On April 29, 2025, the aftermath of a massive power outage that struck Spain and Portugal the day before continued to raise questions, as authorities struggled to determine the cause of the blackout that left millions in the dark. The incident, which began on April 28 at approximately 12:33 PM local time, resulted in a substantial loss of electricity, with Spain losing 15 gigawatts—equivalent to 60% of its national demand—in a matter of seconds.
The blackout, one of the most severe in European history, paralyzed flights, disrupted metro networks, and caused widespread communication failures across the Iberian Peninsula. By Tuesday morning, the electrical supply had been largely restored, with the Spanish operator Red Eléctrica reporting normal operations by 11:00 AM, while its Portuguese counterpart, REN, confirmed that power had been restored to 6.4 million customers.
Despite the restoration of service, the cause of the outage remained unclear, prompting investigations from both Spanish and Portuguese authorities. Spanish President Pedro Sánchez stated that the government was prioritizing the restoration of electricity and identifying the reasons behind the blackout. "We will take the necessary measures to ensure this does not happen again," he said during a press conference.
Authorities are also looking into five fatalities that may be linked to the blackout. Reports from the Spanish news agency EFE revealed that three members of a family in Galicia died from suspected carbon monoxide poisoning after using a generator to power a respirator. Additionally, a woman in Valencia died due to complications from an oxygen machine that failed during the outage, and a fire caused by a candle in Madrid claimed the life of another person.
Eduardo Prieto, director of operations at Red Eléctrica, noted that two significant disconnection events occurred just before the blackout, but further investigation is needed to understand their connection to the outage. Spain's meteorological agency, AEMET, found no unusual weather phenomena that could have contributed, and the National Cybersecurity Center of Portugal ruled out a cyberattack. Teresa Ribera, executive vice president of the European Commission, also dismissed sabotage as a possible cause.
As the investigation continues, the impact of the blackout was felt across various sectors. The Madrid Open tennis tournament resumed after 22 matches were postponed due to the outage, while train services began to recover, although some commuter trains remained suspended due to voltage instability. Emergency workers managed to rescue around 35,000 passengers stranded on railway and underground lines.
Witness accounts painted a chaotic picture of the situation. Rubén Carrión, a 24-year-old who was stranded on a commuter train, described his experience as "pure chaos." Many travelers spent the night in train stations, wrapped in blankets provided by the Red Cross, waiting for updates on their journeys.
The blackout not only disrupted daily life but also raised concerns about the stability of Spain's electrical grid. Experts pointed out that the increasing reliance on renewable energy sources could have played a role in the outage. Spain has set ambitious goals to source 81% of its electricity from clean energy by 2030, with renewables accounting for 66% of installed capacity by the end of 2024.
However, the lack of inertia in renewable energy systems, which rely on electronic inverters, could compromise grid stability during sudden demand changes. Miguel de Simón Martín, an electrical engineering professor at the University of León, noted that the blackout occurred because the system could not balance the sudden loss of generation capacity, leading to an automatic disconnection to protect the grid.
To prevent future outages, experts recommend measures such as limiting solar energy production during low demand periods and enhancing electrical interconnections with neighboring countries. Sánchez confirmed that the government would investigate the incident thoroughly, reviewing records from Red Eléctrica and private operators.
As the European Commission prepares an independent report on the blackout, which will include a technical assessment expected within six months, the focus remains on ensuring that such a disruption does not occur again. The incident serves as a stark reminder of the vulnerabilities in modern electrical infrastructure and the need for robust systems to manage the complexities of energy production and consumption.
The events of April 28 have left the people of Spain and Portugal grappling with the implications of the blackout, as they seek answers and reassurance that their power supply will remain stable in the future.
