What caused the blackout in Spain and Portugal and did renewable energy play a part?

Spain and Portugal suffered the worst blackout in living memory in Europe this week. About 55 million people were affected and it lasted more than half a day. Some have blamed renewables and net zero emissions targets, as the two countries boast high levels of wind and solar on their electricity grid and lead Europe in the technologies. But is this true?

What happened?

Some initial reports suggested a “rare atmospheric phenomenon” may have been to blame, citing a statement attributed to the Portuguese grid operator REN. In extreme weather, such as storms and heatwaves, the cables that carry electricity overhead can oscillate, which can cause problems with the conductors, particularly on older and less well maintained equipment. However, the weather in Spain was normal on Monday. On Tuesday REN denied it had been responsible for the statement, but did not give further details.