STOCKHOLM — A nuclear reactor in southern Sweden has been shut down after a fire at the plant.
“A fire alarm went off around midnight and our own firefighters were able to locate the fire in the turbine hall and quickly extinguish it,” Anders Oesterberg, a spokesman at the Oskarshamn nuclear power plant, told AFP.
The cause of the fire was not immediately known, but an oil leak in the turbine was seen as a possible cause, Oesterberg said.
Ostberg said Sunday the blaze appears to have been caused by oil that leaked onto a hot surface.
But he said further investigations are needed to determine what caused the oil leak and that it wasn’t immediately clear when the nuclear plant would reopen.
OKG operates 3 nuclear reactors in the town of Oskarshamn in southeast Sweden.
The country began research into nuclear energy in 1947 with the establishment of the Atomic Energy Research Organization. In 1964, the country built its first small heavy water reactor. The government decided to use hydropower and supplement it with nuclear energy to avoid falling victim to the perennial volatility in oil prices. Six nuclear reactors began commercial service in both the 1970s and 1980s, with one unit closed in 1999 and another in 2005.
The Nuclear power station Oskarshamn is one of three active nuclear power stations in Sweden. The plant is about 30 kilometers north of Oskarshamn directly at the Kalmarsund at the Baltic Sea coast and with three reactors producing about 10% of the electricity needs of Sweden. All reactors use BWR technology.
Unit 1 has an installed output of 487 MW, Unit 2 627 MW, and Unit 3, the newest reactor block at the facility, has an installed output of 1,194 MW. The nuclear power station Oskarshamn is thereby one of the largest power stations in the Nordic area by production.
On July 25, 2006, Units 1 and 2 were shut down as a precaution after a safety-related incident at an identical reactor at the Forsmark nuclear power plant. The incident related to a failure of diesel generators to automatically start up when required. Modifications were later made to all the plants to address the issue.
On May 21, 2008, according to the Norwegian newspaper article in Aftenposten, the Swedish Aftonbladet and the Swedish The Local paper, a welder was caught on the entrance security check with trace elements of explosives on a carrier bag and his hand. 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 and the event had no relevance to the operation of the plant or nuclear safety.
Both Unit 2 and 3 are currently undergoing power and security upgrades. Unit 3 is planned to become the most powerful BWR in the world at approximately 1450MWe. The maximal reached output so far is 1260 MWe. Due to the upgrade, the reactor has been on and off the grid with prolonged maintenance outages throughout 2010. Unit 2 will be upgraded in several steps and will reach maximum capacity of thermal power 2,300 MW and 840 MWe in 2011.