Mihama
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, 2 permanent shutdown.
Net capacity in service: 780 MWe.
| Unit | Type | Model | Net MWe | Construction | Grid | Commercial Op | Shutdown | Status |
|---|---|---|---|---|---|---|---|---|
| Mihama 1 | PWR | WH 2LP | 320 | 1967-02-01 | 1970-08-08 | 1970-11-28 | 2015-04-27 | Permanent Shutdown |
| Mihama 2 | PWR | M (2-loop) | 470 | 1968-05-29 | 1972-04-21 | 1972-07-25 | 2015-04-27 | Permanent Shutdown |
| Mihama 3 | PWR | M (3-loop) | 780 | 1972-08-07 | 1976-02-19 | 1976-12-01 | Operational |
Capacity, milestones and suppliers
| Unit | Design MWe | Gross MWe | Thermal MWt | First Criticality | Reactor Supplier | Turbine Supplier | Notes |
|---|---|---|---|---|---|---|---|
| Mihama 1 | 320 | 340 | 1,031 | 1970-07-29 | WESTINGHOUSE ELECTRIC CORPORATION | MITSUBISHI HEAVY INDUSTRIES, LTD. | |
| Mihama 2 | 470 | 500 | 1,456 | 1972-04-10 | MITSUBISHI HEAVY INDUSTRIES, LTD. | MITSUBISHI HEAVY INDUSTRIES, LTD. | |
| Mihama 3 | 780 | 826 | 2,440 | 1976-01-28 | MITSUBISHI HEAVY INDUSTRIES, LTD. | MITSUBISHI HEAVY INDUSTRIES, LTD. |
Lifetime performance, through 2025
| Unit | Electricity Supplied | Load Factor | Energy Availability | Operating Factor |
|---|---|---|---|---|
| Mihama 1 | 60.1 TWh | 48.3% | 47.5% | 50.2% |
| Mihama 2 | 101.6 TWh | 57.7% | 57.6% | 58.6% |
| Mihama 3 | 190.7 TWh | 56.8% | 56.0% | 56.7% |
Operator: Kansai Electric Power Co.
Owner: Kansai Electric Power Co.
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.
35.7024, 135.963
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: Mihama Nuclear Power Plant.
Mihama Nuclear Power Plant is in the town of Mihama, Fukui Prefecture, Japan, on Nyunoura Bay on the Sea of Japan.
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Construction of Unit 1 began on 1 February 1967, Unit 2 on 29 May 1968 and Unit 3 on 7 August 1972. All three are pressurized water reactors, and Unit 3 is a Westinghouse-type three-loop design. Unit 1 was connected to the grid on 8 August 1970, Unit 2 on 21 April 1972 and Unit 3 on 19 February 1976. On 9 August 2004 a steam pipe burst in the Unit 3 turbine building, killing five workers and injuring six. Units 1 and 2 were permanently shut down on 27 April 2015.