Kansai Electric Power Revises Nuclear Emergency Disaster Prevention Business Plans for Three Nuclear Power Plants

Kansai Electric Power Co., Inc. announced on August 27 that it has revised the nuclear operator disaster prevention business plans for the Mihama, Takahama, and Oi nuclear power plants in accordance with Japan's Act on Special Measures Concerning Nuclear Emergency Preparedness, and filed them with the Prime Minister and the Nuclear Regulation Authority on the same day. The revisions pertain to nuclear emergency disaster prevention arrangements at the three nuclear power plants. Kansai Electric Power stated that it will continue to ensure the safety of the nuclear power plants and enhance nuclear emergency disaster prevention measures in accordance with the relevant plans. According to the documents, the consultation period prior to the revisions was from May 13 to July 30, 2026, totaling 79 days. The consultation parties included the local governments where the nuclear power plants are located and related neighboring local governments.

2026-08-27

Investigation into Automatic Shutdown of Unit 3 at Japan's Ohi Nuclear Power Plant: Damage Found in Exciter Rotating Rectifier

Kansai Electric Power reported on August 19 that Unit 3 of the Ohi Nuclear Power Plant experienced an automatic generator trip triggered by a generator loss-of-field alarm at 23:56 on August 8, followed by an automatic reactor shutdown. At the time of the event, the unit was operating stably at rated thermal power. The company stated that the event caused no radiological impact on the environment. The loss-of-field alarm is used to indicate an abnormal state in the magnetic field generated inside the generator. Following the incident, Kansai Electric conducted on-site inspections of equipment related to generator magnetic field establishment, including the generator, exciter, and automatic voltage regulator (AVR). Among these, the exciter is used to establish the magnetic field for the generator...

2026-08-19

Automatic Shutdown of Unit 3 at Oi Nuclear Power Plant During Operation; Kansai Electric Power to Investigate Cause from the 12th

Unit 3 of the Oi Nuclear Power Plant in Fukui Prefecture, Japan, experienced an automatic shutdown during operation in the early hours of the 9th. Operator Kansai Electric Power stated that the fault is related to an internal abnormality in the generator and plans to formally begin a cause investigation from the 12th. Currently, there is no clear timeline for when the unit can resume operation. According to reports, an alarm related to loss of magnetic field occurred inside the generator used for power generation at the time of the incident, after which the generator stopped, and the reactor in operation also automatically shut down. On the 10th, Kansai Electric Power visited the Fukui Prefectural Government to apologize for the fault and report on subsequent response measures. Yuichiro Sakamoto, head of the Fukui Prefecture Disaster Prevention and Safety Division, pointed out that following a steam leak fault at Mihama Nuclear Power Plant Unit 3 in May this year, an unexpected emergency shutdown of a reactor in operation occurring within a short period may undermine public trust in nuclear safety. Local government authorities have demanded that the operator promptly identify the cause and implement measures to prevent similar issues from recurring.

2026-08-11

Unit 3 of Japan's Ohi Nuclear Power Plant Automatically Shuts Down

Kansai Electric Power Co. announced in the early hours of the 9th that Unit 3 of the Ohi Nuclear Power Plant, located in Ohi Town, Fukui Prefecture, Japan, automatically shut down during operation. The unit has a generating capacity of 1.18 million kilowatts. According to Kansai Electric Power, at around 23:56 on the 8th, an alarm was triggered at the unit, indicating that the generator had lost the conditions required to produce a magnetic field. Subsequently, the generator automatically stopped operating, and the reactor also automatically shut down. Preliminary information suggests that the anomaly may involve the exciter, a device used to establish the magnetic field for the generator. Kansai Electric Power stated that no radioactive material leakage occurred as a result of this incident, and there was no radiological impact on nearby personnel or the environment. The cause of the malfunction...

2026-08-10