As Unit 2 of the Kori Nuclear Power Plant, which received approval for a 10-year life extension, now faces a situation in which it can actually operate for only 7 years and 2 months, voices are calling to improve the life extension system and lengthen the period to 20 years.
Unit 2 of the Kori Nuclear Power Plant in Gijang, Busan, which was halted for nearly three years under Moon Jae-in's nuclear phaseout policy, will generate electricity again starting in February next year. Although it received approval for a 10-year life extension, it remained shut for 2 years and 7 months after the operating expiry date (Apr. 8, 2023), and after subtracting a three-month overhaul period ahead, the actual operable period is only 7 years and 2 months.
According to the nuclear industry on the 14th, KHNP, the nuclear power plant operator, received approval for continued operation of Kori Unit 2 through the 224th plenary meeting of the Nuclear Safety and Security Commission on the 13th. This conclusion came at the third meeting after the continued operation approval for Kori Unit 2 failed to pass twice, on Sept. 25 (the 222nd) and Oct. 23 (the 223rd).
KHNP said, "After completing the ongoing facility upgrades and confirming safety through regular inspections by the regulator, we aim to restart in February 2026."
Korea Hydro & Nuclear Power (KHNP) missed the optimal window to apply for continued operation of Kori Unit 2, resulting in a shortened operating period. Kori Unit 2 is a pressurized water reactor (a method of producing steam by pressurizing high-temperature water) nuclear plant that began commercial operation on Aug. 10, 1983. After operating for 40 years, its operating license period ended on Apr. 8, 2023, and it was shut down.
◇ The 10 years not guaranteed due to review delays... Kori Unit 1 and Wolsong Unit 1 also had "lost operating periods"
As the life of Kori Unit 2 was nearing expiration at the time, and the Moon Jae-in administration was operating policy under a nuclear phaseout stance, KHNP delayed not only the application for an operating change to determine continued operation but also the submission of the safety assessment report. With the review application itself being late and the discussion process dragging on, Kori Unit 2 received approval for continued operation only after being idle for 2 years and 7 months.
Kori Unit 1 and Wolsong Unit 1, which had previously received approval for continued operation, were also not guaranteed the additional 10-year period. This resulted from receiving life extension approval after the operating license expiry date, as with Kori Unit 2.
KHNP applied for an operating change to extend the operating period by 10 years on Mar. 2, 2007, three months before the Kori Unit 1 life expiry date (Jun. 18, 2007). At the time, before the launch of the Nuclear Safety and Security Commission, the Ministry of Science and ICT was responsible for the life extension decision for Kori Unit 1. Because the ministry handled both nuclear promotion and regulation, the time required to decide on continued operation was relatively short at eight months.
Approval for continued operation of Kori Unit 1 came nine months after the application, on Dec. 11, 2007, six months past the life expiry date. After preparations, it restarted on Jan. 9, 2008, and it was permanently shut on Jun. 18, 2017, leaving only 9 years and 5 months of restarted operation out of the 10-year extension approval. Even so, it is the case that operated closest to the 10-year extension.
Approval for continued operation of Wolsong Unit 1 (Feb. 27, 2015) came only after 2 years and 3 months had passed since the life expiry date (Nov. 20, 2012). After the Fukushima nuclear accident in Japan in March 2011, the Nuclear Safety and Security Commission was newly established as a presidential commission in October of that year, causing the review discussions to drag on. With the commission's establishment, the review system and criteria were overhauled, and administrative delays occurred as existing reviews and procedures were reexamined.
Even then, it was shut early after 4 years and 6 months of restarted operation on grounds of low economic viability. At the time, allegations were raised that the Moon Jae-in administration downplayed and manipulated the economic assessment of Wolsong Unit 1 to achieve its nuclear phaseout policy goals, and the related trial is still ongoing.
◇ U.S. and Japan extend by 20 years and operate during reviews... Korea also needs urgent system improvements
The United States and Japan, which began operating commercial nuclear plants 10 to 20 years earlier than Korea, set the nuclear life extension cycle at 20 years. In the United States, plants can be used for up to 80 years with two extensions after the initial 40 years (40+20+20). Japan is revising its system to allow operation for 60 years (40+20+α) or more on the condition of periodic safety assessments.
The domestic nuclear industry argues for a "20-year life extension cycle." Under the International Atomic Energy Agency (IAEA) safety standards, 12 countries including the Netherlands and Hungary have set the extension cycle at 20 years.
Unlike Korea, which halts nuclear plants during continued operation reviews, the United States allows plants to keep operating during the review period. Applications for continued operation can be filed starting 20 years before the operating license expires, securing sufficient review time and preventing shutdowns. If issues arise during the review, the existing license is surrendered and operation is halted. Because the extension period begins from the date of operation resumption, the actual restarted operation period is also 20 years.
Jung Yong-hoon, a professor in the Department of Nuclear and Quantum Engineering at KAIST, said, "If judged by U.S. standards, Korea's nuclear plants would have no problem obtaining approval to operate for 80 years. The delay in continued operation reviews was due to external factors, not technical issues. As Kori Unit 2 stood idle during three years of re-review, 1 billion won a day was lost."