The non-recurring additional costs resulting from the necessary repairs to the main secondary circuit welds (see Group press release of 9 October 2019) are recorded in other income and expenses at the amount of €573 million in 2021 (€397 million in 2020) (see note 7). Additional costs induced by the readjustment announced on 12 January 2022 will be recognised in other operating income and expenses;
The balance of property, plant and equipment in progress (excluding assets operated under concessions), i.e. €11,131 million, principally concerns EDF SA’s existing nuclear plants (70%) in line with the Grand Carénage programme (replacement of major components, particularly steam generators; work in connection with periodic reviews and 10-year inspections), and to a lesser extent (around 15%) EDF Renewables (power plants in development in Europe, North America and emerging countries).
Property, plant and equipment in progress increased by €5,760 million as the level of investment in 2021 is significantly higher than the amount of assets brought into service during the year (see note 10.3).
Since 2014 EDF has been implementing its Grand Carénage industrial refurbishment programme designed to enhance reactor safety and extend nuclear fleet operating lifetimes beyond 40 years. The most recent estimate of the programme’s cost for the period 2014 to 2025 was established in 29 October 2020 and amounted to €49.4 billion in current euros.
This cost estimate mainly reflected the first information about the additional works to be conducted, based on the fourth periodic review of the Group’s 900MW reactors, a process that concluded with the ASN’s decision issued on 23 February 2021. The work required covers studies, modification work and initially unplanned additional equipment to improve safety levels. This estimate also factored in the revised duration of scheduled maintenance outages for 10-year and partial inspections, building on prior year experience, and the impacts of the Covid-19 pandemic for the period 2020-2022 as estimated in 2020. The estimated cost of the Grand Carénage programme is regularly updated, and currently stands at €50.2 billion in current euros. This figure takes account of further work, studies and controls to be conducted, and a revaluation of certain costs. The industrial work will continue beyond 2025, and consequently the investment expenses will remain high beyond that date.
The principal events and industrial milestones of the Grand Carénage programme in 2021 were the following:
The main developments at the Flamanville site in 2020 were the following:
The second hot functional test phase which started on 21 September 2019 was completed in February 2020. Hot functional testing checks plant performance under simulated normal operating conditions.
In the context of the Covid-19 pandemic, after a cluster of cases was identified in the Manche area, work on the Flamanville site was restricted to safety, security and environment monitoring work only from mid-March (see note 1.4.3). General activity on the site resumed progressively from 4 May 2020 and was back to near-normal levels in July 2020.
Functional tests of the open reactor vessel were successfully completed between 21 May and 25 June 2020.
Following the ASN’s decision of 8 October 2020 authorising partial commissioning of the EPR, the first fuel assemblies arrived at the site on 26 October and are stored in the reactor building pool.
In parallel, the upgrading work continued on non-penetration welds on the main secondary circuit that had quality deviations or did not meet the break preclusion requirements defined by EDF, and several welds were repaired in August 2020 once the ASN issued its first authorisations. EDF also decided to include the welds on the circuit supplying water to the steam generators in the scope of the repairs concerning the main secondary circuit. Qualification of the repair procedure for these welds began, with the objective of performing the work in the second half of 2021. At this stage, the repairs concern a hundred welds in the secondary circuits.
A review was conducted in 2020 of the impact of France’s first national lockdown on the Flamanville project. This did not lead to any change to the fuel loading dates or the construction cost announced in October 2019, but it showed that the project has no remaining margin in its schedule or cost. However, achievement of the targets depends on a number of factors, notably the ASN’s examinations of EDF’s proposed methods for repairing the main secondary circuit welds, particularly the qualification of welding robots for repairing the penetration welds.
Work on these repairs could not begin until the ASN made its final decision as to approval of the entire process involving remote-controlled robots, which was deferred to the first quarter of 2021. This phase of the project is among those in the critical path for on-schedule finalisation of the EPR.
The fuel assemblies required for the first fuel load continued to arrive during the first half of the year, and the entire first core is now stored in the Flamanville 3 reactor building pool.
The process of repairing the penetration welds on the main secondary circuit using remote-controlled robots was approved by the ASN on 19 March 2021, several weeks behind the expected date, and work began on the eight welds that were not compliant with the break preclusion principle. All eight were repaired in 2021, then subjected to stress-relieving heat treatment. Demonstration of the qualification of the stress-relieving heat treatment for repairs of VVP (steam discharge pipework circuit) penetration welds was validated by the ASN, which issued authorisation for its use in late 2021. Furthermore, four ARE (steam generator water supply circuit) penetration welds also require repair, and qualification of the repair process is under way at the ASN. This process is an adaptation of the process used for VVP penetration weld repairs.
For the non-penetration welds located on the main secondary circuit that had quality deviations (this concerns 45 VVP welds and 32 ARE welds), the ASN issued approval in April 2021 for the repair of a third batch of 6 welds. In the 3 batches authorised to date, 12 weld upgrades have been completed. In April the ASN gave approval for the related regulatory checks, which are currently in process.
In total, a hundred welds (penetration and non-penetration) on the main secondary circuit are concerned by repairs to the VVP and ARE pipework. The final stage of repair for most of these welds will be an optimised stress-relieving heat treatment, prior to the final verification. Repairing these welds remains one of the key challenges on the Flamanville 3 critical pathway.
On 2 March 2021 EDF declared a significant event to the ASN, concerning incomplete application of the 2006 design standards when installing three nozzles on the main primary circuit (these nozzles connect auxiliary circuits to the primary circuit). At the request of the ASN, three scenarios were examined by the Group’s engineering teams. A file was sent to the ASN on 21 June 2021, stating that EDF’s chosen solution is to install a “containment collar”, and asking the ASN for its position on this solution, so that all the design and procurement activities could be launched by the end of 2021. In a letter of 8 October 2021 the ASN indicated that it had no objections to this solution in principle. Nonetheless the design file for the containment collar will be examined by the French Radiation protection and Nuclear Safety Institute IRSN (Institut de radioprotection et de sûreté nucléaire).
