Operator Teollisuuden Voima (TVO) has said that the Olkiluoto 3 (OL3) European Pressurized Water Reactor (EPR) plant unit in Finland has reached first criticality.

The move marks the commissioning of a new nuclear plant in the country after a gap of more than 40 years.

The OL3 will commence electricity production when it will be connected to the national grid at the end of January 2022.

Once regular electricity production starts, OL3 will deliver nearly 14% of Finland’s electricity.

Commenting on the activation, TVO Electricity Production senior vice-president Marjo Mustonen said: “This moment will forever be remembered as a demonstration of persistent work for the commissioning of our new plant unit. It reflects strong nuclear professionalism and a will to make Finland’s greatest act for the climate a reality.”

OL3 project director Jouni Silvennoinen said: “A wonderful highlight of the project was completed together with the plant supplier.

“Something even better is in store in January, when OL3 will be connected to the national grid, i.e., electricity production starts.”

OL3 is located at the western end of the Olkiluoto island besides the OL1 and OL2 units. The reactor’s net electrical output will be around 1,600MW.

After the unit starts, the power level will be gradually increased with commissioning tests at every level.

Electricity production will commence at a 25% power level. Regular electricity production is slated to commence in June 2022.