Unit 2 of Japan's Shimane Nuclear Power Plant Completes Periodic Inspection and Resumes Commercial Operation After About 7 Months

The Chugoku Electric Power Company (Japanese: 中国電力株式会社), a large integrated electric power company responsible for supplying electricity to 5 prefectures in the Chugoku region of western Honshu, Japan, announced on September 16 that Unit 2 of the Shimane Nuclear Power Plant has successfully completed the periodic inspection that began in February this year and officially resumed commercial operation on the 16th, returning to power supply after about 7 months. According to Chugoku Electric Power's estimate, in the overall power source mix, nuclear power generation will account for about 15% of the company's total power generation for this fiscal year, and this level of generation is expected to meet about 60% of the electricity demand of the two San'in prefectures. In addition, since Unit 2 of the Shimane Nuclear Power Plant has reached 37 years since it began commercial operation, Chugoku Electric Power also collected, during this periodic inspection, data used as the basis for assessing the "special inspection" required for future extended operation beyond the standard service period (exceeding the 40-year operating limit).

2026-09-17

Safety review items for Shimane Nuclear Power Plant Unit 3 confirmed, operation planned for 2030

The Nuclear Regulation Authority (NRA) of Japan conducted a safety review of Shimane Nuclear Power Plant Unit 3 on September 10. This review is a necessary procedure before the unit can be put into operation. Chugoku Electric Power Company of Japan has been constructing Shimane Nuclear Power Plant Unit 3 since 2005 and has been undergoing NRA review since 2018. At the review meeting that day, Chugoku Electric Power Company gave explanations regarding earthquake, tsunami, and severe accident response measures for Unit 3. According to the meeting, all review items were confirmed on September 10. Next, Chugoku Electric Power Company will submit a revised document incorporating the relevant content discussed at previous review meetings. The NRA is expected to prepare a draft review report based on this...

2026-09-11

NRA Commissioner Inspects Radiation Management at Shimane Nuclear Power Station

Reiko Kanda, a Commissioner of the Nuclear Regulation Authority (NRA) of Japan, visited Matsue City, Shimane Prefecture, from September 7 to 8 to inspect radiation level management and on-site inspection work at the Shimane Nuclear Power Station. The NRA has a dedicated inspection team stationed at the Shimane Nuclear Power Station and conducts a related inspection once a year to confirm that resident inspectors can properly manage and monitor radiation levels. On September 8, the NRA inspected the emergency response center used by the nuclear power station in the event of a severe accident, focusing on confirming the inspectors' emergency response procedures. Reiko Kanda observed the inspection process on site. Reiko Kanda stated that the inspection work was carried out properly and that this inspection will serve as a reference for the NRA's future work.

2026-09-10

Tottori Prefecture nuclear safety advisory council approves safety of MOX fuel plan for Shimane Unit 2

The Tottori Prefecture Nuclear Safety Advisory Council held a meeting in Yonago City on September 6 and submitted an opinion on the MOX fuel power generation project planned by Chugoku Electric Power Co. for Unit 2 of the Shimane Nuclear Power Station. The opinion stated that, based on explanations provided by Chugoku Electric Power Co. and the Japanese government, the safety of the project can be ensured. The Shimane Nuclear Power Station is located in Matsue City, Shimane Prefecture. Chugoku Electric Power Co. plans to use mixed oxide fuel, or MOX fuel, consisting of uranium and plutonium, in Unit 2. This type of power generation is also referred to as plutonium thermal power generation in Japan. The opinion also...

2026-09-07

Shimane Nuclear Power Station Unit 2 Resumes Power Generation

Chugoku Electric Power Co. reported on August 19 that Unit 2 of the Shimane Nuclear Power Station resumed power generation at 2:00 p.m. that day through generator synchronization and began supplying electricity to the grid. Unit 2 of the Shimane Nuclear Power Station uses a boiling water reactor with a rated generating capacity of 820,000 kilowatts. Chugoku Electric Power Co. stated that it will prioritize safety, conduct comprehensive inspections of equipment operating conditions, and prepare for the unit to resume commercial operation as scheduled on September 16. ...

2026-08-19

Restart of Shimane Nuclear Power Plant Unit 2 Delayed to August 19

Chugoku Electric Power announced that the restart of power generation at Shimane Nuclear Power Plant Unit 2 has been postponed from the originally scheduled August 18 to August 19. Unit 2 of the Shimane Nuclear Power Plant has been shut down since February this year for routine inspections. After approximately six months of inspections, the reactor was started on August 13, and power generation was originally planned to resume on August 18 after reaching criticality, the state of a sustainable nuclear fission chain reaction. On August 18, at a special committee meeting on Shimane Nuclear Power Plant measures held in Matsue City, Chugoku Electric Power explained that the restart of power generation was delayed by one day, mainly because the restart process requires careful progression and additional time is needed to confirm the status of related equipment...

2026-08-19

Shimane Nuclear Power Station Unit 2 restarted and reached criticality

Chugoku Electric Power Co. announced on August 13 that it started up the reactor of Unit 2 at the Shimane Nuclear Power Station at 10:00 that day, and the unit reached a critical state at 12:14. Unit 2 of the Shimane Nuclear Power Station is a boiling water reactor with a rated electrical output of 820,000 kilowatts. Criticality refers to the state in which nuclear fission reactions in the reactor core can be sustained, and is one of the key milestones in the unit restart process. According to the plan, the unit will resume power generation, i.e., synchronize the generator to the grid, on August 18, 2026, and is expected to resume commercial operation on September 16, 2026. Chugoku Electric Power Co. stated that it will continue to prioritize safety and steadily advance all subsequent procedures.

2026-08-13

Shimane Nuclear Power Station Unit 2 completes containment vessel-related repairs, scheduled to resume commercial operation on the 16th of next month

The Shimane Nuclear Power Station Unit 2, located in Matsue City, Japan, is scheduled to resume commercial operation next month. Recently, part of the reactor containment vessel repair work at the unit was opened to the public, showcasing key construction steps before the resumption of operation. Unit 2 of the Shimane Nuclear Power Station resumed operation in December two years ago. Since February this year, the unit has been shut down for routine operational inspections. In accordance with relevant legal requirements, nuclear power units must undergo equipment disassembly inspections and replacement of related components within 13 months after the previous inspection is completed. On August 3, a dedicated crane was used on site to lift a cover weighing approximately 60 tons to the top of the reactor containment vessel. Workers completed the tightening of 120 bolts that day...

2026-08-13

Shimane Nuclear Power Station Unit 2 scheduled inspection completion date moved up to September 16

Chugoku Electric Power Co., Inc. announced on August 5 that the schedule for the 18th periodic utility inspection of Shimane Nuclear Power Station Unit 2 has been revised, with the inspection completion date moved up from September 17, 2026 to September 16, and the power generation resumption date moved up from August 19 to August 18. Shimane Nuclear Power Station Unit 2 is a boiling water reactor unit with a rated electrical output of 820 MW. The unit was shut down on February 9, 2026 and entered its 18th periodic utility inspection. The reason for this adjustment is that, during the reactor start-up preparation work, the procurement of the nitrogen gas source used to fill the reactor containment vessel was completed earlier than planned, allowing the related work to be advanced accordingly...

2026-08-05

Shimane Nuclear Power Plant Unit 2 Completes Fuel Replacement and Installs Containment Vessel Head

Chugoku Electric Power Co. on August 4 disclosed the installation work of the containment vessel head for Unit 2 of the Shimane Nuclear Power Plant. The unit is currently undergoing periodic inspection, with major procedures such as nuclear fuel replacement already completed. Unit 2 of the Shimane Nuclear Power Plant, located in Matsue City, Japan, was restarted two years ago. Chugoku Electric Power Co. halted the unit's operation in February this year and has been conducting periodic inspections as scheduled. To date, all 560 nuclear fuel assemblies in the unit have been removed, and safety confirmation of the reactor core has been completed. Approximately 120 of these fuel assemblies were replaced with new nuclear fuel assemblies, followed by the phase of resetting related equipment and confirming seal integrity...

2026-08-05

Chugoku Electric Power Submits Third Amendment to Reactor Installation Change Permit Application for Shimane Nuclear Power Plant Unit 3 to Regulatory Authority

Chugoku Electric Power Co., Inc. announced on July 29 that it had submitted the third amendment to the reactor installation change permit application for Unit 3 of the Shimane Nuclear Power Plant to the Nuclear Regulation Authority (NRA) on the same day. The company stated that this amendment adjusts the application content for related equipment at the plant based on previous review findings. This includes reclassifying certain equipment already installed for Unit 2, such as the emergency response center, for shared use between Unit 2 and Unit 3. According to reports, Chugoku Electric Power had previously submitted two amendments to the reactor installation change permit application for Unit 3 of the Shimane Nuclear Power Plant, on December 22, 2021, and June 29, 2022, respectively.

2026-07-29