Kansai Electric Power Company is to begin an on-site survey at its Mihama NPP to explore the feasibility of replacing unit 1 with a next-generation advanced reactor. The announcement followed a week of media speculation.
The survey was initially started in 2010 but was halted following the Fukushima Daiichi disaster in 2011. If realised, this will mark Japan’s first new nuclear reactor since Hokkaido Electric Power’s launched unit 3 at its Tomari NPP in 2009.
“We have decided to resume voluntary field surveys,” Kansai said in a statement, adding: “In Japan, where resources are scarce, nuclear power will continue to grow in the future…. It is important to play a role.” The statement cited Japan’s 7th Strategic Energy Plan approved in February this year, which emphasises maximising nuclear energy and explicitly supports replacing ageing reactors with next-generation advanced reactors at existing plant sites.
Kansai stressed the need to review the development of innovative light water reactors and regulation policy as well as to consider the of business environment improvement when making investment decisions. “Therefore, it is not intended to judge the installation of the successor reactor only by the results of this survey. In future, we will explain the voluntary field survey to local people and ask for their cooperation. In addition, we plan to conduct topographical and geological surveys. We will make every effort to ensure the safe and stable operation of nuclear power plants with the highest priority on safety.”
The Mihama NPP comprised three pressurised water reactors which began operation in 1970,1972 and 1976. All three were closed in the wake of the Fukushima accident and in 2015 Kansai decided to decommission the 320 MWe unit 1 and 470 MWe unit 2. In 2016, the Nuclear Regulation Authority approved an application to extend the life of unit 3 to 2036.
Kansai President Nozomu Mori told a press conference: “Given the rapid growth of the data centre and semiconductor industries, electricity demand will continue to increase. Nuclear energy remains crucial for Japan, a resource-poor nation, from the perspective of S+3E (Safety plus Energy Security, Economic Efficiency, and Environmental Protection).” He added: “We will explain the outline of the surveys to the people of Mihama and begin the surveys swiftly…. We will not make a decision based solely on the results.” If the survey results support construction, Kansai is expected to apply for approval from the Nuclear Regulation Authority to move forward with the project.
Reuters reported that Kansai is looking at deploying Mitsubishi Heavy Industries’ (MHI’s) SRZ-1200 advanced light water reactor. MHI launched the SRZ-1200 conceptual design in September 2022. SRZ stands for: Supreme Safety and Sustainability; Resilient light water reactor; and Zero carbon emissions. It is being developed in collaboration with four Japanese utilities – Hokkaido Electric, Kansai Electric, Shikoku Electric and Kyushu Electric.
