What Caused the European Power Outage?

There’s still no official explanation for the blackout in Spain, Portugal, and parts of southern France—but experts point to the makeup of the Iberian peninsula’s power grid.

The causes of the power outage that left millions in Spain and Portugal without electricity on Monday have yet to be fully determined, though service has now been restored across 99 percent of the Iberian peninsula. Red Eléctrica, the public company in charge of operating Spain’s transmission infrastructure, has preliminarily ruled out a cyberattack, human error, or unusual weather or atmospheric conditions as a cause of the outage. The company points out that the incident could have originated from two “disconnections of generation,” possibly linked to the inherent volatility of renewable sources.