Finnish Olkiluoto 3 nuclear reactor back on grid after disturbance

HELSINKI - Finland's new Olkiluoto 3 nuclear reactor reconnected to the national grid late on Monday following an 11-hour outage caused by a measurement error in a voltage regulator, operator TVO said.

The new and much-delayed reactor resumed test production on Aug. 28 after maintenance and upgrades, raising hopes it would assume regular service on Dec. 10 as its output is highly sought-after due to the energy crisis in Europe.

"Commissioning has continued again," TVO said in a tweet on Monday.

Under construction since 2005, the 1,600 megawatt (MW) OL3 was originally meant to start operation in 2009 but has faced several technical mishaps which sparked costly delays and a lengthy legal battle.