Finland’s Finland’s radiation and nuclear safety authority, Stuk, has identified further safety issues at unit 3 of the Olkiluoto NPP (OL3), which will need to be rectified before the unit can receive a permit to operate, Stuk told Reuters on 22 February. The 1,600MWe EPR being built by Areva (now Framatome) is already more and a decade behind schedule and significantly over budget.
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. “The test results show that these vibrations are not approved,” Valikangas told Reuters. “This must be taken care of before the ministry decides on the permit,” Valikangas said, adding that Stuk would offer two options for a solution. Stuk will publish 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. “I do not know if it will delay the reactor. There is still time in the testing programme 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. There was no suggestion that the problem identified at Olkiluoto 3 would affect other EPR reactors.
The project has faced a series of delays. The latest, announced last November, entitled the Finnish operator TVO to a payment of €18 million ($20.4 million) from Areva. In March 2018, Areva settled a long-running dispute with TVO by agreeing to pay €450 million for cost overruns and delays. It also agreed to pay a further €20 million for each additional month of delays from I January 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 a few months but Stuk said the problem remains unsolved. 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 told Reuters. He could not say whether that would secure the required permit, adding that Olkiluoto 3 could not start loading fuel before receiving that approval.
TVO’s owners include utility company Pohjolan Voima, its rival and Nordic electricity major Fortum, EPV Energia, Loiste Holding and Kemira.