Update on the Flamanville EPR

December 16, 2022

Update on the Flamanville EPR EDF adjusts the schedule for the Flamanville 3 project: the nuclear fuel loading is now scheduled for the 1st quarter of 20241. The estimated cost at completion changes from 12.7 billion euros to 13.2 billion euros2. This schedule update is mainly due to supplementary studies that were needed to establish a new process for the stress-relieving heat treatment (SRHT)* of some welds that have been upgraded in the last two years, which are located close to sensitive equipment for the nuclear plant functioning. The teams have now moved on to the final stage of the stress-relieving heat treatment of the upgraded welds and to the stage of closing the main secondary circuit. After the nuclear fuel loading, the start-up operations will continue, including notably inspections of all the reactor safety systems, equipment testing and qualification all the way through the temperature and pressure increases of the nuclear steam supply system, and then during the reactor ramping up. At 25% of nominal power, the reactor will be connected to the national electricity grid. The last few months have seen further strategic achievements in the pre-operation phase of the Flamanville EPR, highlighting the strong commitment of industry stakeholders: The complex work of upgrading the main secondary circuit penetration welds is completed, and all the welds have been deemed compliant with break preclusion concept. These first of their kind operations were achieved using remotely operated equipment and required more than twelve months of analyses and qualification prior to implementation at Flamanville.System performance testing of electrical equipment and fuel loading operations have been completed and deemed compliant with requirements. * Stress-relieving heat treatment (SRHT) is a process carried out after welding to relieve residual welding stresses and achieve the right mechanical characteristics for the welded part. This press release is certified. Check its authenticity on About EDF As a major player in energy transition, the EDF Group is an integrated energy company active in all businesses: generation, transmission, distribution, energy trading, energy sales and energy services. EDF group is a world leader in low-carbon energy, having developed a diverse production mix based mainly on nuclear and renewable energy (including hydropower). It is also investing in new technologies to support energy transition. EDF’s raison d’être is to build a net zero energy future with electricity and innovative solutions and services, to help save the planet and drive well-being and economic development. The Group is involved in supplying energy and services to approximately 38.5 million customers (1), of whom 29.3 million in France (2). It generated consolidated sales of €84.5 billion in 2021. EDF is listed on the Paris Stock Exchange. (1) Since 2018, customers are counted per delivery site. A customer can have two delivery points: one for electricity and another one for gas. (2) Including ÉS (Électricité de Strasbourg) and SEI. 1 See EDF’s press release of 12 January 20222 In 2015 euros and excluding interim interest

PR_EDF_Update on the Flamanville EPR

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