French nuclear operator EDF has further delayed the restart of several of its nuclear reactors affected by stress corrosion, in some cases until as late as June, as it struggles to get enough units online to meet winter power demand.

EDF has faced an unprecedented number of outages at reactors this year due to a delayed maintenance schedule and stress corrosion, reducing nuclear output to 30-year lows just as Russia's war in Ukraine hit Europe's energy supplies.

The restart of the 1.3 gigawatt (GW) Penly 2 reactor was delayed four and a half months to June 11, according to a revised scheduled published over the weekend.

EDF said it had sent a letter about a new repair strategy for its 1.3 GW reactors to the Nuclear Safety Authority (ASN) and is aiming to deal with all those affected by the end of 2023.

Previous repairs on the Penly 1 reactor took five months.

The 1.3 GW Golfech 1 reactor was similarly delayed until June 11 from a scheduled restart date of Feb. 18.

The 1.3 GW Cattenom 3 reactor restart was postponed one month to March 26, and the 1.5 GW Civaux 2 also delayed one month to Feb. 19 despite EDF confirming that stress corrosion repairs there had been completed.

However, the restart of the 1.3 GW Cattenom 1 reactor was moved forward by two weeks to Feb. 12.

(Reporting by Forrest Crellin, Benajmin Mallet and Tassilo Hummel Editing by David Goodman, Kirsten Donovan)