By Lefteris Karagiannopoulos
OSLO (Reuters) – Finland’s nuclear regulator has identified a safety issue at Olkiluoto 3, a 1.6-gigawatt reactor built by France’s Areva, now renamed Orano, and the problem needs to be fixed before the unit can receive a permit to operate, the regulator told Reuters.
The reactor is due to start producing electricity in January next year after a decade-long delay.
Part of the pressuriser, a primary circuit component of the reactor, is vibrating at levels that exceed safety limits, said Pekka Valikangas, the regulator’s section head for nuclear reactor regulation, ahead of an important assessment which is due to be published on Monday.
“The test results show that these vibrations are not approved,” Valikangas said in an interview.
The safety assessment by STUK, Finland’s radiation and nuclear safety authority, is a key report that will influence the government’s decision on whether to grant Olkiluoto 3 an operation permit.
“This must be taken care of before the ministry decides on the permit,” Valikangas said, adding that the regulator would offer two options for a solution. The reactor’s owner, Finnish consortium TVO, and supplier Orano would need to choose from those options.
STUK is also expected to publish on Monday its recommendation to the Ministry of Economic Affairs and Employment, which decides energy policy and will rule on the reactor’s permit.
Valikangas said he could not tell whether the development would lead to further delays, adding it was up to Areva and TVO to fix the problem on time.
“I do not know if it will delay the reactor. There is still time in the testing program to fix it,” he said.
The part of the pressuriser that needs fixing is the pipeline, which is related to the reactor’s cooling system and was supplied by Areva, Valikangas said. This component is responsible for balancing pressure in the reactor.
He did not elaborate on the two solutions STUK had identified and said further details would be made public on Monday.
There was no suggestion that the problem identified at Olkiluoto 3 would affect other reactors.
The facility in western Finland, already more than a decade behind schedule, has sustained several delays. The latest, announced last November, entitled the Finnish operator to a payment of 18 million euros ($20.4 million) from Areva.
Before that, in March, Areva settled a long-running dispute with TVO by agreeing to pay 450 million euros for cost overruns and delays. It also agreed to pay a further 20 million euros for each additional month of delays from Jan. 1, 2020.
The reactor previously experienced vibration issues which delayed hot testing in the first half of 2018. TVO said then that they would be fixed within few months but STUK said the problem remains ahead of the permit decision.
TVO said it had identified the problem and been working with Areva on a fix, which it expected to have in place during spring.
“We have been testing different options. We have a solution for that. There are two support system options and we have picked the right one … We need to show STUK that it works,” a TVO spokesman said.
He could not say whether that would secure the permit TVO needs, adding that Olkiluoto 3 could not start loading fuel before receiving that approval.
Orano was not immediately available for comment.
Finland needs the reactor as it imports more than 25 percent of its electricity from neighboring Sweden and Russia, while its energy needs are growing.
TVO’s owners include utility company Pohjolan Voima, its rival and Nordic electricity major Fortum, EPV Energia, Loiste Holding and Kemira.