A Fallen Power Line Exposes the Growing Data Center Problem: How to Solve It

A power line went down outside Washington, D.C., causing over 3 gigawatts of data center load to vanish from the PJM grid in about 30 seconds as data centers switched to backup power. The sudden drop led to a voltage spike that flickered lights across the region, though no blackout occurred. PJM, the largest U.S. grid operator serving 67 million customers, saw the disconnected load reach 3.49 GW at its peak, and it took 11 minutes to stabilize. Experts note that such events are happening more often; a similar incident in 2024 involved 60 data centers disconnecting 1.5 GW. Northern Virginia, within PJM's territory, hosts the world's highest concentration of data centers. Ali Zain Banatwala of the Independent Electricity System Operator suggested that data centers should be programmed to disconnect and reconnect sequentially rather than simultaneously. ON.Energy, a startup, has developed an uninterruptible power supply system that uses batteries and power conversion equipment to hide the data center's variable load from the grid, allowing it to absorb fluctuations and ride through disruptions. The company is installing 3 GW of its systems at four data center campuses. Grid managers like ERCOT are also beginning to require large loads to 'ride through' disruptions. Data centers currently account for about 6% of PJM's load, but are expected to reach 24% by 2040, making the problem more urgent.