The regular electricity production from the Olkiluoto-3 reactor, which will be operated by Finnish utility Teollisuuden Voima (TVO), will be further delayed from end of 2018 as many important tests are due to be carried out, TVO said.

A consortium led by French state-owned nuclear group Areva is developing the third plant unit as part of a fixed-price turnkey contract signed with TVO in 2003.

As part of the deal, Areva-Siemens consortium was initailly scheduled to develop the first Generation III+ EPR reactor at the Olkiluoto 3 site by 2009.

TVO OL3 Project senior vice-president Jouni Silvennoinen said: “We are very disappointed by this additional delay.

“There is still substantial work to be accomplished in the OL3 EPR project and it is essential that all the necessary technical, human and financial resources are allocated to the project. The restructuring of the French nuclear industry must not compromise this.”

The consortium plans to make grid connection for the reactor in December 2018 followed by regular electricity production in May 2019.

Silvennoinen added: “Our objective remains the prompt completion of the OL3 EPR project. TVO continues to be committed to supporting the turn-key plant supplier.”

Areva is responsible for the overall project coordination and the functional and technical integration of the complete plant while Siemens is responsible for Complete Turbine Island (TI).