Power surge caused April’s massive blackout in Spain and Portugal

Following the massive power outage in Spain and Portugal in April, an investigation report released on Tuesday revealed that the blackout was caused by a power surge.

The power surge on April 28 triggered a chain reaction of protective shutdowns, Spanish Deputy Prime Minister and Environment Minister Sara Aagesen said in Madrid.

Aagesen emphasized that there were no indications of a cyberattack.

The power outage largely paralysed the country for more than 10 hours. Many industrial companies, such as Volkswagen in Pamplona and its subsidiary Seat near Barcelona, had to interrupt production.

The power surge in the Spanish electricity grid was triggered by several factors, she said. On the one hand, the grid operator Red Eléctrica did not plan electricity production with the “necessary caution.”

This means that not enough power generation plants were planned that, like traditional power plants with turbines, can better cushion power surges in the grid than most solar or wind power plants, she said.

On the other hand, the operators of conventional power plants, such as combined power plants, nuclear power plants and hydroelectric power plants, also behaved “inappropriately,” said Aagesen.

They did not absorb enough excessive voltage from the grid, resulting in other power plants being disconnected from the grid, she said.

However, it remained unclear why Red Eléctrica planned so carelessly and why power plant operators behaved incorrectly. Aagesen merely hinted at a lack of coordination, unclear responsibilities and a lack of transparency in the overall system.

According to experts such as those from Germany’s Federal Network Agency, additional investment is needed to keep an electricity grid with an ever-increasing share of solar and wind power plants stable.