Safety of GFR through innovative materials, technologies and processes


Nuclear energy constitutes a significant part of the energy market in Europe. The long term plans predict also further development of the nuclear reactor fleet as a part of well balanced energy mix in France, Great Britain and the Visegrad countries (Poland, Czech Republic, Slovakia and Hungary). Among advanced nuclear systems, ESNII - the European Sustainable Nuclear Industrial Initiative of SNETP, gives a high priority to innovative Fast Neutron Reactors with a closed fuel cycle, for sustainable low-carbon energy production in Europe.i Three technologies have been selected by ESNII: The sodium-cooled fast neutron reactor (SFR), the gas-cooled fast neutron reactor (GFR) and the lead-cooled fast neutron reactor (LFR).

The future European fast neutron reactors require significant R&D, technology breakthrough and innovation needed to achieve safety and security standards anticipated at the time of their deployment. ii  Directive 2014/87/Euratom establishing a Community framework for the nuclear safety of nuclear installations requires that new nuclear reactors (and in particular future Generation- IV reactors) are designed to avoid large radioactive releases that would require protective measures that could not be limited in area or time (Art. 8a).

Extensive research and development of GFRs are still needed in various fields and areas to achieve this unprecedented level of safety in fast reactors. Since there has not been any GFR reactor ever built, most of the effort has been dedicated to development of a demonstration unit of this technology called ALLEGRO. An overview of the current concept of the demonstrator is depicted in Figure 1.

The SafeG project combines high-level research of common aspects of all GFRs, such as thermal-hydraulics phenomena influencing decay heat removal, ways of passive and diversified shutdown of the reactor, and proliferation resistance, with safety research and development targeted specifically to the ALLEGRO demonstrator. This combination is the most effective way how to increase the technology readiness level of the GFR technology.

The SafeG project’s approach is based on long-term and extensive experience of the project consortium partners in nuclear R&D, development and application of various simulation tools, licensing of nuclear installations, material science, and in reactor safety in general. The outcomes of the preceding phases of the ALLEGRO development will be used, especially the outcomes of the GoFastR projectiii, aimed at the development of the advanced GFR system through its viability phase, and the VINCO projectiv focused on establishing a cooperation network in Visegrad Group and France represented by the "V4G4 Centre of Excellence" dedicated to studies of gas-cooled reactor technology, mainly Gas-cooled Fast Reactors (GFR). It is worth pointing out that the SafeG concept is closely related to the activities of NOMATEN Centre of Excellence, a joint NCBJ-CEA–VTT project.