Investigating the Cause of a Widespread Power Outage in Iberia

Sat Sep 13 2025 18:43:03 GMT+0300 (Eastern European Summer Time)

Spain's grid operator has ruled out cyber interference, but the mystery behind the massive power cut affecting Spain, Portugal, and parts of France remains unresolved.

Spain's grid operator, Red Eléctrica, confirmed that a recent extensive power outage was not due to a cyber attack but has yet to identify the exact cause. Experts speculate that several factors could have contributed, including issues with renewable energy supply and the country's reliance on limited power connections to France.

On Monday, a significant power outage struck Spain, Portugal, and sections of France, leading the Spanish grid operator, Red Eléctrica, to eliminate the possibility of a cyber attack as the cause. Its operations director, Eduardo Prieto, indicated that preliminary investigations found no interference with control systems, a sentiment echoed by Portuguese Prime Minister Luís Montenegro. However, the exact cause of the outage remains unknown, and the operator stated that no conclusions could be drawn until more detailed data emerges.

Spanish Prime Minister Pedro Sánchez emphasized that investigators are actively seeking to determine the source of the outage, promising to implement measures to prevent future occurrences. Initial reports suggest the cut may have stemmed from a sudden loss of 15GW of power, which corresponds to 60% of the demand at that moment. Prieto mentioned that there were two notable disconnection events located in southwest Spain, an area with substantial solar energy production.

Discussions are ongoing regarding whether the outage could be linked to renewable energy systems. While Sánchez dismissed the idea that excess renewable energy was to blame, he acknowledged that temporary disconnections often occur when the electricity supply does not match demand. Experts explain that significant discrepancies in the frequency of electrical supply can force companies to offline their systems as a protective measure; this domino effect can lead to widespread blackouts.

With renewable energy dependent on weather conditions, some experts noted it was surprising such a scenario hadn't been predicted. The potential implications of Spain's connection to France have also come under scrutiny, as it utilizes a high voltage direct current line for interconnection. This limited connectivity sometimes renders the Iberian Peninsula prone to disruptions.

In addition to these technical concerns, a previously mentioned theory suggesting that a rare atmospheric event led to oscillations in high voltage lines was refuted by Portugal's grid operator, clarifying that they never issued such a statement. As recovery efforts continue, experts are urging a closer examination of the electricity supply system's vulnerabilities to ensure stability in the future.