What do we know about the Great Blackout in Spain and Portugal?

The blackout that affected Spain and Portugal last Monday has been described as one of the worst in Europe, interrupting essential services for tens of millions of people.

At 12:30 p.m. local time, Spain lost approximately 15 gigawatts of electricity, which represents about 60% of the country’s demand, according to Prime Minister Pedro Sánchez.

The authorities are still investigating the causes of the blackout, which left a large part of the Iberian Peninsula without electricity since Monday afternoon.

Intermittent signals preceded the worst power outage in Europe in years

The operator of Spain’s electrical grid, Red Eléctrica de España, reported that two significant disconnection events had occurred before the blackout, with the second being the most damaging, causing interruptions from the French electrical system.

Additionally, sensors in homes in Madrid detected fluctuations in voltage hours before the blackout, suggesting problems in the electrical grid. These oscillations increased in frequency and magnitude, leading to a preliminary conclusion that the grid was experiencing instability. However, the exact root of the problem is still unknown.

The Supreme Court of Spain has initiated an investigation to clarify the causes, initially ruling out a possible cyberattack. Energy experts have pointed out that the high generation of renewable energy in Spain could have influenced the network’s vulnerability to fluctuations.

Although Spain is a leader in solar and wind energy, this raises questions about whether this dependence may have made the national electrical grid more susceptible to interruptions of this kind.

The interconnection of the electrical grid of Spain and Portugal with the rest of Europe through France plays a key role in the spread of problems. The system is designed to operate cooperatively, but a significant failure can trigger cascading blackouts in neighboring countries.