OL nuke plant produces 23.26 TWh electricity in 2024

The Olkiluoto (OL) nuclear power plant produced a total of 23.26 TWh (Terawatt-hours or billion kilowatt-hours) of electricity in 2024, said the owner of the plant Teollisuuden Voima Oyj (TVO) in a press release on Friday.

The production is about 30 percent of the entire electricity consumption in Finland.

The newest of the Olkiluoto plant units, Olkiluoto 3 (OL3) produced 9.69 TWh of electricity to the national grid last year. Apart from the annual service outage carried out in the spring, OL3 was only out of production for a little over four days (108 h) during the whole year.

The only unplanned disruptions in production at the OL3 plant unit were caused by the failure of the differential pressure measurement in June and the malfunction of the generator’s sealing oil system in November.

The production year of the Olkiluoto 1 plant unit (OL1) can be characterised as a strong one, with an availability factor of 89.2 percent recorded for the unit. The plant was only out of production during the annual outages.

The production volume of Olkiluoto 2 (OL2) was limited by the generator failure detected in September. At 84.9 percent, the availability factor of the unit was lower than in previous years due to this failure.

The replacement of the generator rotor took 28 days. The plant unit has since then been operated at a lower power output level of 735 MW to reduce the risk of rotor failure.

In 2024, OL1 produced 6.95 TWh and OL2 6.62 TWh of electricity.

“The high reliability of OL3 was a positive point last year. Considering it was only the second year that the plant was in operation, the number of production disruptions was low also in international comparison,” said TVO’s Marjo Mustonen, Senior Vice President, Electricity Production.

“Our personnel has managed to master the plant unit with their excellent competence and well-functioning team work, and our experience in operational activities at the OL1 and OL2 plant units has been of paramount importance. The service outage also provided valuable knowledge for the future to us,” Mustonen added.

The production figures of the year 2024 did not reach a record level due to the extension of the annual outages and the generator fault in the turbine island of the OL2 plant unit.

The 2024 production in Olkiluoto would have been enough to cover the whole electricity consumption of Finland in 1970 when Finland used just under 21 TWh of electricity.