Loviisa nuke plant resumes production after annual outage

Both units at Fortum’s Loviisa nuclear power plant are back in production after completion of their annual outages, said Fortum in a press release on Monday.

Unit 2 underwent an extensive annual outage, which is done every 4 years; the outage lasted just over 36 days and was completed on September 12.

The short annual outage of Unit 1 lasted 29 days and was completed on October 16.

The annual outage of Unit 2 was delayed by about five days from the original plan. The delay was caused by the replacement of a main reactor coolant pump, which had failed during the start-up phase, with a serviced pump.

The annual outage of Unit 1 was delayed by about a week due to a leak in the main reactor coolant pump’s sealing water line, detected during a leak test.

“It was a normal annual outage-related test procedure. The purpose of the test is to verify leak-tightness of the systems that are part of the primary circuit after servicing and before plant start-up,” said Sasu Valkamo, Vice President of Loviisa nuclear power plant.

In addition to the normal periodic maintenance work and refuelling, tasks related to maintenance and continuous improvement were carried out on both units during the annual outage. 

“For example, the automation modernisation of Loviisa Unit 1’s emergency generators, which was started in the previous annual outage, was continued. In the modernisation project, the original automation systems are being replaced with digital systems,” Valkamo added.

In conjunction with the annual outages, about one quarter of the fuel in both units was replaced.

In addition to 530 power plant employees, about 750 external workers also participated in the annual outage.