The IAEA Programme in Support of the Development, Design and Safety Analysis of Innovative Fast Neutron Systems

The International Atomic Energy Agency (IAEA) recognizes the importance of the development and deployment of innovative fast neutron systems to assure the long-term sustainability of nuclear power. In this area the IAEA — with the fundamental support of its Technical Working Group on Fast Reactors (TWG-FR) where all the Member States with a programme on fast neutron systems are represented — acts as the major forum for international cooperation. On the basis of the recommendations provided by the TWG-FR, the IAEA defines and implements multiannual programmes which, in particular, are intended to help Member States in improving their capabilities in the development, design and safety analyses of innovative fast neutron systems. Thanks to the information and experimental data provided by the Member States, the IAEA is in the position to carry out benchmark exercises on different aspects of fast reactors, which contribute to the verification, validation and qualification of the simulation codes to be used for the design and the safety analyses of innovative concepts. Examples of such initiatives are the concluded coordinated research projects (CRPs) on BN-600, Monju and Phenix reactors, the on-going CRP on the EBR-II reactor and the planned CRPs on PFBR, CEFR, BN-800 and Monju reactors. The exchange of information and the collection of technical data within the TWG-FR also allow the IAEA to publish status reports and technical documents, as well as to develop databases with the most up-to-date information on existing and planned fast neutron systems. Furthermore, the IAEA is committed to promote the international harmonization of many aspects of the fast reactor technology. A major example is the development — together with the Generation IV International Forum — of internationally agreed Safety Design Criteria for sodium cooled fast reactors (SFR), which is a major step forward for the licensing of GEN-IV SFR prototypes and industrial demonstrators. Finally, a new CRP on “Sodium properties and safe operation of experimental facilities in support of the development and deployment of Sodium-cooled Fast Reactors (SFR) - NAPRO” has been recently launched in order to harmonize sodium physical and chemical properties to be used in the design of innovative SFRs, and to develop agreed design rules and best practices for sodium experimental facilities, as well as guidelines for the safe handling of sodium. With complementary objectives, the IAEA is also developing a catalogue of existing and planned experimental facilities in support of fast neutron system R&D programmes.