Spain, Portugal switch back on after biggest blackout

Otago Daily Times

29-04-2025

Spain and Portugal have switched their power back on after the worst blackout in their history, though authorities offered little explanation for what had caused it or how they would prevent it happening again.
Traffic lights were back on, train and metro services slowly returned and schools reopened. Commuters battled with delays to get back to work after an outage that had left people stranded in lifts and cut off from phone contact with their families.
The sudden outage had seen the equivalent of 60% of demand in Spain drop in five seconds around midday on Monday (local time).
While Spanish grid operator REE on Tuesday ruled out a cyber attack as the cause, Spain's High Court said it would investigate whether the country's energy infrastructure had suffered a terrorist strike and Prime Minister Pedro Sanchez said his government had not ruled out any hypothesis.
"We must not rush to (conclusions) and (commit) errors through haste. We will find out what happened in those five seconds."
REE said it had identified two incidents of power generation loss, probably from solar plants, in Spain's southwest that caused instability in the electric system and led to a breakdown of its interconnection with France.
Spain is one of Europe's biggest producers of renewable energy, and the blackout sparked debate about whether the volatility of supply from solar or wind made its power systems more vulnerable.
Redeia, which owns Red Electrica, warned in February this year in its annual report that it faced a risk of "disconnections due to the high penetration of renewables without the technical capacities necessary for an adequate response in the face of disturbances".
Investment bank RBC said the economic cost of the blackout could range between €2.25 billion and €4.5 billion ($NZ4.3 billion and $NZ8.6 billion), blaming the Spanish government for being too complacent about infrastructure in a system dependent on solar power with little battery storage.
SEAT said power returned to its Barcelona car plant at 1am on Tuesday but that it still wasn't at full production.
Volkswagen said its plant in Navarra lost a day of production - equivalent to 1400 cars - as it was not able to restart until 2.30pm on Tuesday. State of emergency
Javier Diaz, a 24-year-old student, was forced to sleep in music venue Madrid's Movistar Arena after finding himself stranded in the capital. Luckily, he had just finished walking the Camino de Santiago, a Christian pilgrimage route in northern Spain, and had a sleeping bag, "so we had quite a good night".
Madrid authorities put on free buses to get people to work on Tuesday and the metro and some trains resumed operating, although with delays. Construction worker William Galicia, 39, had seen three buses pass by completely full.
"We'll have to be lucky for one with a bit more space inside so we can get in," he said.
A state of emergency was declared across many Spanish regions on Monday, with the deployment of 30,000 police. In Atocha station in Madrid, police and Red Cross workers handed out blankets and bottles of water.
Three people died from suspected carbon monoxide poisoning in the northwestern region of Galicia after switching on a generator to power an oxygen machine for one of the victims, regional emergency services said.
Bars and restaurants counted the cost of lost produce after fridges and freezers were switched off for more than eight hours.
"(We're) scared it will go bad, that we have to throw everything away. We don't know if the insurance will cover it," said Maria Luisa Pinol, 63, owner of the Granja Isabel bar in Barcelona, which had to shut on Monday night.
In Portugal, the government said hospitals were back up and running, airports were operational albeit with delays in Lisbon, while the capital's metro was restarting operations and trains were running.
Carlos Cagigal, an energy expert, said the outage probably happened because Spain's nuclear plants weren't operating at the time, meaning all of its electricity was coming from renewable sources that were feeding saturated substations.
When one of those substations failed and there wasn't adequate backup, safety protocols kicked in and the system disconnected, he said.
"Given these system imbalances... there is a small margin of risk of this happening again," he said.
Alberto Nunez Feijoo, leader of the opposition conservative People's Party, said the government should rethink its plan to shutter nuclear plants.
But on Tuesday, Sanchez ruled out an excess of renewable energy as a cause of the network's collapse.
He said Spain's nuclear power stations still hadn't resumed operating on Tuesday, which he said showed they were no more resilient than renewables.
Demand at the time of the blackout was relatively low and that there was ample supply, he said.
"What happened yesterday was an exceptional event in normal, everyday circumstances." What causes outages?
The most common cause of an unplanned power cut which disables electricity on a large scale is extreme weather such as storms, lightning strikes or high winds. The weather at the time of Monday's collapse was fair.
Power outages can also happen when there are faults at power stations, power distribution lines, substations or other parts of the system.
Electricity flow between systems in Europe is maintained at 50 Hertz (Hz) to ensure stability. If that level varies, backup systems disconnect assets such as power generation sources from the grid to protect them from damage.
Red Electrica said it had identified two incidents of power generation loss, probably from solar plants, in southwestern Spain that caused instability in the electric system and led to a breakdown of its interconnection with France. The electrical system collapsed, affecting both the Spanish and Portuguese systems.
Spain was exporting power to France and Portugal at the time of the outage. Exports to France were close to the available net export capacity until 10am (local time). According to Red Electrica data, exports to France stopped at 12.35pm (local time) from 868 MW beforehand.
The Spanish grid is interconnected with those of France, Portugal, Morocco and Andorra.
The process of restoring power after a major cut is known as a "black start". It involves gradually restarting power plants individually and reconnecting them to the grid.
As Spain tried to get more power back on Monday it turned more gas and hydropower plants online and increased power imports from France and Morocco.