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By Bate Felix
PARIS, Sept 28 (Reuters) - French state-controlled utility EDF said on Wednesday it would carry out more tests on 12 nuclear reactors during their planned outages in the coming months, which could affect the length of the outage period for some of the reactors.
French year-ahead electricity prices, rose alongside European forward power contracts to hit one-year highs on Wednesday on fears of tight French nuclear supply in the months ahead.
“In 2015, we discovered the phenomenon of carbon segregation in the Flamanville EPR reactor. We decided to verify other equipment in the French nuclear park to make sure that other components are not impacted by the phenomenon,” the spokesman told Reuters.
“There are outages that could take longer than planned during the tests,” the spokesman said.
EDF said last week that as a result of the planned outages, it was revising its 2016 nuclear output target from 395-400 terrawatt hour (TWh) to 380-390 TWh, and 2017 nuclear output in the range of 390-400 TWh. (nFWN1BX0N3)
The spokesman said the company had already factored in the outages when it gave its revised nuclear output target.
He said the tests were not related to another ongoing probe into manufacturing tracking records of equipment for nuclear power plants from Areva’s Creusot plant.
EDF will have to provide complimentary information following tests as requested by French nuclear safety authority ASN in June, the spokesman said.
ASN said in June that certain steam generator channel heads at the reactors could contain a zone comprising a high carbon concentration, which could weaken the mechanical resilience of the steel and its ability to resist the spreading of cracks.
The regulator said on its website in June it had asked EDF to demonstrate the mechanical strength in these channel heads, some of which were made in Japan.
The reactors affected include Bugey 4; Civaux 1; Dampierre 3; Fessenheim 1 and 2; Gravelines 2 and 4; St Laurent 1 and Tricastin 1, 2, 3 and 4.
EDF’s spokesman said some tests were carried out during planned outages in the summer and those reactors have resumed production except for the remaining 12.
“These 12 reactors have components that were forged in Japan and we have to carry out supplementary tests on them. Obviously, this could have an impact on the outage but we have taken this into account when we gave a revised output target for the year and next year,” he said. (Reporting by Bate Felix; Editing by Geert De Clercq and Jane Merriman)