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PARIS, Jan 13 (Reuters) - EDF is allowed to delay planned outages at two nuclear reactors involved in a safety probe to help the French utility meet demand as a cold snap looms next week, nuclear regulator ASN said on Friday.
EDF had requested delays to outages planned at its Civaux 1 and Tricastin 2 reactors scheduled for this Thursday and Friday, respectively, ASN said.
"This request was motivated by risks to the electricity grid related to the cold snap expected next week," ASN said. "ASN considered this deferral to be acceptable."
Civaux 1 will now go off line for safety checks on Jan. 18 followed by Tricastin 2 on Jan. 26, ASN said.
The agency said it was examining EDF's request to have the Civaux outage delayed until end-March.
A prolonged cold spell is expected to hit France and most of western Europe next week, pushing average temperatures sharply below normal seasonal levels and increasing demand for electricity for heating.
France depends on its 58 nuclear reactors for more than 75 percent of its electricity needs.
ASN said it had authorised EDF to restart nine of 12 reactors whose steam generators were involved in an investigation. The nine represent a capacity of 8.1 gigawatts and seven of them are already back online.
Two others, Bugey 4 and Tricastin 4, will restart on Jan.13 and Jan. 16, respectively.
ASN launched the investigation after raising concerns that steel used in steam generator channel heads could contain high concentrations of carbon which could weaken their ability to resist cracking. (Reporting by Bate Felix; editing by Mathieu Rosemain and Jason Neely)