June 10, 2026

JAEA signs the Memorandum of Cooperation
with the National Nuclear Center of the Republic of Kazakhstan (NNC RK)
on a cooperative research project concerning demonstration fast reactors

The Director General of the NNC RK, Professor Erlan BATYRBEKOV, and the President of the Japan Atomic Energy Agency (JAEA), Mr. Masanori KOGUCHI, signed a Memorandum of Cooperation in Almaty, Kazakhstan, on June 3rd, 2026. The memorandum concerns the cooperative research project, EAGLE-4, which focuses on severe accident mitigation measures for demonstration fast reactors with the aim of enhancing the safety of fast reactors, one of the next generation innovative reactor systems.

(Note) Severe accident: An accident that far exceeds the design basis of the nuclear facility and leads to a severe state involving core meltdown or the like.

JAEA and NNC RK have been advancing the phased “EAGLE Projects” on core safety experiments of fast reactors for over 20 years since the early 2000s and implemented three phases: EAGLE-1, EAGLE-2, and EAGLE-3.
Through experiments using the research reactor “IGR” owned by NNC RK, this series of projects aiming to demonstrate the safety of fast reactors confirmed that molten fuel is promptly discharged from the core in the event of a severe accident, thereby preventing further progression of the accident.

JAEA and NNC RK have agreed to undertake a fourth-phase cooperative research project following the EAGLE-3 project, and to promote core safety experiments toward the social implementation of fast reactors while further strengthening collaboration between both institutions.

In this cooperative research project, core safety experiments will be conducted using NNC RK’s experimental facilities, including the IGR, which is the sole experimental reactor in the world capable of achieving fuel melting at the fuel assembly scale.

The aim of these experiments is to obtain data and knowledge that support the effectiveness of the molten fuel discharge mechanism being developed for demonstration fast reactors as a severe accident mitigation measure.

JAEA will conclude in coming months an Implementation Arrangement that defines the detailed specifications of the core safety tests to be implemented under the EAGLE-4 Project and will proceed with the cooperative research with NNC RK.

○JAEA’s initiative in the development of fast reactors
Based on the “Strategic Roadmap” decided by the Ministerial Meeting on Nuclear Energy (December 21st, 2018, revised December 23rd of 2022) which outlines the Japanese government’s approach to fast reactor development, a demonstration fast reactor is planned to operate by 2050.

In collaboration with domestic companies, JAEA is conducting research and development towards the social implementation of fast reactors, including the conceptual design of a demonstration fast reactor and the development of severe accident mitigation technologies.

Overview of the Experiment Using the IGR within the EAGLE Project