Onagawa
Reactor Data
Reactor Units
Every power reactor at this site as listed in the IAEA Power Reactor Information System (PRIS): reactor type and model, net electrical capacity, grid connection and commercial operation dates, and current status.
3 units: 1 operational, 1 suspended operation, 1 permanent shutdown.
Net capacity in service: 1,592 MWe.
| Unit | Type | Model | Net MWe | Construction | Grid | Commercial Op | Shutdown | Status |
|---|---|---|---|---|---|---|---|---|
| Onagawa 1 | BWR | BWR-4 | 498 | 1980-07-08 | 1983-11-18 | 1984-06-01 | 2018-12-21 | Permanent Shutdown |
| Onagawa 2 | BWR | BWR-5 | 796 | 1991-04-12 | 1994-12-23 | 1995-07-28 | Operational | |
| Onagawa 3 | BWR | BWR-5 | 796 | 1998-01-23 | 2001-05-30 | 2002-01-30 | Suspended Operation |
Capacity, milestones and suppliers
| Unit | Design MWe | Gross MWe | Thermal MWt | First Criticality | Reactor Supplier | Turbine Supplier | Notes |
|---|---|---|---|---|---|---|---|
| Onagawa 1 | 496 | 524 | 1,593 | 1983-10-18 | TOSHIBA CORPORATION | TOSHIBA CORPORATION | Decommissioning from 2020-07-28 |
| Onagawa 2 | 796 | 825 | 2,436 | 1994-11-02 | TOSHIBA CORPORATION | TOSHIBA CORPORATION | Suspended 2011-03-11; Restarted 2024-11-15 |
| Onagawa 3 | 796 | 825 | 2,436 | 2001-04-26 | TOSHIBA CORPORATION | HITACHI, LTD. | Suspended 2011-03-11 |
Lifetime performance, through 2025
| Unit | Electricity Supplied | Load Factor | Energy Availability | Operating Factor |
|---|---|---|---|---|
| Onagawa 1 | 81.8 TWh | 52.1% | 51.9% | 52.5% |
| Onagawa 2 | 88.8 TWh | 74.5% | 74.1% | 74.4% |
| Onagawa 3 | 43.7 TWh | 68.8% | 66.8% | 67.3% |
Operator: Tohoku Electric Power Co., Inc
Owner: Tohoku Electric Power Co., Inc
Source: IAEA Power Reactor Information System (PRIS), as of 2026-11-02.
Working Here
Per Diem Rates FY 2026
Per diem covers lodging and meals & incidental expenses (M&IE) for government and contractor travel near this facility. Rates are from the U.S. State Department foreign per diem tables for FY 2026.
$208
Lodging/Night
$107
M&IE/Day
$315
Total/Day
Japan: rate for locations the State Department does not list separately
U.S. Department of State foreign per diem, for U.S. government and contractor travel.
Photos
Photos of this facility from the NukeWorker photo gallery. Click the header or any photo to browse the full album.
Facility Map
Interactive satellite map showing the facility's geographic location. Marker color indicates current status: green for online, red for offline, orange for reduced power. Click the header to open in Google Maps satellite view.
38.4011, 141.5
Location & Contact
Physical address, phone number, and website for this facility. Use the directions link to get driving directions via Google Maps.
Plant Facts
About This Site
Written by NukeWorker from public records: facts that do not change. Operator, status and capacity come from the live data elsewhere on this page. Sources: Wikipedia: Onagawa Nuclear Power Plant.
Onagawa Nuclear Power Plant is in the town of Onagawa and the city of Ishinomaki in Miyagi Prefecture, Japan.
Read more
Toshiba built all three boiling water reactors. Construction of Unit 1 began on 8 July 1980, Unit 2 on 12 April 1991 and Unit 3 on 23 January 1998, and the units were connected to the grid on 18 November 1983, 23 December 1994 and 30 May 2001. The plant was the one closest to the epicenter of the 11 March 2011 Tohoku earthquake. All three units shut down automatically without reactor damage, and a fire in a turbine building was put out soon after. Unit 1 was permanently shut down on 21 December 2018.