Korea Hydro &Nuclear Power (KHNP) has closed unit 4 of South Korea’s Kori NPP in Busan, which has reached the end of its lifespan. The 950 MWe began commercial operations in November 1985. The upgraded reactor is being suspended in accordance with its originally designated 40-year design life. The government is currently considering allowing such reactors to continue operating for an additional 10 years, as permitted by the law.
Kori 2 was closed in April 2023 and Kori 3 in September 2024 after 50 years of operation. KHNP applied to the Nuclear Safety & Security Commission (NSSC) in 2022 for approval to modify Korio 4 for continued operation and the review is currently in progress. “Considering the usual time required for the review process, a decision on unit 2 is expected in the second half of this year, while the results for units 3&4 will likely be announced sometime next year,” an industry official said. Kori-1, which began operation in 1978 with a design lifespan of 30 years, operated for nearly 40 years following an extension. It was permanently closed in 2017 and KHNP applied in 2021 for decommissioning approval, which was granted in June.
KHNP said Kori 4 had achieved 2,059 consecutive days (five cycles) of trouble-free operation until its operating licence expired. Over the past 40 years the unit has generated about 277.3 TWh of electricity. In July 2023, the company completed the public feedback process on the Radiation Environmental Impact Assessment for Continued Operation, and the following November applied for a permit to change the operation of the reactor.
“Continued operation is a key strategy for achieving a stable energy supply and carbon neutrality,” said Kori Plant Director Lee Sang-wook. “We will prioritise the safety of our citizens and pursue continued operation through transparent and fair procedures. Through thorough safety reviews, safety equipment reinforcements, and state-of-the-art facility improvements, Kori unit 4 will become a safer and more efficient power plant.”
