercial operation
- 21 Dec 2018Permanent shutdown
Other units at Onagawa nuclear power plant
| Unit | Status | Gross MW |
|---|---|---|
| Onagawa nuclear power plant 2 | 825 | |
| Onagawa nuclear power plant 3 | Mothballed | 825 |
Other BWR-4 units
8 units worldwide share this model designation.
| Unit | Country | Status | Gross MW |
|---|---|---|---|
| Fukushima Daiichi nuclear power plant 2 | Japan | Retired | 784 |
| Fukushima Daiichi nuclear power plant 3 | Japan | Retired | 784 |
| Fukushima Daiichi nuclear power plant 4 | Japan | Retired | 784 |
| Fukushima Daiichi nuclear power plant 5 | Japan | Retired | 784 |
| Hamaoka nuclear power plant 1 | Japan | Retired | 540 |
| Hamaoka nuclear power plant 2 | Japan | Retired | 840 |
| Muehleberg nuclear power plant 1 | Switzerland | Retired | 390 |
Sources
- Global Nuclear Power Tracker, Global Energy Monitor, August 2026 release — CC BY 4.0 · retrieved 2026-09-06 · this unit last researched by GEM on 2024-05-16
- GEM.wiki entry (further reading) — CC BY-SA 4.0 — linked, not quoted