Spanish competition authorities have launched an independent investigation into the massive power outage that plunged the Iberian Peninsula into darkness on April 28, 2025, citing the need for technical scrutiny separate from other ongoing probes.
The Spanish National Commission on Markets and Competition (CNMC) announced on May 13, 2025, that it had opened formal proceedings to examine both the causes of the blackout and the process used to restore electricity across Spain and Portugal.
According to CNMC President Cani Fernández, who testified before Parliament, the regulator will focus not only on identifying the root causes of the incident — which remain unknown — but likewise on assessing whether specific errors occurred during the system restart that could have worsened or prolonged the disruption.
The CNMC emphasized its role as an independent technical body, stating it would bring specialized expertise to complement investigations already underway by Spain’s Ministry for Ecological Transition, the European Network of Transmission System Operators for Electricity (ENTSO-E), and a judicial probe examining potential cyber sabotage.
Officials reported that approximately 15 gigawatts of power — equivalent to 60% of Spain’s total electricity consumption — vanished within seconds during the April 28 event, triggering a cascading failure that collapsed the entire Iberian grid in just 27 seconds.
ENTSO-E’s preliminary analysis indicated the outage began at 12:33 p.m. Local time with the instantaneous loss of 2.2 gigawatts — roughly the output of two nuclear reactors — setting off the chain reaction that led to the widespread blackout.
While hypotheses including a cyberattack or solar power overproduction have been discussed, grid operator Red Eléctrica de España has deemed a cyber intrusion unlikely, and no definitive cause has been established.
The CNMC confirmed it has already begun requesting technical data from energy companies operating in the region as part of its fact-finding effort, which will run parallel to other official inquiries into one of Europe’s most significant power failures in recent years.
