Everllence Signs Long-Term Service Agreement for Finnish Nuclear Power Plant

Four-year contract includes maintenance of Pielstick back-up engines at Olkiluoto 3 nuclear-power plant

March 11, 2026

Everllence PrimeServ has announced the signing of a Long-Term Service Agreement (LTSA) with TVO, operator of the Olkiluoto 3 nuclear-power plant - one of the most iconic sites in the European nuclear programme.

The Finnish power plant recently entered operation and must meet particularly high reliability, safety and security requirements, making equipment maintenance a major challenge. It is equipped with four Pielstick 18 PA6 B engines as a back-up power source. Despite their low operational demands, these must be maintained to the highest standards.

The four-year contract between Everllence PrimeServ and TVO comprises:

• intermediate maintenance of the emergency units;
• monthly performance tests of the engines.


SEMT Pielstick PA6 B engine SEMT Pielstick PA6 B engine.   Image by Everllence.

The contract is a turnkey solution that covers the dismantling, cleaning, reconditioning and replacement of parts, and reassembly with a maximum completion time of 30 days per unit. This mobilises around 15 specialists on site.

Laurent Cado, PrimeServ Sales Manager, Everllence France, said: "The success of this contract is based on the coordination and responsiveness of the Everllence teams, who are capable of combining technical expertise, rigorous planning and execution in demanding conditions. For TVO, this guarantees a reliable and committed partner capable of ensuring the availability of its strategic equipment."

This project confirms Everllence PrimeServ's ability to tackle major technical challenges where safety, quality, and meeting tight deadlines are crucial, and to support its customers over the long term.

Everllence - Press Release