On Friday 4 November 2022, the Cattenom nuclear power plant (CNPE), operated by Electricité de France (EDF), announced that the Nuclear Safety Authority (Autorité de sûreté nucléaire - ASN) after weeks of discussion, expert appraisals and the performance of additional checks on CNPE reactor no. 1, considers that the two welds concerned must be repaired before restarting the reactor.
With regard to the other welds showing indications of weaker dimensions and whose mechanical strength has been justified, ASN considers that these can be maintained as they are for a limited period.
EDF has taken note of the request from the Nuclear Safety Authority to carry out, during the current outage of CNPE reactor no. 1, the repairs of two welds of the safety injection circuit (RIS) on which indications of stress corrosion cracking (corrosion sous contrainte - CSC) have been detected . The site must now organise the implementation of this work, the precise scope of which will be established in the coming days in connection with the schedules and the mobilisation of the resources necessary to carry out the operations. The forecast duration of CNPE reactor no. 1 outage was adapted accordingly and redeclared to the system operator in accordance with the REMIT process, on 26 February 2023.
The continuation of checks and the evolution of intervention schedules also lead to an update of the shutdown duration dates for reactor units no. 3 and no. 4:
CNPE reactor no. 3: announced return on 26 February 2023
The CSC checks and expertise are continuing: at the beginning of the week, the teams from the Cattenom plant finalised the cutting work with the complete removal of the half lines of the RIS circuit. These last samples will be sent to the LIDEC laboratory based in Chinon for metallurgical expertise. From mid-November, CNPE teams will proceed with the reassembly and welding phase of the new elbows on the installations.
CNPE reactor no. 4: announced return on 21 November 2022
On the evening of Wednesday 2 November 2022, the teams finalised the operations to reload new fuel into the reactor vessel. Over the next few weeks, CNPE will be carrying out the activities prior to restarting the reactor in complete safety (equipment tests and qualifications, etc.).
EDF adjusts its nuclear production estimate for 2022 to 275-285 TWh against 280-300 TWh previously. This estimate takes into account the extension of the outage period of four EDF nuclear reactors concerned by the programme of checks and repairs of the CSC phenomenon, including those of Cattenom reactor units no. 1 and no. 3.
Estimates of nuclear production in France for 2023 and 2024, respectively 300-330 TWh and 315-345 TWh, remain unchanged.
