AI
The US Grid’s Scale and What Actually Brings It Down
The US grid connects 3,000 utilities, 26,000 generators, and roughly 500,000 miles of transmission line. By global standards, it is reliable. What actually takes it down: a woman climbed a transformer and 800 homes lost power because crews chose not to electrocute her; copper thieves; squirrels; a bird dropping a fish onto a power line. The US has never had a domestic cyber attack cause a blackout. Not once. Misinformation follows every outage anyway, including a Texas event that generated reports of a “surprise sunset.”
The Iberian Blackout: A Physics Failure Misread as a Cyber Attack
On April 28, Spain and Portugal lost power in roughly 2 minutes. Within hours, LinkedIn and Twitter filled with “probably a cyber attack” posts, some tied to product pitches. The actual sequence: a dispatch error in the morning left generators under-deployed. Voltage fluctuated; residential solar tripped on high-voltage warnings. Oscillations grew. France disconnected one interconnect to protect itself and damp the instability. Damping failed without properly deployed generators. Oscillations amplified. Nuclear plants scrammed. Protection relays cascaded across the country, and by 12:34 the grid was dark.
Sixteen Hours to Recovery and What the Communication Failure Cost
Spain’s black start went well. Crews started rebuilding the grid at 1:30 p.m. using black-start plants, generators that spin up without external power, reconnecting sections one at a time. By 4:00 a.m. on April 29, everyone had power back: 16 hours total. Texas took longer in comparison. The failure was communication. Cyber-attack rumors caused residents to drain stores, convinced the outage would last days. Stewart contrasted Spain with a South Carolina utility whose CEO publicly narrated the restoration step by step, turning a crisis into a community effort.
Real Vulnerabilities Buried Under FUD
The FUD cycle is measurable. Around DEF CON, Black Hat, and BSides, 17 news stories ran the same arc: vulnerability found, grid could collapse, buy the product. That cycle pulled asset owners away from actual findings. Mandiant published relay vulnerability research that most operators missed because they were fielding calls about “rogue Chinese inverters.” Those inverters contain a “kill switch,” which the press uses instead of the correct term: a rapid shutdown device required by the National Electric Code. Actual threats need focused attention. Misinformation consumes the capacity to act on them.
Notable Quotes
Squirrels are still one of the leading causes of our power going out. Emma Stewart · ▶ 3:38
It made it sound way more dramatic when you call it a kill switch than a rapid shutdown device that’s required by the National Electric Code. Emma Stewart · ▶ 16:08
turning off the grid is a is a defense mechanism Emma Stewart · ▶ 17:40
Key Takeaways
- The US grid has never been taken down by a domestic cyber attack. Physics and animals remain the primary culprits.
- Spain’s April 2025 blackout resulted from a dispatch error and oscillation cascade, recovered in 16 hours.
- Fear-based media narratives about grid cyber attacks distract asset owners from vulnerabilities that actually require action.
About the Speaker(s)
Emma Stewart is Chief Scientist for Power Grid at Idaho National Laboratory, where she leads supply chain consequence analysis for digital assurance in energy storage and system-level programs. She holds a Ph.D. in Electrical Engineering and an M.Eng. in Electrical and Mechanical Engineering, and has spent 20 years in power systems across multiple countries. Her work includes incident response for the electric grid, patents for innovations in power distribution systems, and training and R&D services for electric cooperatives spanning energy integration, resilience, grid planning, and microgrid technologies.