PARIS, July 7 (Reuters) - French utility EDF has postponed by three months the restart of its 900 megawatts (MW) Fessenheim 2 nuclear reactor to Jan. 31 2018 because a safety assessment of a steam generator was taking longer that expected.
Fessemheim 2 was shut down in June, 2016, after French nuclear watchdog ASN suspended the generator's test certificate following Areva's detection of irregularities in the manufacturing process at its Creusot unit.
ASN then launched an investigation into where the potentially defective parts ended up and whether they were in use and were safe.
EDF said in a note on its website that ASN's analysis of the steam generator was ongoing. An EDF spokeswoman said the new restart date was updated after the firm received some visibility from the watchdog.
The two reactors at Fessenheim, France's oldest nuclear power generation plant, have a combined capacity of 1,800 MW. They have been earmarked for complete shutdown once EDF's new generation EPR reactor under construction in Flamanville is operational.
France's previous government signed a decree in April that said Fessenheim will stop electricity production by April 2020 as a first step of cutting the share of atomic power in its electricity mix to 50 percent by 2025 from over 75 percent now. (Reporting by Bate Felix; editing by Richard Lough)