After 18 years of a project that turned into a never-ending soap opera, the Olkiluoto 3 nuclear reactor on Finland's southwest coast has completed its production testing phase and is now fully operational, its operator, TVO, announced.

Built by the French group Areva with the German Siemens, it thus becomes the most powerful nuclear reactor in operation in Europe.

"The tests are completed and the regular production of electricity has begun," said TVO, which started commercial operation on the night of Saturday to Sunday.

Including the two existing old reactors 1 and 2, "about 30 percent of Finland's electricity is now produced in Olkiluoto," he added.

On Sunday around 09:30 GMT, more than half of Finland's electricity came from the atom.

Construction of the 1,600-megawatt reactor, which alone provides about 14% of Finland's electricity generation, began in 2005.

Global nuclear: stop or again? © Nalini LEPETIT-CHELLA / AFP

It had already been started at the end of December 2021 and reached its full electrical power of 1,600 megawatts for the first time on September 30.

Trials, themselves marked by delays, had been going on for several months.

Launched in 1992 as the ultimate in French nuclear technology, the European Pressurized Reactor (EPR) was designed to revive nuclear energy in Europe, in the aftermath of the 1986 Chernobyl disaster.

The new model is touted as offering both higher power and better safety, but its construction is proving to be a headache, and not only in Finland.

Debacle for Areva

In France, the construction of the Flamanville EPR, which began in 2007, was also affected by massive delays, due in particular to anomalies in the steel cover and reactor vessel.

The EPR has also been selected for a two-reactor power station at Hinkley Point in south-west England.

Electricity production is currently planned for mid-2027, instead of 2025 initially.

Two EPR reactors have already been commissioned in China, making Olkiluoto the third in operation in the world.

The Neckarwestheim nuclear power plant on April 9, 2023 in southern Germany © THOMAS KIENZLE / AFP/Archives

The enormous additional costs of the Finnish project started in 2005 were one of the main causes of Areva's industrial dismantling, weighed down by losses of several billion euros.

A structure remains, whose essential task is to complete the Olkiluoto project, but most of the group has passed into the fold of EDF.

Despite the Olkiluoto fiasco, support for civil nuclear power has grown in recent years in Finland, spurred by climate concerns and global energy tensions.

According to a poll published in May, 60% of Finns are now in favour, a record.

Coincidentally, the entry into commercial service of the Finnish EPR comes at the same time that Germany has shut down its last three reactors.

The Isar 2 (southeast), Neckarwestheim (southwest) and Emsland (northwest) power plants were disconnected from the power grid before midnight (22 GMT), as planned.

Their shutdown marks the culmination of more than 20 years of phasing out atomic energy in the country, despite controversies and the recent energy crisis in Europe.

This strategy of renouncing the atom, perceived as dangerous by large sections of the population, baffles many of Germany's partners, such as France, who believe that nuclear power has a role to play in decarbonizing electricity production.

The energy crisis triggered by the war in Ukraine has revived nuclear power, with its excellent carbon footprint, as an alternative to fossil fuels, including Russian gas.

© 2023 AFP