The report by European experts concludes regarding the massive blackout: "There were multiple factors."

BrusselsFinal report by European experts on the major blackout in the Iberian Peninsula. Almost a year after the incident, a study by the European Network of Transmission System Operators (ENTSO-E) concluded that the blackout of April 28th of last year was due to "multiple interconnected factors," including "cascade generators" and "overvoltages." The report, which involved 45 experts, reiterates that voltage is the energy level and must be maintained within certain limits. In this regard, they point out that a classic cause of a blackout is a voltage drop due to an imbalance between supply and demand. In the case of the major blackout, the reason for this imbalance was multifactorial, according to the study released this Friday by the European body. The European body's investigation indicates that the incident occurred in a matter of seconds after a rapid increase in voltage in the Iberian electrical system, which led to a chain reaction of power plant shutdowns, particularly those in the Iberian Peninsula. of renewables. "They operated with a fixed power factor and did not react to voltage changes," the report says.

The progressive loss of production also caused a drop in frequency and a loss of synchronization with the rest of the European electricity grid, which ultimately led to the total collapse of the electricity supply in Spain and Portugal.

In this regard, they reject linking the incident to a single technology and assert that "it is not a problem with renewables, but with voltage control," although they point out that some of the green generation did not react dynamically to the system changes. Furthermore, the report confirms that the system's defense mechanisms were activated automatically, as planned, but that this was insufficient to stop the chain of errors and, therefore, to prevent the blackout last spring. However, the report in no way blames renewable energies or any specific energy generation technology, but rather voltage control and other factors already mentioned. The study also describes the power outage that affected Spain and Portugal on April 28, 2025, as "the most serious and unprecedented incident in the European electricity system in more than 20 years." "All the contributing factors were also exceptional in terms of their complexity, scope, and the nature of the events," the experts admit.

La Moncloa agrees with the European study

At Moncloa Palace, officials asserted that the European study "coincides" with the report presented last year by the Spanish government's analysis committee, which also identified a multifactorial "origin" for the massive blackout. "The document underscores that the cascading blackout that culminated in a total power outage was not caused by a lack of inertia in synchronous generators, nor by the high penetration of renewable energy generation, but by a complex combination of factors and circumstances that can be prevented through technically available solutions," the Spanish government stated.