As the U.S. government, which needs massive electricity due to the growth of the artificial intelligence (AI) industry, is reviving nuclear power plants it shut down years ago, some say Korea should consider restarting reactors slated for decommissioning. The United States is even moving to restart the Three Mile Island plant, once synonymous with risk after a major nuclear accident.
Unlike the United States, which uses nuclear plants for more than 80 years, Korea moves to shut them down after about 40 years. Kori Unit 1, which operated for 40 years starting in 1978, is permanently closed, and Wolseong Unit 1, which ran for 35 years from 1982, is permanently shut down. Experts said that in the United States these plants would run 80 years, but in Korea they are being discarded after 40 years due to political issues.
According to foreign media on the 24th, on the 19th (local time) the U.S. Department of Energy (DOE) announced it would provide a $1 billion (about 1.5 trillion won) federal loan to Constellation Energy, the operator of the Three Mile Island plant in Pennsylvania. The funding is to restart Three Mile Island Unit 1, which halted operations in 2019.
Three Mile Island is where the worst nuclear accident in U.S. history occurred in 1978. Unit 2, where the accident happened, was permanently closed. After the accident, Unit 1 at the same plant generated power for more than 40 years, but it stopped in 2019 due to declining competitiveness as natural gas prices fell amid the U.S. shale gas revolution.
Following Three Mile Island, the Duane Arnold plant in Iowa (halted in 2020) and the Palisades plant in Michigan (halted in 2022) are also preparing to restart. In July, the U.S. Nuclear Regulatory Commission (NRC) approved the restart of the Palisades plant. The plant could restart as early as next month.
AI data centers are at the heart of bringing closed nuclear plants back to life. Data centers are facilities that provide server computers and network lines or store IT infrastructure for services. AI data centers, which aggregate and process vast amounts of data, are called "power hogs."
The Korea Energy Economics Institute (KEEI) estimated that, as of 2024, global data centers consume about 415 terawatt-hours (TWh) of electricity, a figure expected to reach about 945 TWh by 2030. The 415 TWh amounts to 70% of the electricity used by all of the Republic of Korea in one year (600 TWh in 2023).
The electricity generated by restarting closed nuclear plants is expected to be monopolized by big tech corporations' AI data centers. Microsoft agreed to purchase 835 MW of power for 20 years from the restart of Three Mile Island Unit 1. Google plans to receive 615 MW for 25 years from the restart of the Duane Arnold plant. Meta agreed to receive 1.1 GW for 20 years from the Clinton plant in Illinois, which had been slated for closure.
Nuclear power is regarded as the optimal energy source to meet data center power demand because it can supply large amounts of electricity stably 24 hours a day, unaffected by weather and seasons.
There are calls for Korea to increase nuclear utilization as power demand surges with the rise of AI data centers. According to IDC Korea, there were 165 domestic data centers as of last year, and power demand is expected to grow from 4,461 MW this year to 6,175 MW in 2028.
In the power industry, there is cautious discussion of using closed plants such as Kori Unit 1 and Wolseong Unit 1. Kori Unit 1 received a 10-year extension after its design life ended but was permanently shut down as of June 18, 2017. From this month, dismantling work in non-radiological controlled areas has begun. Wolseong Unit 1 is proceeding toward decommissioning.
Jung Yong-hoon, a professor of nuclear engineering at KAIST, said, "In the United States, a plant would run for 80 years, but in Korea we use it for only 40 years. Every shutdown of a domestic nuclear plant was for political reasons. Reviving closed plants such as Kori Unit 1 and Wolseong Unit 1 is fully feasible technically. Although it is sensitive because the current administration is not friendly to nuclear power, at least for Wolseong Unit 1 we should discuss a plan to restart it by replacing internal components."
Noh Dong-seok, a research fellow at the Seoul National University Nuclear Policy Center, said, "Restarting Kori Unit 1 and Wolseong Unit 1 is fully feasible technically. Economically, repairing and using them longer is better than building new ones. However, because a shutdown decision has already been made institutionally, reversing it appears impossible. To restart and sell electricity, we would have to revise multiple laws starting with the Electric Utility Act, which would be difficult under the current administration."
There is also a rebuttal. Lee Jung-yoon, head of Nuclear Safety and Future and a former engineer who participated in the reactor design of Wolseong Units 2, 3 and 4, said, "U.S. nuclear safety standards are far stricter than those in Korea. Domestic plants have many problems by international standards. Wolseong Unit 1 had its containment barrier damaged and leaked radioactive contaminated water into the sea, and it was not properly fixed. Its capacity factor is also 50%, so it has already been assessed as uneconomical. It is neither economical nor safe."
A KHNP official said, "We could review whether revival is technically possible, but we first need to examine whether it is economical."