Power outage in Spain and Portugal: what caused it and was there a cyberattack?

Several countries in Europe have struggled to restore electricity after a major power outage caused blackouts, The Guardian reports.

Spain, Portugal and parts of southwestern France suffered a massive power outage on Monday, with major cities including Madrid, Barcelona and Lisbon among those affected.

Homes, offices, trains, traffic lights and even the Madrid Open tennis tournament were hit, causing chaos for millions of people and prompting an effort by the Spanish and Portuguese governments and network operators to understand the problem and solve it.

What happened?

Red Eléctrica de España (REE), Spain's electricity grid, said Spain and Portugal were hit by "el cero" - zero.

Its Portuguese counterpart, Redes Energéticas Nacionais (REN), said the outage began at 11:33 a.m. Western European time.

By mid-afternoon, the Spanish operator, which is partly state-owned, said it had begun to restore voltage in the north, south and west of the Iberian peninsula.

The recovery process could only be carried out gradually, to avoid overloading parts of the grid as each generator connects.

Endesa, Spain's largest energy company with 10 million customers, and Iberdrola, the second largest provider, said they were working with REE in accordance with established protocols.

What caused it?

Portuguese Prime Minister Luís Montenegro said the problem originated in Spain. Portugal's REN said a "rare atmospheric phenomenon" had caused a severe temperature imbalance that led to widespread shutdowns.

"Due to extreme temperature changes in the interior of Spain, there were abnormal oscillations in very high voltage lines (400 kV), a phenomenon known as 'induced atmospheric vibration'. These oscillations caused synchronization failures between electrical systems, leading to successive disturbances across the interconnected European grid," REN said.

The dangers posed to electrical systems by large changes in atmospheric temperatures are well known in the industry, even if it is rare for problems to occur on this scale.

"Due to the temperature change, the conductor parameters change slightly. This creates an imbalance in frequency," said Taco Engelaar, managing director at Neara, a software provider for energy services.

Georg Zachmann, a senior fellow at Bruegel, a research organization in Brussels, said the system had suffered "successive power plant outages" - including one in France - when the grid frequency dropped below the European standard of 50Hz.

Could it have been some foul play?

European Council President António Costa, who was Portugal's prime minister from 2015 to 2024, said there was "no evidence that it was a cyberattack" but warned that the ultimate cause was still unclear.

European Commission Senior Vice President Teresa Ribera also told Spain's Radio 5 that there was no evidence that a deliberate act had caused the outage.

However, Spain's national security council met on Monday to assess the outage. Portugal's prime minister said it was too early to say for sure what caused the outage.

What is the role of renewable resources?

Spain is on its way to becoming a leader in green energy: it has abundant sun and wind. Last year was a record period for renewable energy production, which accounted for 56% of all electricity used. By 2030, this percentage will increase to 81.

This change will help Spain wean itself off its dependence on energy imports, but it also brings its own challenges. Every national grid in the world will have to spend heavily to improve distribution systems, connect distributed renewable generation, and ensure it is balanced.

What is network balancing?

The grid needs constant management to ensure it is not overloaded by too much generation, or shorted by too little. Power stations will automatically shut down if the frequency falls outside the normal range. To restart, they must be reconnected to users.

Balancing has been important for as long as there has been a grid, but there is more attention on the issue due to the rapid shift to renewable sources like solar and wind, which are intermittent.

Rotary gas turbines have been the standard technology for frequency management for decades, but renewables will require investments in other options such as flywheels or advanced power electronics.

"You can't ignore it. You need the tools to keep the system running," Zachmann said.

Did international connections cause problems?

Engelaar said such a widespread failure was “extremely unusual.” However, there have been previous examples.

In 2003, a problem with a hydroelectric line between Italy and Switzerland caused a major outage across Italy for about 12 hours.

A power outage in Germany in 2006 caused outages as far away as Portugal and Morocco.

"Connectivity between countries is vital for sharing clean energy, but it also creates new pathways for the rapid spread of failure," Engelaar said.

However, Bruegel's Zachmann said the interconnections also help prevent the problems from getting worse. The connection with France will make it "much easier to restore the electricity system."

"Yes, problems spread, but at the same time the larger system acts as a buffer and prevents the crisis from escalating," he said. /Telegraph/