Millions across Spain and Portugal faced chaos on Monday after a massive power outage plunged the Iberian Peninsula into darkness.
Electricity supplies are slowly returning to some regions, although many people still face a difficult night without power or services.
The outage disrupted everyday life, halting trains, cutting phone and internet connections, and disabling traffic lights and ATMs across both countries.
Some parts of southern France were also impacted by the disturbance, adding to the regional confusion and uncertainty on Monday afternoon.
Spain’s national grid operator, Red Eléctrica, said power was restored in areas like Catalonia, Andalusia, the Basque Country and Castile and León.
Eduardo Prieto, head of operations at Red Eléctrica, described the incident as “exceptional and extraordinary,” highlighting its unprecedented nature.
European Commission vice president Teresa Ribera called the event “one of the most serious episodes recorded in Europe in recent times.”
Experts suggested several possible causes, but no definitive explanation has been confirmed by authorities at this stage of the investigation.
One theory mentioned a rare “induced atmospheric vibration” causing anomalies in the region’s high-voltage lines and disrupting synchronisation.
Professor Solomon Brown explained that such phenomena could destabilise electrical power flows, much like solar events sometimes do.
Other experts warned that interconnected grids might have allowed a small fault to cascade into a much larger regional problem.
Portuguese officials mentioned technical issues but ruled out a cyberattack, despite earlier speculation by some political leaders.
Authorities are urging patience as technicians work to restore full service and investigate exactly what caused Monday’s blackout.
