America's largest grid asks permission to switch data centres off first

PJM's FERC filing would register loads above 50 MW and curtail those that cannot bring their own capacity, starting June 2027.

PJM, the grid operator serving about 67 million people across 13 states, has filed two proposals with federal regulators. The first, an Interim Resource Adequacy Service, would create a registry of large loads of at least 50 MW and require them to bring their own new capacity. From June 2027, a data centre that cannot demonstrate it has secured capacity would be subject to curtailment before pre-emergency load management measures are deployed — that is, it gets switched off before anyone else is asked to cut back. The second is a reliability backstop auction to cover a 6.8 GW shortfall from the last base capacity auction.

The numbers behind it: PJM forecasts 30 to 34 GW of new large-load demand by the early 2030s and as much as 70 GW by 2038. Its June capacity auction cleared at a record $16.4 billion, roughly eight times pre-2024 levels. About 55 GW of solar, battery, wind and gas has cleared the interconnection queue.

This is carded as friction, and the eight-times figure is why. Capacity cost is not an abstraction: it flows to everyone connected to the grid, including households who did not build a data centre. When the largest US grid region formally contemplates rationing its biggest new customers, the constraint has moved from generation to delivery, and the cost of that constraint is being socialised.

Read with today's Texas card, two major grid regions moved within days toward rationing rather than building. The filing is not approved, and critics quoted argue it shifts the burden to states rather than making data centres pay directly.

Source: Canary Media