Finnish utility Teollisuuden Voima Oyj (TVO) has completed its final acceptance unit 3 of the Olkiluoto NPP (OL3). The Areva-Siemens consortium constructed the OL3 plant – a 1,600 MWe EPR – under a fixed-price turnkey contract.
OL3 began regular electricity production in April 2023 following the completion of trial operation. 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 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, causing further delays.
During its first outage in April, technical problems resulted in delays in restarting the unit after fuel unloading took more time than planned and additional fuel inspections were required.
TVO and the Areva-Siemens consortium had joint liability for the contractual obligations until the end of the two-year warranty period of the unit, which is when the final acceptance of the plant unit took place.
Marjo Mustonen, TVO Senior Vice President for Electricity Production, said Olkiluoto 3 (OL3) had “operated reliably during the first two years. The annual outage this spring, the second one at the unit, was also completed successfully. The Final Takeover of OL3 was based on the fulfilment of the terms and conditions laid down in the Plant Supply Contract, but the many benefits we promised OL3 would bring to society have been realised already since 2023”.
TVO said OL3 had helped make Finland nearly self-sufficient in electricity and “contributes to the stability of the electricity price, and as Finland’s greatest climate act, also accelerates the clean transition towards a carbon-neutral society”.
TVO is 27% owned by Fortum and 57% owned by Pohjolan Voima Oy comprising mostly heavy industry, the major shareholders being pulp and paper manufacturers UPM Oyj and Stora Enso Oyj.
For French Government Shareholding Agency (Incarner l’État actionnaire) the handover of the first commercially operated EPR in Europe was a “historic moment for the French nuclear industry”. It posted on Linkedin that it marked a major milestone for Areva, “whose activities were refocused on the completion of the OL3 reactor after the restructuring of the French nuclear sector in 2015”. It added: “The collective experience gained from this project will directly contribute to the development of the EPR technology, which remains a strategic priority for France and its industry.”
