Power Facilities Must Increase 1.4 Times in 15 Years... Will New Nuclear Plants Be Added in the 12th Basic Plan? [Digging Energy]

Nuclear Sector: "To Achieve Carbon Neutrality,
Bold Expansion of Nuclear and Other Zero-Carbon Power Needed"
24 Large Reactors and 12 SMRs by 2050 Proposed
Utilization of Canceled Nuclear Plant Sites Suggested
Additional Power Demand in the 12th Plan: 2.5GW
Concerns Raised Over Suitability for Two Large New Reactors

A panoramic view of Saeul Nuclear Power Plant. Korea Hydro & Nuclear Power Company

As the establishment of the 12th Basic Plan for Electricity Supply and Demand, which will outline South Korea's long-term power facility strategy through 2040, approaches, there is growing interest in whether additional nuclear power plants will be included. The previous 11th plan had decided to add one new large-scale nuclear power plant and one small modular reactor (SMR) by 2038.

The nuclear energy sector maintains that additional nuclear power plant construction should also be included in the 12th plan. They argue that, given the difficulty of achieving the government’s carbon neutrality target solely with renewable energy, nuclear power—which is a zero-carbon energy source—must be substantially expanded to meet increasing electricity demand.

At the "Integrated Energy Technology Strategy for Achieving Carbon-Neutral Energy Mix" forum, jointly hosted on April 29 by the Korean Institute of Electrical Engineers, the Korean Society for New and Renewable Energy, and the Korean Nuclear Society, Professor Shim Hyungjin of the Department of Nuclear Engineering at Seoul National University (Vice President of the Korean Nuclear Society) projected that the power generation required in 2050 under the government’s carbon neutrality scenario would amount to 1,257.7 kilowatt-hours (kWh). He emphasized, "To achieve this, it is essential to aggressively expand zero-carbon power sources."

Professor Shim stated, "If power generation is overly reliant on a specific source, it could lead to astronomical costs and grid instability. Therefore, the key task is to establish an optimal energy mix that balances cost, grid stability, and energy security."

He proposed a scenario in which, every year from 2039 to 2050—after the 11th plan—two large-scale nuclear power plants and one SMR would be constructed, with any remaining power needs to be met through hydrogen-fired power generation. This would require the construction of 24 additional large-scale nuclear power plants and 12 additional SMRs.

This scenario assumes that renewable energy will cover 30% of total power demand by 2050. According to Professor Shim's analysis, if the trend of the 11th plan continues linearly, renewable energy would account for 24.8% of total demand in 2050. He explained that even with a more aggressive build-out of renewable energy facilities than envisioned in the 11th plan, other zero-carbon sources such as nuclear and hydrogen power will still be necessary to achieve carbon neutrality.

Professor Shim also suggested replacing the combined total of 3.1GW—planned for introduction through competition among zero-carbon sources (1.5GW in 2035–2036) and reserved sources (1.6GW in 2037–2038) under the 11th plan—with nuclear power.

To build 24 new nuclear power plants as advocated by the nuclear energy sector, at least three additional large-scale nuclear sites would be required. Currently, each nuclear site operates four large-scale nuclear reactors. Professor Shim stated, "If we utilize the two sites that the previous Moon Jae-in administration had planned for nuclear construction but then canceled, it is feasible." The proposal is to use the Cheonji Nuclear Power Plant site in Yeongdeok, North Gyeongsang Province and the Daejin Nuclear Power Plant site in Samcheok, Gangwon Province as new nuclear power sites.

Progressive groups that have advocated for expanding renewables have consistently opposed further nuclear construction, arguing that nuclear power, as an inflexible power source, is difficult to control in output and therefore conflicts with highly variable renewable energy sources.

In response, Korea Hydro & Nuclear Power is developing technology for its latest reactors, such as the APR1400, to reduce output by up to 50%. The innovative small modular reactor (i-SMR) currently under development domestically incorporates technology that allows output to be lowered from 100% to as little as 20%.

The nuclear energy sector explains that, since nuclear output can be reduced during periods of high renewable generation, nuclear and renewables are in fact complementary.

Kim Hangon, Head of the i-SMR Technology Development Project, said, "The i-SMR currently under development is capable of daily load-following operation between 100% and 20% output, and the output can vary by up to 40% per hour." The i-SMR is designed to allow for up to 300 load-following operations per year.

However, there are concerns due to South Korea’s lack of experience with load-following operation in nuclear power plants. Kim stressed, "Just as even the most advanced car is useless if not driven, it is crucial to accumulate experience with load-following operation in nuclear plants."

At the forum, Assemblywoman Kim Sohee of the People Power Party stated, "Nuclear energy plays a vital role as a zero-carbon power source," and suggested, "It would be desirable to deploy SMRs in areas where coal-fired plants are being phased out."

Meanwhile, power demand is expected to continue rising under the 12th plan. At the "12th Basic Plan for Electricity Supply and Demand Power Demand Forecast Public Forum" held on April 22, the General Committee for the Plan projected that power demand would reach 131.8GW by 2040 in the base scenario.

This is 2.5GW higher than the 129.3GW forecast in the 11th plan for 2038. Given that Korea’s installed power capacity in 2025 is expected to be 100.9GW, this means the nation will need to increase power facilities by about 1.4 times over the next 15 years.

The General Committee expects that, despite a slowdown in economic growth, power demand will increase due to the expansion of advanced industries such as semiconductors, the spread of artificial intelligence (AI), resulting in more data centers, and the trend toward electrification. Notably, under the base scenario, by 2040 power consumption due to electrification will reach 112.6 terawatt-hours (TWh), far surpassing advanced industries (29.3TWh) and data centers (26.5TWh).

The domestic large reactor type, APR1400, is designed for 1.4GW per unit, and for efficiency, it is customary to construct two units at a time. This means new nuclear construction is only feasible if additional power demand exceeds 2.8GW. A source in the nuclear power sector commented, "If we only look at the 2.5GW increase in power demand predicted by the 12th Basic Plan General Committee, it may be difficult to justify building additional large reactors."

The 12th Basic Plan General Committee intends to announce a draft of the plan as early as the first half of the year, following public forums by subcommittees on facility planning, grid innovation, and more. Lee Ho-hyun, Second Vice Minister of the Ministry of Climate, Energy and Environment, indicated that as renewables expand, the 12th plan will place greater emphasis on flexible operation of power facilities.

Vice Minister Lee said, "If the power grid does not become flexible throughout all four seasons, 365 days a year, there will come a time when it will be difficult to ensure stable electricity supply and demand. The 12th plan will be the first to consider the electricity supply and demand situation for all 365 days of the year."

This content was produced with the assistance of AI translation services.