On 2 June 2020, ASN asked EDF to conduct fresh survey inspections of the main primary circuit in the “break preclusion” scope. EDF established a representative sample of welds for which additional X-ray inspections were performed between February 2021 and the second half of 2021, with satisfactory results. The ASN requested that this programme of additional X-ray inspections be supplemented by ultrasound inspections. These re-inspections were carried out on the sample and proved satisfactory.
In a separate development, on 2 March 2021 EDF declared a significant event to ASN. This concerned the incomplete consideration of the 2006 study referential in respect of the implantation of three nozzles (1) on the main primary circuit.
Three scenarios were investigated by EDF and Framatome in the first half of 2021 at the request of the ASN. On 21 June 2021, EDF submitted a file to the ASN stating that it had chosen the solution consisting of installing a “retaining clamp” on each of the nozzles concerned. In a letter dated 8 October 2021, the ASN indicated that it had no objection in principle to this solution, although the design file for the retaining clamps would be examined by IRSN.
The ASN also stressed the need to demonstrate the quality of welds with respect to the requirements applicable to pressurised nuclear equipment. The X-ray inspections carried out between August and October confirmed that these welds are of good quality. These inspections must be supplemented by ultrasound inspections, for which the process and implementation schedule are currently being established.
The Flamanville EPR is equipped with a recirculation system for the water in the main primary circuit in the event of a pipe breach. In the event of an accident, this system recovers water from the bottom of the reactor building and recirculates it into the tank in order to cool the fuel assemblies.
A problem was detected during a “full-loop” test in the summer of 2021: the debris contained in the recirculated water was not effectively filtered by the filters located at the bottom of the reactor building.
To date, EDF has identified solutions to improve the efficiency of the filters and resolve this problem. EDF has presented the scope of these solutions to the ASN in a file submitted at the end of December 2021. Its investigation is underway.
Following the discovery of corrosion on the pressuriser valves (PSRV valves) of the Olkiluoto EPR (Finland), EDF and Framatome carried out inspections on this equipment and also discovered traces of corrosion on the valves of the Flamanville EPR. EDF and Framatome have decided to take it into account and to modify the material used for certain valve pilot components. Several corrosion resistance tests were performed in order to select the best material. These components are being manufactured and will be installed at the site in the first half of 2022. In addition to dealing with this difficulty, the ASN is continuing to investigate the operation and reliability of the pressuriser valves.
EDF has analysed the potential impact of the technical issues encountered on reactor 1 of the Taishan plant (see section 1.4.5.3.6.1 “Activities in China”)(3) on the commissioning of the Flamanville EPR. Inspections carried out on the relevant fuel assemblies showed mechanical wear of certain assembly components, a phenomenon that has already been encountered in several reactors in the French nuclear fleet. In the perspective of the commissioning of Flamanville 3, a solution will be instructed with the ASN in order to carry out the potential necessary modifications.
In its press release of 9 October 2019 (4), EDF specified that the provisional schedule for implementing the preferred scenario for repairing the penetration welds, subject to the date on which the ASN would approve this scenario, would mean the fuel being loaded at the end of 2022, and a revised construction cost of €12.4 billion(5) excluding interim interest.
In its press release of 12 January 2022 (6), EDF updated these elements, taking into account the impact of the health crisis on the activities of the Flamanville EPR, the state of progress of operations to upgrade the welds of the main secondary circuit and the preparation of the commissioning of the facility. The fuel loading date has been shifted to the second quarter of 2023 and the estimated completion cost has been increased from €12.4 to €12.7 billion (7) excluding interim interest.
The additional costs relative to the October 2019 estimate were increased to €20151.8 billion and have been recognised primarily in “other operating income and expenses (8)” rather than as investments. For 2021, these additional costs booked as “other income and expenses” amounted to €573 million. The amount of interim interest as shown in the financial statements at the end of December 2021 amounts to €3,471 million.
The costs of post-commissioning modifications are not included in the construction cost of the project.
The project no longer has any margins, either in terms of its schedule or in terms of costs at completion. As works progress, new technical issues emerge and may increase the risk of a postponement and of budget overrun regarding the cost incompletion. In addition, worksite delays entail a risk of equipment and materials ageing. Other risks may also emerge. The risk regarding the schedule and completion cost is therefore very high (see section 2.2.4 “Operational Performance-related risks” – risk factors 4A “Management of large and complex industrial projects (including EPR projects)”).
On 15 April 2016, EDF submitted a safety options file for the “New Model EPR”(NM EPR) project to the French Nuclear Safety Authority.
In early 2018, the permanent experts’ group for nuclear reactors submitted its conclusions on the safety options file. In particular, it found that “most changes in the design used for the NM EPR project take into account the lessons learned from the feedback on Flamanville EPR and on the reactors currently operating as well as lessons learned from the accident at Fukushima Daiichi,” and “is of the opinion that the design options used for the NM EPR project, complemented or modified in the light of the discussions held during the technical examination which have led to a number of commitments, are likely to ensure a safety level at least equivalent to that of the Flamanville 3 EPR reactor and complies with the recommendations of ASN Guide no. 22 (on the design of Pressurised Water Reactors).”
In its opinion no. 2019-AV-0329 of 16 July 2019 relative to the safety options file, the French Nuclear Safety Authority “considers that the safety handbook adopted for the planned NM EPR reactor is on the whole satisfactory, in particular as regards legislation, the guide dated 18 July 2017 […] and international recommendations”.
Furthermore, the work undertaken by EDF and Framatome on the New Model EPR project led to the finalising in 2017 of the technical configuration of a model named EPR 2 which could replace the nuclear fleet currently operating in France and ultimately expand the French nuclear industry’s export offers. EPR 2 is an optimised version of the EPR, following on from the EPR in industrial terms whilst integrating feedback from EPR worksites and power plants currently in operation.
As of this date, EDF informed the ASN of the new configuration. In the same opinion as the one on NM EPR, the ASN deemed that the findings relating to NM EPR would also apply to EPR 2.
(1) A nozzle allows to connect auxiliary circuits to the primary circuit.
(2) SIS = Safety injection system (used to add pressurised borated water to the reactor’s primary circuit in the event of an accident that causes a major breach to this circuit). CHR = Containment Heat Removal system for the reactor building in the event of a severe accident (with core meltdown).
(3) See EDF's press release of 12 January 2022 "Update on the Flamanville EPR".
(4) See EDF’s press release of 9 October 2019, “Flamanville EPR: EDF favours a scenario to rework the penetration welds on the main secondary circuit using robots and adjusts the schedule and construction cost estimation”.
(5) In 2015 euros, excluding interim interest.
(6) See EDF’s press release of 12 January 2022 “Update on the Flamanville EPR”.
(7) In 2015 euros. This estimate takes into account the analytical allocation of a portion of the compensation paid by AREVA (for €225 million) under the settlement agreement EDF and AREVA reached on 29 June 2021 to the dispute over the defective welds in the main secondary circuit.
(8) IAS 16 paragraph 22 on abnormal costs incurred in connection with assets constructed by the Company. These costs will affect the years 2020, 2021, and 2022.
