Olkiluoto nuclear power plant
Olkiluoto nuclear power plant is a nuclear power station in Finland with 3 operating units totalling 3,560 MW gross. The site has 4 units on record in total.
Units
| Unit | Status | Type | Model | Gross MW | Online |
|---|---|---|---|---|---|
| Unit 1 | BWR | AA-III, BWR-2500 | 920 | 1979 | |
| Unit 2 | BWR | AA-III, BWR-2500 | 920 | 1982 | |
| Unit 3 | PWR | EPR | 1,720 | 2023 | |
| Unit 4 | Cancelled | - | - | 1,830 | - |
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.
Olkiluoto nuclear power plant 1
| Reactor type | Boiling water reactor (BWR) |
|---|---|
| Model | ASEA-Atom BWR |
| Size class | Large |
| Gross capacity | 920MW |
| Net capacity | 890MW |
| Thermal output | 2,500MWt |
| Enrichment | 3–5% U-235 |
| NSSS vendor | not on record |
| Owner | Teollisuuden Voima Oyj100% |
| Operator | Teollisuuden Voima |
| Construction start | 1 Feb 1974 |
|---|---|
| First criticality | 21 Jul 1978 |
| Grid connection | 2 Sep 1978 |
| Commercial operation | 10 Oct 1979 |
Live status, outage record and fuel chain for Olkiluoto nuclear power plant 1
Olkiluoto nuclear power plant 2
| Reactor type | Boiling water reactor (BWR) |
|---|---|
| Model | ASEA-Atom BWR |
| Size class | Large |
| Gross capacity | 920MW |
| Net capacity | 890MW |
| Thermal output | 2,500MWt |
| Enrichment | 3–5% U-235 |
| NSSS vendor | not on record |
| Owner | Teollisuuden Voima Oyj100% |
| Operator | Teollisuuden Voima |
| Construction start | 1 Nov 1975 |
|---|---|
| First criticality | 13 Oct 1979 |
| Grid connection | 18 Feb 1980 |
| Commercial operation | 10 Jul 1982 |
Live status, outage record and fuel chain for Olkiluoto nuclear power plant 2
Olkiluoto nuclear power plant 3
GNPT gives a commercial operation date of 1 January 2022, before the unit's own grid connection on 12 March 2022. The World Nuclear Association database lists regular (commercial) operation from 16 April 2023, after the trial-operation period that followed the grid connection. The start year follows the commercial date.
commercial_operation:
2022-01-01 → 2023-04-16
· World Nuclear Association, Nuclear Reactor Database, Olkiluoto 3
· verified 2026-10-22
GNPT gives a commercial operation date of 1 January 2022, before the unit's own grid connection on 12 March 2022. The World Nuclear Association database lists regular (commercial) operation from 16 April 2023, after the trial-operation period that followed the grid connection. The start year follows the commercial date.
start_year:
2022 → 2023
· World Nuclear Association, Nuclear Reactor Database, Olkiluoto 3
· verified 2026-10-22
| Reactor type | Pressurised water reactor (PWR) |
|---|---|
| Model | EPR |
| Size class | Large |
| Gross capacity | 1,720MW |
| Net capacity | 1,600MW |
| Thermal output | 4,300MWt |
| Enrichment | 3–5% U-235 |
| NSSS vendor | Framatome |
| Owner | Teollisuuden Voima Oyj100% |
| Operator | Teollisuuden Voima |
| Construction start | 12 Aug 2005 |
|---|---|
| First criticality | 21 Dec 2021 |
| Grid connection | 12 Mar 2022 |
| Commercial operation | 16 Apr 2023 |
Live status, outage record and fuel chain for Olkiluoto nuclear power plant 3
Olkiluoto nuclear power plant 4 Cancelled
| Reactor type | not disclosed |
|---|---|
| Model | not disclosed |
| Size class | Large |
| Gross capacity | 1,830MW |
| Net capacity | not disclosed |
| Thermal output | not disclosed |
| Enrichment | not established |
| NSSS vendor | not on record |
| Cancelled | 2015 |
| Milestones | no dates on record |
|---|
Olkiluoto nuclear power plant in context
By gross operating capacity Olkiluoto nuclear power plant is the 1st largest of 2 operating nuclear sites in Finland, holding 77% of the country's operating capacity, and ranks 33rd of 172 worldwide.
Its operating units started up between 1979 and 2023; the median unit is 44.0 years old, younger than the median of 45.0 in Finland.
The 3 units with both construction and grid dates on record took 4.3 to 16.6 years (median 4.6) from construction start to grid connection; the median across all reactors connected in the 1980s is 7.3 years.
The nearest other tracked nuclear sites are Forsmark nuclear power plant (200 km) and Loviisa nuclear power plant (283 km).
2 operating units are rated differently now from their design net capacities: Unit 1 +34.8% and Unit 2 +34.8%.
Build time by unit
| Unit | Construction start | Grid connection | Years | Fleet median, same decade |
|---|---|---|---|---|
| Unit 1 | 1974 | 1978 | 4.6 | 5.4 (1970s) |
| Unit 2 | 1975 | 1980 | 4.3 | 7.3 (1980s) |
| Unit 3 | 2005 | 2022 | 16.6 | 7.7 (2020s) |
Nearest tracked nuclear sites
| Site | Country | Distance | Operating GW gross |
|---|---|---|---|
| Forsmark nuclear power plant | Sweden | 200 km | 3.4 |
| Loviisa nuclear power plant | Finland | 283 km | 1.1 |
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.
Earthquakes nearby
Loading the latest USGS check…
| Time (UTC) | Mag | Depth | Epicentre | Distance |
|---|
Magnitude 4.0 and above within 200 km of Olkiluoto nuclear power plant's listed coordinates, past 30 days. This is distance, not shaking: it says nothing about damage or any change in operation. Every plant.
| Location | Satakunta, Finland |
|---|---|
| Coordinates | 61.2371, 21.4433 |
| Elevation | about 5 mabove sea level |
| Setting | On the sea coast, 2 km from the water |
| Region | Northern Europe |
| Units by status | Operating: 3 Cancelled: 1 |
Elevation is read at the listed coordinates from a 30 m terrain model (ASTER GDEM 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 | Teollisuuden Voima Oyj |
|---|---|
| Operators | Teollisuuden Voima |
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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