For decades data centres did their work quietly, out of sight and largely out of mind. That phase is over, and nowhere is the change starker than in South Korea, where the government now expects artificial intelligence alone to lift national power demand by 25 to 30 gigawatts. Kim Sung-whan, the country's minister of climate, energy and environment, told Reuters this month that meeting it could require the equivalent of about 20 new nuclear reactors, in a nation that currently runs 26. Asia's fourth-largest economy is redrawing an energy roadmap out to 2040, and the central question is no longer which chips it can buy. It is where the electricity will come from.
The numbers behind Seoul's urgency are concrete. Samsung and SK Hynix, two of the world's biggest memory-chip makers, have pledged new factories in the country's southwest as part of an 800 trillion won, or roughly 590 billion dollar, national project, with completion dates pulled forward from the mid-2040s to the early 2030s. Nvidia and other US firms have told the government they want to build data centres in Korea precisely because its power supply is dependable. To keep it that way, the Ministry of Science and ICT has raised its energy-technology research budget 48 percent to a record 733.6 billion won, with small modular reactor funding up 55.7 percent and nuclear-fusion spending more than doubling. "In the AI era," said Representative Hwang Jung-a, who obtained the figures, "national power will be determined by electricity."
Nuclear is the politically fraught centre of the plan. It already supplies just under a third of Korean power, and a state-run poll found 79 percent of respondents backing new plants in the roadmap. Yet in the city of Ulsan, a potential site, a civic group gathered more than 10,000 signatures opposing further reactors on safety grounds. Kim was candid about the bind: renewables account for only 11 percent of the mix, and while he wants that share to grow, reliance on nuclear is, in his words, unavoidable for now. Even the plan to phase out 60 coal plants by 2040 comes with an asterisk, as 20 of them may be kept on as emergency backup.
Korea's dilemma is a sharp version of one now surfacing everywhere. In the UK, 315 data centres are waiting to connect to the grid, a load that would demand an extra 73 gigawatts, nearly twice the country's peak winter demand. In the United States, a banker at BBVA notes, access to reliable power has become as decisive as land or tax breaks in choosing where to build, pulling digital and energy investment into the same calculation. The constraint on the AI boom, in other words, is quietly migrating from silicon to substations.
India may be where the argument gets its most useful framing. Writing in the Economic Times, the head of data-centre firm Sify sets out four questions any host country should answer before the build-out outpaces its grid: whether data centres really use more water and power than comparable industry, whether saving one resource simply burdens another, how efficiency gaps against cold-climate rivals get closed, and whether the load crowds out homes and local businesses. His own answer is cautiously optimistic, arguing that well-planned clusters connected through dedicated substations and backed by new renewable contracts can strengthen a grid rather than drain it. But the underlying warning is universal. Growth, he writes, cannot be an excuse for careless resource use, and a country that gets the arithmetic wrong may find the next generation of technology was built somewhere else.