
The Oskarshamn Nuclear Power Plant is one of three active
nuclear power
Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced by ...
stations in Sweden. The plant is about north of
Oskarshamn
Oskarshamn is a coastal city and the seat of Oskarshamn Municipality, Kalmar County, Sweden with 17,258 inhabitants in 2010.
History
Etymology
Döderhultsvik was the original name before a town charter was granted in 1856. The name was then chan ...
, directly at the
Kalmarsund at the
Baltic Sea
The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by the countries of Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden, and the North European Plain, North and Central European Plain regions. It is the ...
coast and with one active reactor, producing about 10% of the electricity needs of Sweden. All reactors were built using
BWR technology.
Unit 1 had an installed output of 494 MW and Unit 2 664 MW; these are now decommissioned. Unit 3, the newest reactor block at the facility, has an installed output of 1,450 MW.
Clab, the temporary storage facility for
spent nuclear fuel
Spent nuclear fuel, occasionally called used nuclear fuel, is nuclear fuel that has been irradiated in a nuclear reactor (usually at a nuclear power plant). It is no longer useful in sustaining a nuclear reaction in an ordinary thermal reactor and ...
from all Swedish reactors, is also located at the site.
Operator
The responsible utility is
OKG, short for the ''Oskarshamnsverkets Kraftgrupp AB'', which was acquired by
Sydkraft in 1993, (later: ''
E.ON Sverige'').
Uniper
Uniper SE is a German multinational energy company based in Düsseldorf, Germany, which has been a state-owned enterprise since late 2022. It is one of the biggest energy companies by revenue in Europe. The name of the company is a portmanteau o ...
owns 54.5% and the other partner
Fortum
Fortum Oyj is a Finland, Finnish Government of Finland, state-owned energy company located in Espoo, Finland. It mainly focuses on the Nordic countries, Nordic region. Fortum operates power plants, including co-generation plants, and generate ...
45.5% of OKG.
History
On 23 September 2003, Unit 3 of the reactor was shut down due to mechanical problems, and together with a failure that occurred in a high voltage substation, this caused a
power outage affecting five million people in southern Sweden and east Denmark.
On July 25, 2006, Units 1 and 2 were shut down as a precaution after a safety-related incident at a similar reactor at the
Forsmark plant. The incident related to a failure of diesel generators to automatically start up when required, after a blackout caused by a shortcut at the grindgear sections at the plant. Modifications were later made to all the plants to address the issue.
On May 21, 2008, a welder tested positive for trace elements of explosives on a carrier bag and his hand at the entrance security check. The same evening Reactor 1 of the facility was shut down to allow bomb teams to sweep the facility. With police investigations ongoing, Kalmar police spokesperson Sven-Erik Karlsson confirmed to the TT news agency that a welder on his way in to the plant on Wednesday morning was caught with a relatively small amount of a highly explosive substance. The substance was later shown to be from
nail polish
Nail polish (also known as nail varnish in British English or nail enamel) is a lacquer that can be applied to the human Nail (anatomy), fingernails or toenails to decorate and protect the nail plates. The formula has been revised repeatedly t ...
and the event had no relevance to the operation of the plant or nuclear safety.
During 2010 Unit 2 underwent power and security upgrades. Unit 3 was after many upgrades the most powerful
BWR in the world at approximately 1450 MW
e. Due to the upgrade, the reactor had been on and off the grid with prolonged maintenance outages throughout 2010. Unit 2 was upgraded in several steps and was planned to a reach maximum capacity of thermal power 2,300 MW and 840 MW
e, but was closed before all upgrades had been performed.
[
]
On September 30, 2013, a portion of the plant (the third reactor) was closed when a group of
jellyfish
Jellyfish, also known as sea jellies or simply jellies, are the #Life cycle, medusa-phase of certain gelatinous members of the subphylum Medusozoa, which is a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animal ...
clogged the cooling water intake pipes. It was not indicated as to whether the event had been classified as a safety disturbance yet, and to what level on the scale used for nuclear plants.
A decision on premature shutdown of units 1 and 2 was made in 2015. The decision entailed that there would be no future investments at unit 2 and the reactor would not be restarted.
Unit 1 was originally set for decommissioning on June 29, 2017, but it was closed prematurely due to an "operational disturbance" on June 17, 2017. It was decided not to restart the unit ahead of the shutdown scheduled for June 29, 2017.
In December 2018 a strategy was outlined for the "radiological demolition" of units 1 and 2 to be carried out between 2020 and 2028. This will allow the land to be used for other nuclear power related purposes.
The site has its own hydrogen production as the coolant for all 3 reactors, capable of making 12 kg per day. With the closure of reactor 1 and 2, surplus capacity is available, and an agreement to supply so-called
pink hydrogen to gas company
Linde was made in January 2022.
Between April and August 2025, the plant is shut down while a leak in the primary cooling system is being repaired.
See also
*
Nuclear power in Sweden
The electricity sector in Sweden has three operational nuclear power plants with 6 operational nuclear reactors, which produce about 30% of the country's electricity. The nation's largest power station, Forsmark Nuclear Power Plant, has three rea ...
*
List of power stations in Sweden
*
Template:Sweden nuke plant map
References
External links
* http://www.okg.se/
{{Authority control
Oskarshamn
Radioactive waste repositories
Nuclear power stations in Sweden
Uniper
Companies based in Kalmar County
Fortum
Buildings and structures in Kalmar County
1972 establishments in Sweden
20th-century establishments in Kalmar County