South Korea’s AI and Chip Boom Is Forcing a New Nuclear Power Debate

South Korea’s power planning is being rewritten around an industrial question: how can the country supply always-on electricity to semiconductor fabs and AI data centres while also electrifying transport and heating and reducing coal use?

Climate, Energy and Environment Minister Kim Sung-hwan has said demand will surge as Samsung Electronics and SK Hynix expand chip production and new AI data centres are built. In a Reuters interview, he said AI-related needs alone could add 25–30 GW of demand; electric vehicles and the move away from gasoline-powered transport add further pressure. 9

Why the 2040 forecast changed so sharply

The government’s revised outlook puts South Korea’s 2040 peak power demand at 158.4–165 GW, up 26.6–26.8 GW from the April estimate of 131.8–138.2 GW. Advanced industries and AI data centres are projected to represent 36.2–36.5 GW of 2040 peak demand. 722

That change is not simply an abstract national forecast. Four planned fabs in the southwestern cluster could consume electricity equal to 70–80% of the present annual electricity use of Gwangju, North Jeolla and South Jeolla combined, according to analysts cited by Reuters. 20

The comparison often used in the policy debate illustrates the scale rather than prescribing a technology choice: covering the 26.8-GW increase entirely with 1.4-GW APR1400 reactors would require about 19 reactors. 7

What Kim said about new nuclear plants

Kim’s position is that additional nuclear capacity must be examined, not that it has already been approved. He said semiconductor production needs stable power around the clock and that meeting the growing load with renewable energy alone would be difficult, making a prompt review of additional nuclear reactors necessary. 10

The decision is being incorporated into the 12th Basic Plan for Electricity Supply and Demand, South Korea’s long-term roadmap through 2040. Kim has said the government had not reached a conclusion on whether additional reactors would be included and would consider the generation mix through public discussion rather than setting the outcome in advance. 2541

Nuclear’s appeal in this debate is its ability to supply large volumes of low-carbon electricity continuously, matching the operating profile of fabs and data centres. But that case does not settle concerns around safety, radioactive-waste management, siting and local acceptance. The supplied reporting does not provide a reliable national poll or quantified split of public support and opposition, so no precise claim about public sentiment can be made.

South Korea’s current electricity mix

South Korea operates 26 nuclear reactors with total capacity of 26.05 GW, according to Reuters reporting from 2025. 21

In 2024, nuclear generated 188.8 TWh, or 31.7% of the country’s electricity—its largest single generation source. Coal and LNG each generated 167.2 TWh, or 28.1%, while renewables produced 63.2 TWh, or 10.6%. 17

The government’s renewable target is far larger than today’s deployment: capacity is planned to rise from 37 GW in 2025 to 220 GW by 2040. 40 That target underscores that the policy question is not nuclear or renewables. It is how to combine variable renewable generation, firm generation, storage and transmission so that fast-growing industrial loads can be served reliably.

Why the southwest chip cluster may not need its own reactor

Kim has said the currently expected 6.3 GW of demand for the southwestern semiconductor cluster can be supplied with relatively limited additions to existing sources. A dedicated reactor is therefore not necessarily required for that cluster at its currently anticipated scale. 12

The harder issue is system design: whether the grid can deliver dependable power to new industrial locations, and whether enough generation and transmission can be built in time. The government has said it will provide the cluster’s electricity and industrial-water needs while overhauling the grid to handle rising demand from fabs and AI servers. 11

Solar expansion is central to the national renewable plan, while LNG is likely to remain important as dispatchable supply when renewable output is low. Kim has said LNG’s generation share will inevitably rise in discussions over the next power plan, despite the planned renewable build-out. 23

Coal’s place after 2040

South Korea’s policy direction is a coal phaseout by 2040, with nuclear continuing to play a major role alongside renewables and an expanded power grid. 49 The supplied evidence does not confirm a final policy to keep particular coal plants in emergency reserve after that date. Such a role may arise in reliability debates, but it should not be treated as an adopted plan.

The key takeaway is that South Korea’s AI and semiconductor strategy has become a power-system strategy. The 12th plan will need to decide not only how much electricity the country needs, but where firm power, renewable generation, transmission and flexibility will be built—and whether the resulting gap justifies more nuclear capacity.