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By Bate Felix
PARIS, Oct 13 (Reuters) - The chief executive of French utility EDF said he hoped more offline nuclear reactors could return to production before the end of the year, following reports that France could face tight supplies this winter.
"We are working to make sure reactors that are on outage resume production," Jean-Bernard Levy told reporters on Thursday.
"We are still carrying out demonstrations with ASN and we hope that some of these reactors will resume production by the end of the year," he said.
French nuclear safety watchdog ASN has asked EDF to test 12 reactors which could contain zones with high carbon concentration in their steam generator channel heads, which it said could weaken their resilience.
Power prices have spiked sharply higher in recent weeks on fears of supply shortages.
Currently, 20 out of 58 French nuclear reactors are shut down for planned or statutory maintenance for various time periods ranging from a couple of days to several weeks, while a couple more are at reduced capacity.
As a result, about 34 percent of French nuclear capacity is offline.
"It is true that we have more reactors that are offline than what we are used to during this time of the year," Levy said.
"It is our duty to continue to provide French homes with all the electricity they need."
He said France, a net exporter of electricity on an annualised basis, has increased imports in recent days as demand rose amid cold weather. (Reporting by Bate Felix; Writing by Michel Rose; Editing by Geert De Clercq and Susan Fenton)