The OL3 EPR plant unit’s permission application for making the reactor critical and conducting low power tests has been submitted to the Radiation and Nuclear Safety Authority

Teollisuuden Voima Oyj (TVO), together with the plant supplier AREVA-Siemens consortium, has established that the OL3 EPR project has progressed faster than previously communicated. On this basis, TVO has submitted a permission application for making the reactor critical and conducting low power tests to the Radiation and Nuclear Safety Authority in Finland (STUK) today on Wednesday, December 8, 2021. Once the permission has been granted, TVO will communicate its potential effects on the schedule for starting electricity production. 

Making the reactor critical means starting the chain reaction, i.e., launching the reactor. As a result of the chain reaction, i.e., splitting atomic nuclei, heat is produced in the reactor. Water vapor produced with the heat is utilized to rotate the turbine. The kinetic energy of the turbine is then transformed into electricity in the generator. During the low power tests, the plant unit is however not yet connected to the national grid. 

Once STUK has granted the permission for making the reactor critical and conducting low power tests to the OL3 EPR plant unit, TVO will communicate its potential effects on the schedule for starting electricity production. 

The OL3 EPR plant supplier consortium is constructing the plant unit under a fixed-price turnkey contract. The supplier consortium companies, AREVA GmbH, AREVA NP SAS, and Siemens AG, have joint and several liability for the contractual obligations until the end of the guarantee period of the plant unit.

Further information:
Marjo Mustonen, Senior Vice President, Electricity Production

Interview requests:
Johanna Aho, Head of Communications, tel. +358 40 7290822

Teollisuuden Voima Oyj has produced electricity for its shareholders, Finnish industrial and energy companies, safely and reliably for 40 years. Nuclear electricity generated at TVO's Olkiluoto plant covers approximately one sixth, increasing to nearly one third once Olkiluoto 3 EPR is completed, of the electricity consumption in Finland. Climate-friendly nuclear electricity not only benefits society but also reduces the environmental impact of energy production. Moreover, the world's first final disposal facility for spent nuclear fuel is under construction in Olkiluoto.