The number-two reactor at the Olkiluoto nuclear power plant in western Finland will reconnect to the national power grid on Tuesday afternoon, plant operator Teollisuuden Voima (TVO) said on Friday.
Olkiluoto 2 (OL2) is to re-start four days earlier than previously estimated. It has been offline to facilitate the replacement of a faulty generator rotor.
On Monday, the plant’s biggest unit, Olkiluoto 3 (OL3), also came back online earlier than expected after annual maintenance. Last spring, OL3 – Europe’s largest reactor – saw its maintenance drag on some five weeks longer than expected.
Finnish electricity 39% nuclear
Altogether Olkiluoto generates about 28 percent of the electricity used in Finland, so service outages can have significant impacts on the supply and price of electricity in the country.
In total, nuclear power accounted for 39 percent of Finland's electricity consumption last year, according to the Ministry of Economic Affairs.
OL2 will only be back in service for a couple of weeks before it is shut down again for annual maintenance on 25 May. Before that, the Olkiluoto 1 unit will go offline for maintenance beginning 11 May. The annual outages will continue into June.
The plant’s two oldest units were completed in 1979 and 1982, respectively.
Ageing reactors to get more replacement parts
Earlier this week, TVO announced that it had secured funding for upgrades to extend the two reactors' functional lives. The project will include the replacement of the instrumentation and control (I&C) and monitoring systems as well as the reactor steam separators at the OL1 and OL2 plant units.
"These investments are designed to further improve the safety and availability of our plant units. The possible extension of the service life of the plant units as well as an increase of their thermal power have also been accounted for in the investment plans," TVO’s Senior Vice President for Engineering, Mikko Lampinen, said in a press release on Tuesday.
TVO and the Nordic Investment Bank (NIB) have signed a 75-million-euro loan agreement to finance the project. Altogether there is to be some 150 million euros in external financing for it.
The company submitted an environmental impact assessment for the project to the Ministry of Economic Affairs in December. In April, the ministry gave its preliminary green light for the project to move ahead. It remains unclear how long the project will take and by how much the two ageing units' lifespans can be extended.
