Spain has set up a commission to investigate the cause of the power blackout that brought much of the country, and its neighbours, to a standstill.
Spanish Prime Minister Pedro Sanchez said the government had set up a commission to investigate what triggered the incident, and refused to rule out any hypothesis.
Spain's top criminal court on Tuesday said it was also investigating whether the huge blackout that paralysed the Iberian Peninsula was "an act of computer sabotage on critical infrastructure".
Cyber terrorism is among the potential explanations, while the "critical situation" created for the population meant an investigation was necessary, the Audiencia Nacional said in a statement.
Several theories have been put forward – including a cyber attack or weather phenomena – but as yet no cause has been determined for the energy blackout that hit traffic lights, train lines, lifts, phones, the internet and the financial system.
The country had suffered a loss of 15GW of electricity generation in seconds, which is equal to 60 per cent of national demand. The grid instability caused the Spanish and French electricity interconnection through the Pyrenees mountains to split, resulting in a general collapse of the Spanish system.
The power was mostly restored on Tuesday as the country began to return to normal.
Judge Jose Luis Calama, a judge in Spain’s national court, has also demanded that the national cyber agency and the power grid operator present reports on how the blackout across the Iberian Peninsula occurred. He also made a similar request to the national police.
Mr Calama said that while the reasons for the blackout are still unknown “cyber terrorism is among the possibilities” and, therefore, an investigation is needed.
Even though a preliminary assessment from Spanish grid operator REE ruled out a cyber attack, Mr Sanchez said the country's cyber security authorities were conducting a separate investigation on such a possibility.
Mr Sanchez ruled out on Tuesday the possibility that an excess of electricity generated by renewable sources caused the blackout.
He said technicians were still attempting to find the precise cause of the collapse and the results of their enquiries would be used to reinforce the system.
“What happened yesterday cannot ever happen again,” he added. The European Council President Antonio Costa also said there was no indication that a cyber attack was behind the widespread power cut.
Five key seconds
The country’s grid operator, Red Electrica, on Tuesday shed some light on the series of still unaccounted-for events that caused the worst blackout in the country’s recent history. Although still lacking in detail, it begins to shed light on the cascading mishaps. “These are not definitive conclusions, we don’t have the complete information,” said Eduardo Prieto, director of services and operations at REE, said.
He set out the key five seconds for the Spanish electric grid. It was running smoothly until 12.33pm Madrid time on Monday, when something happened that was consistent with a loss of power generation in the south-west region of Spain. Then the system recovered as it should. Just 1.5 seconds after that, another event happened – likely a loss of generation. Then, 3.5 seconds later, there was a disruption in the connection between Spain and France, which isolated the peninsula from Europe’s power grid.
After that there was a big disconnection of renewable power generation. The system was then not able to survive with such an extreme disruption, Prieto said.
Error or bad luck?
Spain is one of Europe's biggest producers of renewable energy, but Monday's shutdown has already sparked debate about whether the volatility of supply from solar or wind has made its power systems more vulnerable to such a blackout.
Experts have told The National that nothing can be ruled out, although claims that the rush to achieve net zero with solar and wind energy are unlikely to have contributed to the crisis.
Spain did suggest that a “rare atmospheric phenomenon” might have been the cause which has led scientists to review whether a “solar maximum” flare could have resulted, as the 11-year cycle of the phenomenon is likely to reach its zenith in July.
Keith Bell, co-director of UK Energy Research Centre (UKERC), a future energy think tank, said that the cause could be down to “an unfortunate coincidence of things” that included human error, incorrect engineering or “just bad luck”.
“The authorities will be looking at whether there were any faults in the system, whether automatic protection and control equipment responded in the right way,” he told The National. “There's a whole range of different devices that will be examined to see if they responded correctly.”
John Kemp, an energy analyst and public policy specialist, said finding clear root causes for the sequence of failures that contributed to the blackout could take several months.
“The region has one of the world’s highest penetrations of renewable generation from wind and solar so the blackout will be a case study of how renewable generators impact on reliability as well as restarting after widespread failure,” he said.
Rare atmosphere
Portuguese grid operator REN denied on Tuesday it was behind a message circulated on social media attributing the blackout to a rare atmospheric event.
The message in Portuguese said there was a “fault” in the Spanish electricity grid linked to “abnormal oscillations were recorded in the very high-voltage lines (400 kV), a phenomenon known as 'induced atmospheric vibration'.”
The Spanish authorities did suggest that one cause might have been a “rare atmospheric phenomenon”.
The “solar max” flare occurs when particles get accelerated to very high energy by the Sun's radiation, which ionises them and creates plasma that charges through space. This can have an impact on the Earth, although there is usually some warning.
“That is a potential threat to power systems and in the past solar storms caused some major electricity network outages and damage,” Mr Bell said. “It is something that system operators need to pay attention to but there are a huge number of possibilities for what caused this.”
Mervyn Freeman, the British Antarctic Survey’s deputy leader of space weather, told The National that he had checked his readings on Monday that were likely to have discounted the theory.
“When it happened, I immediately looked at the space weather and my conclusion was that they were pretty average conditions so there didn't seem to be any obvious cause for a power outage from the space weather perspective.”
Not Net-zero rush
On reports that Spain was using 53 per cent of its energy needs from wind and solar on Monday and that a surge could have overwhelmed the system, Mr Bell discounted the theory stating that there would be the “same security margins” within the power network “regardless of the source of energy they were getting”.
He added that it was highly improbable that renewable energy had been rushed out without sufficient contingency planning.
The outage comes just weeks after the UK’s Heathrow Airport was forced to halt operations for almost a day after a power cut caused by a substation fire.
Britain’s home secretary said she was examining “different kinds of challenges and threats” to the energy grid after the Spain outage.
Asked whether the power cut there had triggered a fear that British infrastructure could be affected in the same way, Yvette Cooper told Sky News that the UK has a “continued approach” to “resilience and security issues”.
