Electric service was almost completely restored on Tuesday in Spain and Portugal after the unusual and large-scale blackout that plunged both countries into a day of disorder and confusion.
On Monday, April 28, the Iberian Peninsula experienced a severe power failure whose causes remain unknown. Although electricity has returned, the effects of the most serious energy collapse in years are still being felt.
In Madrid, citizens celebrated the return of power with applause and cheers after hours without electricity, internet, or access to mobile phones. At 6:00 a.m. local time, Red Eléctrica de España (REE) announced that 99.16% of the supply had been restored.
Portugal Regains Electrical Stability
In Portuguese territory, operator REN reported on Tuesday morning that the grid was operating “with full stability.” It also noted that the healthcare system was “normalized,” trains were “in operation,” and there had been “no security or civil protection issues,” according to a government statement published on X.
The same message stated that all customers — except 800 isolated cases — already had power, and that those remaining users were affected by “an unrelated outage.” Lisbon’s subway began operating again, although some lines still faced delays due to “a specific failure at the data center,” which was already being resolved. Meanwhile, Porto’s subway was running without restrictions.
Spain: Train Routes Resume as Cause Remains Unclear
In Spain, the return of power allowed the resumption of railway traffic on key routes such as Madrid-Barcelona and Madrid-Seville, according to the Renfe company. However, several other lines remained suspended in different parts of the country.
Later that evening, President Pedro Sánchez made a statement from the Palacio de la Moncloa, acknowledging that the reasons behind this unprecedented blackout were still unclear. “No hypothesis is being ruled out,” he said. “We still don’t know what caused the sudden interruption of supply, but experts are working on it,” he assured.
REE Rules Out Cyberattack, Suggests Technical Origin
Spain’s electrical grid operator ruled out on Tuesday that the blackout had been caused by a cyberattack, following an initial review of its systems.
Red Eléctrica de España confirmed that, based on preliminary analysis, “no intrusion into the control systems” was detected that could have triggered the event.
During a press conference, Eduardo Prieto, Director of Operations Services at REE, explained that a “factor compatible with a generation loss” was identified in the southwestern part of the peninsula, although it was successfully managed.
Possible Link to Solar Energy
Just 1.5 seconds later, another event occurred affecting the system’s balance, and within 3.5 seconds, “conditions consistent with the oscillations recorded during the blackout” were generated.
“We can confirm that it was not a cybersecurity incident,” Prieto emphasized, adding that “it is likely that solar generation was involved,” though he stressed that final conclusions are not yet available and asked people to avoid premature speculation.
