A Fallen Power Line Exposed AI Data Centers’ Grid Problem

A fallen power line outside Washington, DC, triggered a grid event that normally would have taken seconds to recover from. Instead, recovery took more than 10 minutes after more than 3 gigawatts of data center load stopped drawing power nearly simultaneously.

The event did not cause a blackout, but it did cause lights to flicker across the region. TechCrunch reports that voltage spikes were observed across the PJM grid from Northern Virginia to Chicago.

Electrical grids need supply and demand to stay closely balanced. When data centers sensed the voltage dip, many switched to backup power within seconds, removing large amounts of demand from the grid at once.

That rapid disconnection turned a supply-side disruption into a larger demand-side shock. At its peak, PJM had an extra 3.49 gigawatts of electricity on the grid before it stabilized.

One proposed fix is to prevent nearby large loads from disconnecting or reconnecting all at once. A more orderly sequence would give grid operators more predictable conditions and better tools for responding to disruptions.

Another approach is to build data centers that can absorb grid disturbances rather than immediately switching away from the grid. TechCrunch highlights ON.Energy’s campus-scale uninterruptible power supply, which uses batteries and power conversion equipment to present the grid with a steadier load.

Northern Virginia is home to the world’s highest concentration of data centers, and it sits inside PJM’s territory. PJM manages grids from New Jersey to Illinois and serves 67 million customers, making it the largest grid operator in the United States.

The latest mass disconnection was twice as large as a similar 2024 event, when 60 data centers disconnected and pulled 1.5 gigawatts of load from the grid. TechCrunch reports that data centers accounted for about 6% of PJM’s load then and are expected to make up 24% by 2040, underscoring the need for stronger grid-response standards.