Current status of HTGR development in Japan

日本における高温ガス炉開発の現状

西原 哲夫 

Nishihara, Tetsuo

High Temperature Gas-cooled Reactor (HTGR) has can supply high temperature heat of above 900C which makes possible to use nuclear energy not only for power generation but also for heat source of various industries, such as hydrogen production. Japan Atomic Energy Agency (JAEA) promotes the research and development of HTGR by using High Temperature engineering Test Reactor (HTTR) which is the first HTGR in Japan. HTTR had stopped operation after the Great East Japan Earthquake in 2011. JAEA got permission of changes to reactor installation in conformity to new regulatory requirements from Nuclear Regulation Authority in 2020. HTTR restarted operation in 2021. Loss of forced cooling test to demonstrate the inherent safety feature of HTGR resumed in 2022. Japanese Government started NEXIP initiative since 2020 to develop various types of nuclear reactor technologies. Two companies carried out design of commercial HTGR system. Furthermore, many countries are developing HTGR system under national project. China constructed demonstration reactor and achieved first criticality in 2021. USA and UK promote HTGR deployment program. Green growth strategy decided by Japanese government in which hydrogen production using HTGR is recommended. JAEA starts HTTR heat application test project to establish s safety design for coupling hydrogen production plant to nuclear plant and to demonstrate hydrogen production by nuclear heat.