South Korea’s Nuclear Safety & Security Commission (NSSC) has approved continued operation of unit 2 at the Kori NPP in Busan, Gijang County, until 2033. NSSC voted on the Kori 2 extension, passing it with five votes in favour and one against. The 685 MWe pressurised water reactor has been offline since its original 40-year operating permit expired in April 2023.
In April 2022 Korea Hydro & Nuclear Power (KHNP) submitted a safety assessment report for continued operation of Kori 2 applied for a permit for continued operation. This included the outcome of a public opinion survey on the radiation environmental impact assessment.
The Korea Institute of Nuclear Safety (KINS) under the Nuclear Safety and Security Commission (NSSC) conducted a safety review between April 2022 to July 2025. Between March 2025 to September 2025, and the Nuclear Safety Expert Committee undertook a preliminary review of the KINS results and determined that they were appropriate.
NSSC had previously considered the proposal for Kori 2’s continued operation of at meetings in September and October, without reaching a decision. However, it has now concluded that the unit “maintains sufficient safety margins” and meets safety requirements and approved continued operation until 8 April 2033.
KHNP plans to restart Kori 2 in February 2026, after completing improvements and confirming safety through regular inspections by regulatory agencies. It noted: “The plant’s safety and performance will be further enhanced during this period of continued operation through continuous facility improvements and thorough implementation of safety measures.”
Kori 1, which was permanently shut down in 2017 after 40 years of operation, become the first South Korean reactor to enter decommissioning. In May 2021, KHNP submitted its application to dismantle the unit to the NSSC, which approved the decommissioning in June.
Continued operation of Kori 2 is expected to set a precedent for extended operation of other South Korean reactors. KHNP is currently submitting safety assessment reports to the NSSC for review for the continued operation of nine other units with operating licences due to expire before 2030. These include Kori 3&4 (which closed in September 2024 and August this year as their 40-year design lives expired); Hanbit 1&2; Hanul 1&2; and Wolsong 2- 4.
“Continued operation will contribute to the national economy as a stable energy source for future power demand growth, such as for AI and data centres, and will play a significant role in achieving carbon neutrality by 2050,” said Jeon Dae-wook, KHNP acting president. “We will do our best to restart Kori unit 2 at the right time, with safety as our top priority.”
Business Korea commented that “the energy industry breathed a sigh of relief” following the Kori 2 decision on Nov. 13 as the decision to grant continued operation approval for Kori Unit 2 in Gijang County, Busan, was announced. According to “an industry insider”: “While the government has been voicing negative opinions about new NPPs, it’s positive that the stance of at least not blocking continued operation of existing plants has been confirmed.”
The paper pointed to the excessively long time required to evaluate continued operation. Even though both safety evaluation institutions and review institutions were mobilised for Kori 2, it took three years and seven months to reach final approval. A review for continued operation, requires preparation of documents including a periodic safety review (PSR) by KINS and a post-construction environmental report (PER) taking into account public opinion as well as deliberation by NSSC. When political factors are added to this, the continued operation period becomes even shorter. Kori 3&4 are expected to face similar situations.
Business Korea said calls are growing for improvements to the review system. “The NSSC’s review capacity has limits while ageing nuclear plants continue to increase,” an official was quoted as saying. “At least during periods when continued operation reviews are concentrated, the NSSC and KINS organisations should be expanded to ensure nuclear plants can operate in a timely manner.”
There are also calls to increase the length of life extensions. Lee Ki-bok, president of the Korean Nuclear Society, emphasised, “Most developed countries extend operating licence periods by 20 years at once. Considering the administrative costs involved in design extensions, we should consider expanding nuclear plant life extension periods from 10 to 20 years.”
This is the third time an additional operational permit has been granted for a nuclear reactor that has completed its 40-year operational period. It follows Kori-1 in 2008 and Wolseong-1 in 2015. It is also the first approval since the inauguration of the Lee Jae-myung government, which had appeared ambiguous on nuclear policy. According to industry observers, the government’s energy policy appears to have shifted from the nuclear phase-out of the Moon Jae-in administration to a practical energy mix.
