Finland may resume OL3 nuclear tests on Dec 11, operator says

OSLO (Reuters) - Test production of electricity at Finland's much-delayed Olkiluoto 3 nuclear reactor will restart on Dec. 11 at the earliest, while regular output is at best set to begin on Jan. 22, operator Teollisuuden Voima (TVO) said on Monday.

TVO in October revealed that cracks were found in the OL3 reactor's four feedwater pumps after test production, again delaying startup of the plant which was originally meant to begin operations in 2009.

The damage to the reactor is a setback for Finland, where the national grid operator has warned of heightened risk of power blackouts in the coming winter if OL3 could not reliably supply electricity.

Before the latest problems, OL3 had been due to start production on Dec. 27, but TVO last month said this date was no longer realistic.

In a regulatory filing on Monday, the start of test production was set to Dec. 11 while regular output was provisionally scheduled for Jan. 22.

"According to information from the Areva-Siemens plant supplier consortium, electricity production will continue on 11 December 2022 at the earliest, and as such regular electricity production starts at the end of January 2023 at the earliest," TVO said in a separate statement.

"The investigation into the damage at Olkiluoto 3's feedwater pumps will continue still for some weeks, and its impact on the schedule cannot be estimated," the company added.

(Reporting by Nora Buli, editing by Terje Solsvik)