Automation adjustments delay OL3 grid connection

14 February 2022

The connection of unit 3 at the Olkiluoto nuclear power plant in western Finland to the national grid has been delayed until next month, operator Teollisuuden Voima Oyj (TVO) has announced.

Olkiluoto 3 (Image: TVO)

In late January, following an unplanned automatic trip during commissioning tests, TVO said the EPR plant would be connected to the grid in the first half of February, instead of the end of January as previously expected.

The expected start of regular electricity production remained unchanged as June. Earlier this month, the utility announced grid connection had been postponed until the end of February due to necessary modifications, and that regular electricity production would start in July.

TVO has now announced a further delay, saying: "During the OL3 plant unit's test production phase, it was observed that there is a need for modifications in the plant unit's automation, especially turbine island related control functions, as well as further testing related to the modifications.

"The modifications and the tests are taking longer than previously communicated and the schedule has now been updated accordingly."

The Areva-Siemens consortium is constructing the OL3 plant under a fixed-price turnkey contract. They have joint liability for the contractual obligations until the end of the guarantee period of the unit. Construction of Olkiluoto 3 began in 2005.

Completion of the reactor was originally scheduled for 2009, but the project has had various delays and setbacks.

The Finnish government granted an operating licence for OL3 in March 2019. Finland's nuclear regulator, STUK, granted a fuel loading permit in March 2021. Fuel loading was completed on 1 April, at which point an October start-up was envisaged.

However, this was postponed to allow for extra turbine overhaul and inspection works by the plant supplier. The reactor reached first criticality on 21 December. Electricity production will start when a 30% power level is reached.

Researched and written by World Nuclear News