Tomari nuclear power plant
Tomari nuclear power plant is a nuclear site in Japan with 3 units on record. None is currently operating.
Units
| Unit | Status | Type | Model | Gross MW | Online |
|---|---|---|---|---|---|
| Unit 1 | Mothballed | PWR | M (2-loop) | 579 | 1989 |
| Unit 2 | Mothballed | PWR | M (2-loop) | 579 | 1991 |
| Unit 3 | Mothballed | PWR | M (3-loop) | 912 | 2009 |
Unit by unit
Each unit's rating, type and milestone dates as recorded by the Global Nuclear Power Tracker, with any correction we made to it. A dash or "not disclosed" means the source does not give the value.
Tomari nuclear power plant 1 Mothballed
| Reactor type | Pressurised water reactor (PWR) |
|---|---|
| Model | Mitsubishi 2-loop |
| Size class | Large |
| Gross capacity | 579MW |
| Net capacity | 550MW |
| Thermal output | 1,650MWt |
| Enrichment | 3–5% U-235 |
| NSSS vendor | Mitsubishi Heavy Industries |
| Owner | Hokkaido Electric Power Co Inc100% |
| Operator | Hokkaido Electric Power |
| Construction start | 18 Apr 1985 |
|---|---|
| First criticality | 16 Nov 1988 |
| Grid connection | 6 Dec 1988 |
| Commercial operation | 22 Jun 1989 |
Tomari nuclear power plant 2 Mothballed
| Reactor type | Pressurised water reactor (PWR) |
|---|---|
| Model | Mitsubishi 2-loop |
| Size class | Large |
| Gross capacity | 579MW |
| Net capacity | 550MW |
| Thermal output | 1,650MWt |
| Enrichment | 3–5% U-235 |
| NSSS vendor | Mitsubishi Heavy Industries |
| Owner | Hokkaido Electric Power Co Inc100% |
| Operator | Hokkaido Electric Power |
| Construction start | 13 Jun 1985 |
|---|---|
| First criticality | 25 Jul 1990 |
| Grid connection | 27 Aug 1990 |
| Commercial operation | 12 Apr 1991 |
Tomari nuclear power plant 3 Mothballed
GNPT records the unit as under construction, with a commercial operation date in the future. The Japan Atomic Industrial Forum's table of the status of Japan's nuclear power plants, as of 7 August 2026, lists Tomari-3 (PWR, 912 MWe) among the operable units, commercial operation 2009, in outage since 2012.05.05. Only Ohma, Higashidori-1 and Shimane-3 are in its under-construction table. The unit is complete and idle, like its sister units already recorded as mothballed, so it is not under construction. The commercial operation year is the JAIF's; the exact day is not given there, so only the year is recorded.
status:
construction → mothballed
· Japan Atomic Industrial Forum, Current Status of Nuclear Power Plants in Japan (as of 7 August 2026)
· verified 2026-10-22
GNPT records the unit as under construction, with a commercial operation date in the future. The Japan Atomic Industrial Forum's table of the status of Japan's nuclear power plants, as of 7 August 2026, lists Tomari-3 (PWR, 912 MWe) among the operable units, commercial operation 2009, in outage since 2012.05.05. Only Ohma, Higashidori-1 and Shimane-3 are in its under-construction table. The unit is complete and idle, like its sister units already recorded as mothballed, so it is not under construction. The commercial operation year is the JAIF's; the exact day is not given there, so only the year is recorded.
commercial_operation:
2027-01-01 → 2009
· Japan Atomic Industrial Forum, Current Status of Nuclear Power Plants in Japan (as of 7 August 2026)
· verified 2026-10-22
GNPT records the unit as under construction, with a commercial operation date in the future. The Japan Atomic Industrial Forum's table of the status of Japan's nuclear power plants, as of 7 August 2026, lists Tomari-3 (PWR, 912 MWe) among the operable units, commercial operation 2009, in outage since 2012.05.05. Only Ohma, Higashidori-1 and Shimane-3 are in its under-construction table. The unit is complete and idle, like its sister units already recorded as mothballed, so it is not under construction. The commercial operation year is the JAIF's; the exact day is not given there, so only the year is recorded.
start_year:
2027 → 2009
· Japan Atomic Industrial Forum, Current Status of Nuclear Power Plants in Japan (as of 7 August 2026)
· verified 2026-10-22
| Reactor type | Pressurised water reactor (PWR) |
|---|---|
| Model | Mitsubishi 3-loop |
| Size class | Large |
| Gross capacity | 912MW |
| Net capacity | 866MW |
| Thermal output | 2,660MWt |
| Enrichment | 3–5% U-235 |
| NSSS vendor | Mitsubishi Heavy Industries |
| Owner | Hokkaido Electric Power Co Inc100% |
| Operator | Hokkaido Electric Power |
| Construction start | 18 Nov 2004 |
|---|---|
| First criticality | 3 Mar 2009 |
| Grid connection | 20 Mar 2009 |
| Commercial operation | 2009 |
Tomari nuclear power plant in context
The nearest other tracked nuclear sites are Ohma nuclear power plant (173 km).
Nearest tracked nuclear sites
| Site | Country | Distance | Operating GW gross |
|---|---|---|---|
| Ohma nuclear power plant | Japan | 173 km | - |
How these are worked out: ranks use gross operating capacity; ages count from the start-up year on record, as on the age page; build times run from construction start to grid connection, as on the build-times page; ratings are the tracker's net and design net capacity, as on the uprates page. Distances are straight-line between exact positions, so a site with only an approximate position gets none. A unit missing a date or a rating is left out of the figure that needs it.
| Location | Hokkaido, Japan |
|---|---|
| Coordinates | 43.0367, 140.5125 |
| Elevation | about 20 mabove sea level |
| Setting | On the sea coast, 0.1 km from the water |
| Region | Eastern Asia |
| Units by status | Mothballed: 3 |
Elevation is read at the listed coordinates from a 30 m terrain model (SRTM 30 m). Two independent models differ by a median of 6 m across our plants and by up to about 40 m on steep or coastal ground, and a point on a shoreline can read as sea level. Distance to the water is measured to a generalised 1:10 million coastline, so a few kilometres or less is not resolved. This is context, not a design-basis or flood-risk figure.
| Owners | Hokkaido Electric Power Co Inc |
|---|---|
| Operators | Hokkaido Electric Power |
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Sources
- Global Nuclear Power Tracker, Global Energy Monitor, August 2026 release , CC BY 4.0 · retrieved 2026-09-06
- GEM.wiki entry (further reading) , CC BY-SA 4.0, linked, not quoted
How these sources are used, including the corrections applied on top of them and what is deliberately left blank · download the underlying data