Operator Teollisuuden Voima (TVO) said the 1,600-MW plant, supplied by an Areva-Siemens consortium, was connected to the grid at 13:01 local time on Saturday 12 March and power output has been gradually increased to approximately 27%.
During a test production phase of about four months, the unit’s power output will be gradually increased to the maximum 1,600 MW. Regular electricity production is scheduled to begin in July 2022.
Once fully operational Olkiluoto-3 is expected to meet 14% of Finland’s electricity demand, potentially reducing the need for imports from Russia, Sweden and Norway.
Russia accounted for roughly half of coal imports, 10% of electricity imports and two-thirds of both oil and natural gas imports to Finland in 2020, according to statistics compiled by the Finnish Energy Industry Association.
TVO said the plant, which reached first criticality on 21 December, will significantly improve Finland’s electricity self-sufficiency. The last commercial nuclear plant to begin operation in Finland was Olkiluoto-2 in July 1982.
The project has seen a number of delays and cost revisions. Construction of the plant, which began in August 2005, has been running about 10 years behind schedule. In August 2021 TVO said regular electricity production had been postponed for three months due to an extended turbine overhaul and inspection works. In February 2022, electricity production was pushed back again because of modifications needed following an earlier testing phase.
The cost of Olkiluoto-3 was initially put at €3.2bn, but in 2012 Areva estimated the overall cost at closer to €8.5bn. Since then, it has not made public any updated cost projection. TVO told NucNet in an email it would not comment on the cost of the facility.