Finland’s Teollisuuden Voima (TVO) said the EPR reactor at unit 3 of the Olkiluoto NPP (OL3) had begun regular electricity production following the completion of trial operation. In the future, about 30% of Finland's electricity will be produced from the Olkiluoto NPP, with OL3 accounting for 14%, TVO added noting that OL3 makes Finland almost self-sufficient in electricity. The plant unit will operate for at least the next 60 years. The first annual maintenance will be carried out in March 2024.
The Areva-Siemens consortium constructed the OL3 plant under a fixed-price turnkey contract and is responsible for the obligations of the plant supply contract until the end of the plant unit's warranty period. TVO said the OL3 project ends contractually when the analyses of the latest trial operation phase are completed and TVO is ready to make the appropriate decisions about receiving the plant unit and starting commercial use. “Decisions will be made shortly.”
Construction of OL3 began in 2005 and various setbacks and delays mean the plant is some 14 years behind the original schedule and significantly over budget. OL3’s final price tag is put at some $11bn ($12bn), some three times what was initially estimated. OL3 attained first criticality in December 2021 and was connected to the grid on in March 2022. The 1600 MWe EPR was operated at full capacity for the first time in late September 2022. However, cracks were identified in the impellers of the feedwater pumps located in the turbine island.
Tests at full power were continued after extensive investigations with two cracked impellers and two spare impellers. To avoid the recurrence of similar damage, impellers with more robust measurements were designed for OL3. New impellers were installed in all four of OL3’s feedwater pumps during a recent scheduled outage and the plant supplier carried out inspections in preparation for resumed trial operation. The reactor was briefly back in test mode in late December and early January before being closed again for maintenance.
TVO CEO, Jarmo Tanhua, said production at OL3 “stabilises the price of electricity and is an important part of Finland's green transition”. The electrification of society continues and environmentally friendly electricity production is certainly one of Finland's most important trump cards, says CEO. Production manager Marjo Mustonen said: “This is a historic day, the benefits of OL3 we promised for Finnish society will be realised.”
People from more than 80 different countries worked on the Olkiluoto 3 project, TVO noted. At its peak, the site strength was 4,500 employees. During the nuclear test operation phase alone, approximately 3,300 tests were performed and more than 9,000 test reports were prepared. The project had significant regional economic effects, especially in the Satakunta area. When the project started, about 60% of Finns supported nuclear power. This has now increased to 83%, according to TVO, which is owned by a consortium of power and industrial companies, the biggest shareholders being Pohjolan Voima (58.5%) and Fortum (25.8%).
Image: Olkiluoto nuclear power plant (courtesy of TVO)
