Data centers used to need protection from grid disturbances. They still do. However, the scale of the latest AI data centers has reversed the equation. Now the grid needs to be safeguarded from problems caused by AI data centers.

A downed power line that generated a brief voltage disturbance near Washington, D.C. caused 3.8 GW of data centers to revert to on‑site backup power within seconds. This represented about 3% of demand and caused lights to flicker as far away as Chicago.

The system operator (PJM Interconnect) scrambled and restored stability within about ten minutes. Similar events occurred in 2024 and 2005 in Virginia after scores of data centers tripped off the grid and reverted to backup generation.

That’s just one way data centers can suddenly cause grid destabilization. Large AI factories suffer from massive swings in power use. They can surge up and down – sometimes from 1 GW to almost nothing and back again several times a second in extreme cases.

If not properly managed, rapid changes in demand can contribute to voltage or frequency disturbances, potentially affecting grid reliability and sensitive equipment.