Finland's long-delayed Olkiluoto 3 reactor to come on stream in Jan

HELSINKI, Dec 16 (Reuters) - Finland's much-delayed Olkiluoto 3 nuclear reactor will come on stream on Jan. 22, its operator said on Thursday after national authorities issued a start-up permit.

Plagued by technological problems that became the subject of a lawsuit, the 1.6 GW plant had originally been due to link up to the power grid in 2009.

It will run at 30% of its regular output level during an initial test production phase, operator Teollisuuden Voima (TVO) (POHVOT.UL) said in a statement.

Regular electricity production is scheduled to start on June 6, TVO - owned by Finnish utility Fortum (FORTUM.HE) and a consortium of smaller energy and forestry companies - added.

Technological setbacks have delayed the third Olkiluoto reactor by more than a decade and driven TVO into a lengthy legal battle over compensation with the plant's builders, France's Areva and Germany's Siemens (SIEGn.DE).

Once fully operational, Olkiluoto 3 will meet 14% of Finland's electricity demand, TVO has said. Total Finnish installed power generation capacity was 17.6 GW in 2020, Finland's energy authority said.

Earlier on Thursday, Nuclear Safety Authority STUK granted TVO permission for making the reactor critical and conducting low power tests.

"Commissioning tests performed before the first criticality show that the plant operates as planned," STUK said.

Reporting by Essi Lehto and Nora Buli in Oslo; editing by Jason Neely and John Stonestreet

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