In a statement on Sunday, the head of Teollisuuden Voima (TVO), the operator of the Olkiluoto 3 (OL3) nuclear reactor in southwest Finland, announced the reactor had come online and begun electricity production

Although regular output was scheduled to begin on Monday, following a lengthy testing phase at the Eurajoki facility, the unit was brought online and production began at 2AM on Sunday.

At 1.6 gigawatts, the unit is the most powerful nuclear reactor on the continent, and the third largest on the globe. It is expected to meet about 14% of Finland’s electricity demand, and operate for at least 60 years.

Tanhua stated, “The production of Olkiluoto 3 stabilizes the price of electricity and plays an important role in the Finnish green transition.”

With its construction beginning in 2005, the reactor was slated to begin producing electricity in 2009, however setbacks in the design process and a series of legal battles ended up delaying its launch by 14 years.

In March of last year, the OL3 reactor was hooked up to Finland’s power grid, and began test production, however several operational glitches delayed the reactor’s transition to regular operation several times.

OL3 becomes the third reactor at the Olkiluoto nuclear power plant. The other two units, OL1 and OL2 were commissioned in 1978 and 1980 respectively. In 2021, the Olkiluoto facility generated 14.4 terrawatt hours of power, which fulfilled about one sixth of Finland’s total electricity consumption.

Finland hopes to now see its reliance on electricity imports from Norway and Sweden reduced due to the new reactor. It is also hoped it will help to make up for electricity supplies which were lost after Russian utility Inter RAO cut off power, following Finland’s failure to pay for previously supplied electricity, amid political conflicts over the war in Ukraine, and how payments should be made.