US, Japanese firms agree to cooperate on fast reactors

JAEA said Japan aims to accelerate innovations in various nuclear technologies in collaboration with the development of next-generation innovative reactors overseas. "As part of this, with the support of the US Department of Energy (DOE), the United States, which is trying to lead the world by starting the development of a fourth generation reactor including a sodium-cooled fast reactor under its Advanced Reactor Demonstration Program (ARDP), we are trying to promote fast reactor development cooperation."

"A Memorandum of Understanding regarding TerraPower's cooperation in the development of Natrium is the first step of cooperation in the development of sodium-cooled fast reactor technology in Japan and the United States," it added. "In the future, through cooperation with TerraPower, we would like to develop cooperation in the development of fast reactors between Japan and the United States, and to maintain and improve our technological capabilities related to the development of fast reactors."

JAEA has a history of operating sodium-cooled fast reactors, such as Monju in Fukui Prefecture and the Joyo experimental fast reactor in Ibaraki Prefecture. However, the development of fast reactors in Japan has been halted since the government decided to decommission Monju in 2016, following a series of problems, including leakage of sodium coolant in 1995.

"Focusing on manufacturing technology, JAEA, MHI, MFBR and TerraPower have exchanged information on each other's technologies, as well as technologies unique to sodium-cooled reactors, including refueling machines and damaged fuel detection systems," JAEA said.

TerraPower, it said, has acquired the know-how and test facilities of JAEA related to fast reactors obtained through Joyo, Monju and the Japan Sodium-cooled Fast Reactor concept for the next-generation fast reactor, etc., and equipment design of Japanese companies in order to start the operation of Natrium.

"As a Japanese industry, we will utilise the knowledge of Hitachi-GE Nuclear Energy, Toshiba Energy Systems, Fuji Electric, etc. involved in the construction of Joyo and Monju, and consider participating in cooperation," JAEA added.

TerraPower has been selected by DOE to receive cost-shared funding through the ARDP programme to test, licence and build an advanced reactor within the next seven years.

The company has selected Kemmerer in Wyoming as the preferred site for the Natrium nuclear power plant demonstration project, which will feature a 345 MWe sodium-cooled fast reactor with a molten salt-based energy storage system. The storage technology can temporarily boost the system's output to 500 MWe when needed, enabling the plant to follow daily electric load changes and integrate seamlessly with fluctuating renewable resources.