The president of Spain’s national electricity grid, Red Eléctrica, has said the outage that blacked out most of the country and neighbouring Portugal on Monday was not a company error and promised it “won’t happen again”.
Speaking to Spanish media, Beatriz Corredor denied the blackout was connected to renewable energy and defended the robustness of Spain’s electricity system, which she called the “best and most resilient in Europe.”
“Relating Monday’s serious incident to the spike in renewables is not correct,” she said.
Corredor also ruled out the theory that a cyberattack caused the power outage but confirmed that Spain’s High Court was still pursuing it as a possibility as part of its investigation.
“I’d like to highlight how quickly the restoration process was completed,” Corredor said.
“By 4 am, we already had 100% of the substations back online. The best minds in the electrical world are in this building. And it was a feat never seen before.”
She said the company was still investigating the cause and that the government has given the grid operator until later on Wednesday afternoon to report their findings.
Corredor maintained “we have done a good job” but cautioned that “zero risk does not exist.”
Meanwhile, Portugal’s National Authority for Emergency and Civil Protection (ANEPC) said they “still don’t know the cause of the blackout,” and that its investigation was ongoing.
The agency’s president, José Manuel Moura, told reporters on Wednesday that there were “zero victims” from the power cut on Monday.
What happened on Monday?
Spain and Portugal lost most of their electricity early in the afternoon.
Shortly after 12:30 pm, Spain lost 15 gigawatts of electricity or roughly 60% of demand in the country of 49 million, Prime Minister Pedro Sánchez said.
There had been two significant “disconnection events” — interruptions in power — before the outage, Spain’s electric grid operator Red Eléctrica said.
While the Spanish grid managed to recover from the first event, systems operations director Eduardo Prieto said that the second was more damaging, progressing to the point of interruptions from France’s electrical system and producing “a massive, temporary disconnection.”
About three hours before the outage, power quality sensors in homes in the Madrid area showed warning signs of an unstable grid.
ADVERTISEMENT
There were small fluctuations in voltage around 9:30 am local time, Whisker Labs CEO Bob Marshall said Tuesday.
The Maryland-based software developer has sensors in homes in and around Madrid, testing the technology for use in Europe for home fire prevention and grid monitoring.
Instead of normal, steady voltage, Marshall said the data shows there were oscillations whose frequency and magnitude increased over the next three hours until the grid failed.
Around noon, there was a big jump in the magnitude of the fluctuations, with the voltage measured going up and down by about 15 volts every 1.5 seconds, Marshall said.
“The way I would interpret our data,” Marshall said, “is that the grid is struggling. Something’s wrong. And it’s showing increasing signs of instability.”
What do officials not know?
Authorities in Spain and Portugal still don’t know exactly what caused the fluctuations and eventual power failure.
“There’s a variety of things that usually happen at the same time and it’s very difficult for any event to say ‘this was the root cause,'” said Eamonn Lannoye, managing director at the Electric Power Research Institute.
Lannoye said there was a range of events that can explain grid failures, including that electric grid lines or generators are switched off in some locations for maintenance.
ADVERTISEMENT
“This could be a really complex event, I think it’s fair to say,” Lannoye said.
Why was France partially affected?
Europe’s electric grid is highly connected, meaning that it can pool power between countries.
That can make the system more resilient, experts say.
But it also means a disruption in a major transmission artery or frequency imbalance can trigger cascading protective shutdowns across countries, according to Shreenithi Lakshmi Narasimhan, a member of the Institute of Electrical and Electronics Engineers.
Spain and Portugal are connected to Europe’s main electric grid through France.
Spain’s grid operator said that the sudden drop in power caused an interconnector between Spain and France to trip.
