Europe's largest nuclear reactor starts production in Finland after 14 year delay

Finland’s much-delayed and costly new nuclear reactor – Europe's most powerful by production capacity – has completed a test phase lasting more than a year and started regular output on Sunday, boosting the Nordic country’s electricity self-sufficiency significantly. 

The Finnish island of Olkiluoto, where the third EPR nuclear reactor became operational on Sunday, making it the largest facility of its kind in Europe. The plant was built in cooperation with France's Areva Group, but experienced numerous delays in becoming operational over the past 14 years. Photo: Wikimedia Commons/Teollisuuden Voima Oy

 Built by the French-led Areva-Siemens consortium, the reactor was first started up in December 2021 and connected to the Finnish power grid in March last year.

Operator Teollisuuden Voima, or TVO, tweeted that “Olkiluoto 3 is now ready" after a delay of 14 years from the original plan.

"Test production has been completed and regular electricity production started today," TVO said. "From now on, about 30 percent of Finnish electricity is produced in Olkiluoto," which already had two reactors.

With a capacity of generating 1,600 megawatts, Olkiluoto 3 is the single largest nuclear reactor in Europe, while Ukraine's Zaporizhzhia plant, with its six reactors, is the largest nuclear plant.

It will help Finland to achieve its carbon neutrality targets and increase energy security at a time when European countries have cut oil, gas and other power supplies from neighbouring Russia.

In a statement, TVO President and CEO Jarmo Tanhua said: “The production of Olkiluoto 3 stabilizes the price of electricity and plays an important role in the Finnish green transition,” adding that “the electricity production volume of Europe’s largest nuclear power plant unit is a significant addition to clean, domestic production.”

Olkiluoto 3 is now ready.🎉
Test production has been completed and regular electricity production started today, Sunday, 16 April 2023.
From now on, about 30 % of Finnish 🇫🇮 electricity is produced in #Olkiluoto.⚡️
👉 https://t.co/5AuDVAthUV#OL3 #FinlandsGreatestClimateAct
🧵 pic.twitter.com/Gl13PUDN4d

— Teollisuuden Voima (@tvo_fi) April 15, 2023

Over a decade of technical and legal obstacles

Construction of Olkiluoto 3 began in 2005 and was due to be completed four years later.

However, the project was plagued by several technological problems that led to lawsuits.

The last time a new nuclear reactor was commissioned in Finland was more than four decades ago and the Olkiluoto 3 is Western Europe’s first new reactor in more than 15 years.

It is the first new-generation European Pressurized Reactor (EPR) to have gone online in Europe and was developed in a joint venture between France’s Areva and Germany’s Siemens groups. 

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Primarily because of safety concerns, nuclear power remains a controversial issue in Europe.

The launch of the Finnish reactor coincides with Germany’s move to shut down its last remaining three nuclear plants on Saturday. 

Experts have put Olkiluoto 3’s final price tag at around €11 billion – almost three times what was initially estimated.

Finland now has five nuclear reactors in two power plants located on the shores of the Baltic Sea.

Combined, they cover more than 40% of the nation's electricity demand.