The new research reactor will play a central role in a new nuclear research and human resource development that utilizes the Monju site, and is expected to contribute to various innovative activities.

In Japan, more than 20 research reactors have been in operation by the government, universities and private companies. However, in recent years, many reactors have been decommissioned, and the number of reactors in operation is decreasing and aging is progressed.

On the other hand, research and analysis using neutrons is a field that continues to glow up both academically and industrially. The number of users of the Japan Proton Accelerator Research Complex (J-PARC) and research reactor JRR-3 continues to increase, and it is necessary to maintain and improve the research infrastructure to meet the demand for neutron applications.

In addition, Japan is aiming to become carbon neutral by 2050, and it would be desirable to restart nuclear power plants on the premise of ensuring safety. In order to operate nuclear reactors safely, it is essential to develop human resources who can steadily perform the decommissioning of nuclear facilities, as well as the technology for operating nuclear reactors.

The new research reactor is expected to contribute to a wide range of basic research, applied research, and industrial use through the R&Ds on particle beams (neutrons) and radioisotope application, as well as to a continuous development of human resources.

The new research reactor is a unique one in which the local community and industries are involved from the planning phase. From a global point of view, the facility will be positioned as an "international public property" contributing to the solution of global issues.

As a government decided in December 2016,

“In the future, a new research reactor will be set up in the “Monju” site, and is positioned as a core base to support Japan’s future nuclear research and human resource development.”

The Ministry of Education, Culture, Sports, Science and Technology (MEXT) started research on a new research reactor from 2017. From 2019, MEXT solicited proposals for a "conceptual design of a new test and research reactor to be installed at the Monju site and a review of its operation". JAEA, Kyoto University and University of Fukui were adopted as the core institutions of the entrusted business to carry out conceptual design and application of the reactor (FY2020-2022). JAEA is the representative organization of the core institutions.