The French Nuward modular reactor project, led by Électricité de France (EDF), has reached a regulatory milestone with the completion of the second phase of a joint assessment conducted by six European nuclear safety authorities. The process, coordinated by the Autorité de Sûreté Nucléaire (ASN), aimed to evaluate the compatibility of the Nuward design with national regulations and international safety standards.
Enhanced cooperation among six European countries
Initially launched in 2022, the review involved three authorities: Finland’s Radiation and Nuclear Safety Authority (STUK), the Czech Republic’s State Office for Nuclear Safety (SÚJB), and France’s ASN. A second phase was initiated in 2023 with the addition of three more regulators: Poland’s National Atomic Energy Agency (PAA), Sweden’s Radiation Safety Authority (SSM), and the Netherlands’ Authority for Nuclear Safety and Radiation Protection (ANVS).
This second phase expanded the scope of the assessment to cover additional technical topics, including management of extended design conditions, containment and radiological impact assessments, and the architecture of control and electrical systems. The methodology involved structured dialogue between regulators and the reactor’s designer.
A tool to anticipate regulatory divergence
According to the final report published on 2 December, the joint approach allowed technical discrepancies to be identified early in the development process, reducing the risk of delays during national certification procedures. Most differences identified stemmed from interpretation and implementation of requirements rather than from the requirements themselves.
Regulators described the initiative as a tool to improve efficiency in information sharing and to support revision of national regulatory frameworks. The overarching goal is to enable more streamlined joint evaluation of future small modular reactor (SMR) projects across Europe.
Strategic adjustments for Nuward
Alongside the regulatory work, EDF announced in July 2024 a design optimisation in response to feedback from European industrial stakeholders. The revised focus is on using proven technologies to ensure project deadlines and cost targets are met.
The updated Nuward concept is based on a 400 MW reactor, with an optional cogeneration capacity of up to 100 MWt. The final design is expected by mid-2026. EDF plans to begin construction in France in 2030, with the first unit projected to take approximately three years to build.
