Northern Virginia data-center load transferred to backup on one normally cleared 230 kV Ashburn fault, in two waves (PJM load 99,984 to 96,205 MW, a 3.8% fall), the largest such event in PJM's history; PJM reported no significant reliability impacts. PJM proposed large-load voltage and frequency ride-through requirements on 2026-09-08 and plans to file at FERC in November 2026
~3.8 GW (2026-07-22)observed
| Value kind | observed — Reported measurements, counts, and specifications keep the precision and scope stated by their source; an exact specification is not treated as a range. |
|---|---|
| Scope | About 2.5 times the roughly 1,500 MW sequence total of the July 2024 event (3,779 MW net system-load fall against about 1,500 MW). The July 2024 sustained loss was about 1,260 MW. |
| As of | 2026-07-22 |
| Source | PJM, Inside Lines (2026-08-11, event review; 2026-09-10, ride-through proposal) |
| Review | checking…review by 2026-12-15 · standard cadence |
| Recorded changes | last 2026-10-13 · 2 revisions tracked |
| Claim id | pjm-ashburn-2026-data-center-load-drop |
Where the guide uses it
- 4.10 Grid-Interactive Behavior: Ride-Through, Reactive/Voltage Support & Frequency Response Toward the POI
- 13.10 Staged Power/Load Ramp, Go-Live & Handover to Operations
- 14.13 Agentic Ops, RL Control & the Autonomy Ladder
← Full numbers register — every date-stamped figure in the guide, with revision history.