A Blackout Shuts Down Spain and Portugal

At 12:33 CEST on 28 April 2025, the electrical network across peninsular Spain and mainland Portugal experienced a sudden and total breakdown. Operating reserves had seemed ample minutes beforehand, with Spanish generation delivering thirty-two gigawatts against a domestic demand of twenty-five gigawatts while exporting power across borders. However, low-frequency oscillations in the transmission system had emerged earlier that hour. When generation trips struck southern substations near Granada, Badajoz, and Seville within seconds of each other, electrical frequency plummeted, voltage surged unpredictably, and protective safeguards severed the interconnectors tying the peninsula to the wider European network.

The complete decoupling caused thirty-one gigawatts of load to drop offline almost instantaneously. In Spain, all high-speed and commuter rail operations ground to a halt, leaving approximately thirty-five thousand passengers stranded across train carriages and subterranean transit routes. Subways ceased running, international air terminals shifted to emergency backups or curtailed flights, and city traffic descended into congestion as traffic signals failed. Backup generators kicked in to supply critical cooling systems at four operating nuclear reactors, while hospitals relied on auxiliary engines to sustain vital care.