For the first time in its 75-year history, the Statistical Review of World Energy this year gave data centers a line of their own, and the figure is startling. Global data-center electricity demand hit 787.8 terawatt-hours in 2025, up almost 20 percent in a single year and nearly double what it was in 2020. Treated as a country, the world's data centers would rank among its largest power markets. The United States alone consumed close to 40 percent of that total and accounted for roughly half of last year's global increase. After two decades in which American electricity demand barely moved, the flat line has bent sharply upward, and utilities agree on the culprit.
That much is now familiar. What this week's reporting sharpened is the question that follows the megawatts: who pays to move them. Building the servers is the easy part. The electricity has to travel through transmission lines, transformers and substations, much of it built in the 1960s and 70s and now near the end of its life. A new US National Transmission Needs Study estimates that roughly 4,000 miles of power line will have to be replaced every year for decades. In the first half of 2026, transmission congestion costs across the PJM grid jumped 43 percent to $6 billion, with data-center-heavy Northern Virginia among the worst-constrained corridors.
Someone has to fund all of that steel and copper, and consumer advocates worry it will be ordinary households. "We feel like the transmission element is something that largely gets glossed over, but it's a huge cost that ultimately is borne by ratepayers," says Geoff Marke, chief economist at Missouri's Office of Public Counsel. The political answer so far has been the promise. The Trump administration is pointing to a voluntary ratepayer-protection pledge, signed by tech companies, utilities and governors, whose principle, as one Energy Department official put it, is that "the data centers will pay for the infrastructure upgrades for their generation, not the families." States such as Missouri have gone further and written consumer protections into law.
Whether a voluntary pledge holds when the invoices arrive is the open question, and there is reason for caution. A group of nine transmission utilities, including Ameren and Evergy, is asking federal regulators for a right of first refusal to build major new lines, which would pause competitive bidding. Marke's objection is blunt: competition "reigns in overspending," and handing incumbents a guaranteed franchise tends to inflate the very costs that land on customer bills. The people promising that families will be shielded and the people positioned to profit from the buildout are, in places, the same utilities.
Australia this week showed how quickly the principles can bend under pressure. Canberra had planned to require new data centers to run on renewables backed by batteries and gas, pay for their own grid upgrades, and avoid pushing up household bills. At Wednesday's National Cabinet, the federal government softened that stance, and standards due to be legislated in early 2027 will now leave room for Queensland and the Northern Territory to power data centers with coal and gas. Regulators there expect these facilities to reach 13 percent of national grid demand by the mid-2030s, up from 3 percent today. The clean-energy condition was one of the first things to give way.
The lesson running through all of it is that the AI boom's hardest constraint may sit outside the data center, in a grid that was never designed to grow this fast. Chips can be ordered and campuses can be poured in months; a major transmission line takes years to permit and build. The countries and states racing to host AI are discovering that the technology's real footprint is physical, expensive and slow, and that the fight over who carries that cost, the companies profiting from the compute or the households already paying the light bill, is only beginning.