Rayner Pena/EPA
The problem occurred in April, but voltage fluctuations had already been commented on – and alerted – in January.
The biggest ever in the Iberian Peninsula occurred on April 28, 2025. Practically a year later, it is still a topic.
The end of the panel of experts from the European Network of Electricity Transmission System Managers (ENTSOE) had already made it clear that the origin of the problem – or combination of several problems – was in Spain.
Overall, ENTSOE emphasizes that Spain should have better voltage control capabilities, regardless of production technology. In addition to indicating that it was difficult to collect local information.
Now, talks between the Spanish Electric Network (REE) and several energy distribution companies are being disclosed. And these recordings show that the Spanish officials were already “guessing” the blackout.
The blackout was in April but, in January, came the warning in Barcelona: “Something that was under control at a normal load level, with normal voltage, is suddenly pushed to the limit and voltage drops.” And yet: “Today was extremely bad” – while meetings were suggested to try to resolve the issues.
The technician at the distribution control center in Barcelona comments: “In Ascó, they were about to have one of the generators shut down and, of course, with this export, if the generators shut down, we will run out of energy.” REE admits: “It’s been a really sharp fluctuation. So, I don’t know, they will have to… analyze everything with the companies and see what happens.”
Already in April, exactly three weeks before the Iberian blackout, in Seville: “We have a huge problem with voltage, a serious problem, everything is extremely low. They need to help us”.
The photovoltaic energy oscillation was “eternal” and happened in “all of Spain” that April 7th.
The REE operator comments, still on April 7th: “No, we can’t handle that, because… at some point It is almost certain that we will collapse.”
