Swedish nuclear operator OKG has decided not to push Oskarshamn 3 to its maximum capacity until 2011 for the sake of a secure electricity supply over the coming winter.
|Oskarshamn 3 (Image: OKG)
"OKG has decided, during the on-coming cold season, to prioritize the security of supply before the need of finalizing the trial operations program for the modernized Oskarshamn 3," the company announced. The boiling water reactor (BWR), which has undergone extensive modernization to enable it to increase its capacity from 1200 MWe to 1450 MWe, will now operate at a planned capacity of 1100 MWe over the winter. OKG says it hopes to resume trial operations, required before the unit can formally be operated at its new capacity, on 1 March 2011.
OKG has spent some €313 million ($455 million) on modernization work at Oskarshamn 3, including improvements to the reactor and turbines, since initial approval was granted in 2005. The unit was given regulatory approval for one year's trial operation at 1450 MWe in October 2009. This was to last until its next refuelling outage, when OKG would be required to submit another application for routine operation at the higher level.
The unit was to have entered the scheduled refuelling outage on 10 October, but recurring operational disturbances, such as problems with bearings in newly installed turbine equipment, saw the plant taken off line a month early on 10 September. However, provided the turbine equipment problems are solved, the plant's management still plans to be able to deliver energy equivalent to the unit's normal pre-modernization output through the winter.
Sweden's 10 operating nuclear reactors supply some 40% of its electricity. In the past, Swedish nuclear operators have faced criticism when outages have had to be extended into the cold winter months. Of Oskarshamn's two other BWRs, the 492 MWe unit 1 is currently also offline for its annual maintenance outage but is due to restart later this week, while the 661 MWe Oskarshamn 2 is working at full power. Researched and written
by World Nuclear News