Both units at Fortum’s Loviisa nuclear power plant are back in production after their annual maintenance outages. The annual outage of Unit 1 lasted approximately 22 days, until August 27. All scheduled work at Unit 1 was completed on time. However, the total duration of the annual outage was exceeded by approximately two days due to malfunction of a valve during start-up. The maintenance outage of Unit 2 lasted approximately 17 days, until 21 September. All scheduled work was completed one day ahead of schedule. Start-up of unit 2 was prolonged 12 hours due to trip of feedwater pumps during turbine start-up.
According to Fortum, this year both units underwent a refueling outage. In conjunction with the annual outages, about one quarter of the fuel in both units was replaced.
In addition to the normal periodic maintenance tasks and refueling, the most significant work on both units this year is the renewal of the high-pressure safety injection pump motors. At Loviisa Unit 1, also a modernised high-pressure turbine was installed and at Unit 2, two turbine moisture separators were replaced.
“This year several challenging projects were successfully implemented at both units, thanks to high quality planning. Overall, the work went smoothly,” said Anssi Laakso, Manager, Plant Lifetime Management and Maintenance unit.
Good results have been achieved in the long-term development efforts to lower the radiation levels at the plant during the annual outage. Thanks to the continuous development work, the collective radiation doses for personnel during annual outage at Unit 1 were the lowest in the plant’s history and among the lowest for Unit 2 compared to similar types of outages.
“At the power plant, tidiness and good order are prerequisites for an efficient and safe working environment. In our daily operation we pay attention to them, and especially during annual outage when the number of employees and work to be done is multiplied in comparison with normal operation. A great step forward was taken in managing the premises and work sites. This is one of the contributing factors why no injury related loss of workdays occurred during this annual outage,” Laakso said.
A total of some 700 external employees participated in the Loviisa power plant’s annual outage that started in August and in ongoing modernisation projects. About 80 percent of the workers were Finnish subcontractors. There are approximately 500 Fortum employees and some 100 permanent contractors working at the Loviisa power plant year round.