KEPCO’s Plan to Construct New Nuclear Reactor: A Step Forward from ‘Post-2011 Earthquake’ Policy

Editorial

15:33 JST, July 23, 2025

After being frozen for many years following the 2011 Great East Japan Earthquake, movement has begun toward the construction of new nuclear reactors. The hope is that Kansai Electric Power Co. will steadily proceed with the plan while carefully gaining the understanding of the public.

KEPCO has announced that it will resume a geological survey on the premises of its Mihama nuclear power plant in the town of Mihama, Fukui Prefecture, in preparation for the construction of a new nuclear reactor. The company started the survey in 2010, but it was suspended following the accident at Tokyo Electric Power Company Holdings, Inc.’s Fukushima No. 1 nuclear power plant in 2011.

Since the earthquake, there has been strong caution about the use of nuclear power plants. The last nuclear reactor that was newly built in Japan was the No. 3 reactor at Hokkaido Electric Power Co.’s Tomari nuclear power plant, which went into operation in 2009.

In recent years, household budgets have been suffering from rising electricity bills due to higher energy prices caused mainly by Russia’s aggression against Ukraine and instability in the Middle East.

The public has become more aware of energy security, and understanding of the need for nuclear power generation that is compatible with decarbonization has grown.

KEPCO may have now clearly expressed its intention to build a new nuclear reactor in light of these changes.

KEPCO envisions that the surveying will take around several years. After that, it plans to submit its construction plan to the Nuclear Regulation Authority. It could take about 20 years from the survey to the construction of a new reactor being completed, the company said. Concerns about the safety of nuclear power plants are deep-rooted. KEPCO should continue to make meticulous efforts to gain the understanding of local communities.

The Mihama nuclear power plant has three reactors. KEPCO has decided to decommission the No. 1 and No. 2 reactors, and the No. 3 reactor is currently in operation. KEPCO said it will consider constructing an “advanced light-water reactor,” a next-generation nuclear reactor that is said to be very safe and to generate power very efficiently.

KEPCO must thoroughly explain the safety of the new technology.

After the Great East Japan Earthquake, the government stated that “dependency on nuclear power generation will be lowered to the extent possible.” However, former Prime Minister Fumio Kishida approved the construction of new nuclear reactors in 2022, changing that policy drastically.

Behind this policy shift is the recognition that it is essential to promote the development of data centers for artificial intelligence, which use vast amounts of electricity, in order to strengthen international competitiveness amid the advancement of digitalization. The government has also attached importance to supporting the manufacturing industry through this inexpensive electric power source and reducing the burden on household budgets.

In its Strategic Energy Plan, which was approved at a Cabinet meeting in February this year, the government has indicated its policy to raise the ratio of nuclear power in electric power sources from 8.5% in fiscal 2023 to about 20% in fiscal 2040. This is equivalent to the electricity produced by about 30 nuclear reactors.

There are currently 33 nuclear reactors in Japan, 14 of which have resumed their operations. Although it is possible for a nuclear reactor to operate for more than 60 years under certain conditions, the stable supply of electricity will be threatened if new reactors are not built. Other electric power companies, such as Kyushu Electric Power Co., will also need to move forward with considering the construction of new reactors.

(From The Yomiuri Shimbun, July 23, 2025)