For more information

• Read the publication "Euratom research in action and opportunities for Europe
• Read the Commission's statement on EU Small Modular Reactors (SMR) to 2030: research and innovation, education and training
• Discover the ongoing SMR projects co-financed by the Euratom programme

In view of the renewed interest and initiatives in nuclear energy in numerous countries in Europe and around the world, the members of the European Technical Safety Organisations Network (ETSON) – a grouping of 17 EU TSOs and their associated members in Japan, Ukraine and the United Kingdom – have started a network-wide reflection on its future strategy. The principles that will guide are:

• We firmly believe that maintaining and developing the highest level of nuclear safety in current and new projects, as well as efficient, reliable and trusted nuclear safety systems and organisations is of paramount importance. To this endeavor, TSOs actively contribute to the reliability of the global system through the technical safety expertise they provide to Regulators and National Authorities.
• As per the requirements of the IAEA, all regulatory functions should be performed based on technical and scientific work independently performed. The maintenance of expertise supporting the RB’s functions and the arrangements between the RB and its support organisations are identified as key pillars of the framework for safety and under the direct responsibility of the governement The availability of and access to dedicated safety research for maintaining and developing further technical expertise is underlined. To this end, ETSON members believe that safety research and the provision of safety-related expertise have to be strongly connected to allow for their mutual advancement.
• Furthermore, TSOs and the independent science based expertise they provide for, can actively and efficiently contribute to the dialogue with the Public on all nuclear energy related topics, which has been highlighted as a top priority at the recent IAEA Regulatory Conference from February 13th to 15th in Abu Dhabi and will be further developed during the coming IAEA TSO Conference to take place in 2024, which will allow for in depth discussions on safety expertise and research, with all stakeholder

Download the Statement of the ETSON board (PDF)

A delegation from the National University of Singapore (NUS)/Singapore Nuclear Research and Safety Initiative (SNRSI) led by Professor Pao Chuen LUI, Chairman of SNRSI and SNRSI Director Keng Yeow CHUNG and from the Energy Market Authority led by Director Darryl Kah Inn CHAN visited IRSN's safety and radiation protection research facilities at Cadarache on September 19 and 20, 2022.

The facilities visited were the following: 

• AMANDE​,
• MIRCOM, 
• CABRI model, 
• THEMA, 
• CHROMIA, 
• MAESTRO, 
• ODE, 
• GALAX​IE.

The dele​​gation continued this visit to IRSN Headquarters at Fontenay-aux-Roses on September 23, with a presentation of the research and expertise conducted on atmospheric dispersion models, followed by a presentation of crisis management and the technical Crisis Center.

A final debriefing meeting led by the Director General of IRSN Jean-Christophe NIEL concluded this visit.

The Zaporizhzya nuclear power plant, operated by the Ukrainian staff of Energoatom, has been under the control of Russian forces since March 4, 2022. It has been recently the subject of several bombings, causing great concern about the possible consequences:

• August 5, 2022: bombing of a 330 kV transformer which led to the a​utomatic shutdown of reactor no. 3 and the starting of its emergency generators.
• August 5, 2022: bombing and damage to a nitrogen production station.
• August 6, 2022: bombing near the spent fuel dry storage site.
• August 11, 2022: bombings damaging fire-fighting equipment, a non-radioactive effluent pumping station and radioactivity measurement sensors.
• August 22, 2022: bombing near the thermal power plant causing damage to the electrical interconnection line with the nuclear power plant.
• August 23, 2022: bombing between the nuclear power plant and the neighboring town of Energodar, resulting in fires in the vegetation near the plant.
• August 25, 2022: bombing to the north of the thermal power plant next to the nuclear power plant, resulting in vegetation fires and a temporary disconnection of the nuclear power plant from the electrical grid; emergency diesels would have started.
• August 25, 2022: bombing of an access gallery of reactor no. 2 (link with operating building no. 1), damaging water pipes and electrical links.
• August 28, 2022: bombing of the exploitation building n°1 leading to a perforation of the roof and damages in the present equipment.
• September 1, 2022: bombing of the site leading to the cutting of a 750 kV power line, the shutdown of reactor no. 5 and the starting of the emergency diesels of reactor no. 2.
• ​September 5, 2022: bombing near the thermal power plant which led the operator to cut the last power line connecting the plant to the Ukrainian power grid.

To date, none of these bombings has resulted in radioactive releases at the site. No increase in radioactivity has been detected by the environmental monitoring networks located near the plant. The site teams intervened each time to restore the situation as far as possible. 

In order to facilitate the understanding of the consequences of the recurrent events occurring at the Zaporizhzya nuclear power plant site, this note resituates the plant in its environment, describes the site and recalls the main issues related to its safety in the current context.

Download IRSN information report of September 6​, 2022 (pdf)

On Thursday, August 11, 2022, new shelling was reported in the area of the Zaporizhzhya nuclear power plant in Ukraine. According to the information available, sensitive areas regarding radiological risks were not affected. 

According to Energoatom, the plant's operator, fire-fighting equipment, a non-radioactive effluent pumping station and radioactivity measurement sensors were damaged.

Available measurements in the environment do not show an increase of radioactivity around the site. 

Sensitive areas with regard to radiological risks, particularly in the event of a shelling, are primarily the nuclear reactors and their associated fuel storage pools, the cooling systems used during normal operation or in accident situations and, more generally, areas containing radioactive materials, such as dry storage containers for spent fuel and radioactive effluent storage capacities. 

In this matter, in addition to the equipment and buildings that house them, the external electrical network (330 kV and 750 kV), as well as the supply of water to the plant from the river, are essential for maintaining safety. This is also the case for the fire-fighting equipment. It should be noted that the 330 kV power supply, damaged by a previous shelling on August 5 and 6, 2022, has reportedly been restored. 

In addition, the difficult conditions under which the site is operated (supply capacity for fuel, equipment maintenance, availability of emergency response teams...) (cf. IRSN inform​ation report of March 22, 2022​) may affect the effective status of emergency systems.

Download IRSN information report of August 12​, 2022 (pdf)

On Friday, August 5, 2022, at 2:30 pm, the Zaporizhzhya nuclear power plant in Ukraine was subjected to shelling around a high-voltage 330 kV power line transformer. At that time, 3 reactors were in operation and 3 were shut down. The destruction led to the automatic shutdown of reactor n°3 and the start of its emergency power generators. 

These generators provide power to the reactor's cooling systems in the event of the loss of the plant's external power supply (cf. IRSN information report March 22, 2022​​​). The shelling also caused power outages in the town of Enerhodar, which is close to the plant. 

A little later, on August 5, a second shelling damaged one of the nitrogen-oxygen stations near the radioactive effluent storage buildings. In normal operation, effluents from reactor circuits are treated and stored in liquid or gaseous form to allow their radioactive decay before release into the environment. On the reactors of this plant, nitrogen is used in particular by the gaseous effluent treatment system to inert tanks presenting a risk of hydrogen explosion [1]. In the short term, the supply of nitrogen to the gaseous effluent treatment systems is assured by reserve tanks.

On the evening of Saturday, August 6, 2022, a third shelling took place near the dry spent fuel storage facility, damaging walls, windows, and the roof of the facility, as well as three radiological monitoring sensors. The containers containing spent nuclear fuel assemblies were not damaged.

No radioactive release was observed by the operator on the site following these shelling. The available networks of measurements of radi​oactivity in the environment also showed no increase in radioactivity.

Actions to repair damaged equipment are necessary to restore the plant's lines of defense, especially at its external electrical sources.

Download IRSN information report of August 8​, 2022 (pdf)

[1] Inerting consists in replacing the oxygen in the air with nitrogen.​

IRSN is currently participating in the preliminary review of the safety options for the NUWARD™ project by the French (ASN), Finnish (STUK) and Czech (SUJB) safety authorities with the support of their technical safety organizations (TSO) respective ones, including IRSN for France. 

​​The NUWARD™ project is a concept of electricity production unit, supported by EDF, consisting of two pressurized water nuclear reactors of 170 MWe each. From a safety point of view, this concept has characteristics common to other SMR concepts in development abroad, in particular its low power, its compactness and the implementation of passive safety provisions. For IRSN, SMRs m​ust meet safety requirements at least equivalent to those adopted for third generation reactors, their low power and the inherent safety characteristics put forward by their designers should benefit safety.

IRSN experts have been contributing for nearly ten years to thoughts on the safety requirements and approaches for these new concepts, in particular through their involvement in various international working groups of the IAEA and the SMR Regulators' Forum. [1]

IRSN also participates in several European projects which aim to acquire knowledge on these new concepts, both in support of the safety demonstration and in the validation of simulation tools, for pressurized water reactors but also for other types of reactors, for example high temperature reactors dedicated to cogeneration. 

The evaluation of the performance of passive safety systems being a central element of the safety demonstration of SMRs, a very good understanding of the physical ​phenomena that participate to their activation, their operation and those which can prevent them is necessary. IRSN is considering the development of a specific experimental research platform (PAssive Systems Thermalhydraulic Investigations for Safety) to support its expertise. This new experimental facility will provide knowledge in particular on the operation of a passive core cooling system as well as on the passive cooling of a metal containment immersed in a water pool. ​

For more information : our information memo on Small Modular Reactors​

Notes:

1. The SMR Regulators' forum brings together the safety authorities of France, the United States, Canada, the United Kingdom, Finland, Japan, South Korea, China, Russia, the Czech Republic and South Africa