Damián Cortinas: Spain Blackout Caused by Voltage Control Issues, Not Renewable Energy
The final report of the Expert Panel on the 28 April 2025 blackout in continental Spain and Portugal identifies its causes and outlines recommendations to strengthen the resilience of Europe’s interconnected electricity system. It was prepared by a 49-member Panel including representatives from Transmission System Operators (TSOs), Regional Coordination Centres (RCCs), ACER and National Regulatory Authorities (NRAs), and was chaired by experts from two unaffected TSOs.
The investigation concludes that the blackout resulted from a combination of many interacting factors, including oscillations, gaps in voltage and reactive power control, differences in voltage regulation practices, rapid output reductions and generator disconnections in Spain, and uneven stabilisation capabilities. These factors led to fast increases of voltage and cascading generation disconnections in Spain, resulting in the blackout in continental Spain and Portugal.
At a press briefing, Damián Cortinas, Chair of the ENTSO-E Board of Directors, clarified: “The problem is not renewable energy, but voltage control, regardless of the type of generation”. He added: “This isn’t about high technology; it’s something we’ve been able to do for decades.” Experts have made recommendations to prevent similar situations in Europe, such as strengthening operational practices, improving monitoring of system behaviour, closer coordination and data sharing among electricity system operators. Furthermore, they have highlighted the need to adapt regulatory frameworks to implement these recommendations in line with the changing nature of the electricity system.
The 28 April 2025 blackout was a first of its kind event, and the recommendations aim to strengthen system resilience with solutions that are already technologically deployable. This blackout highlights how developments at the local level can have system-wide implications and underlines the importance of maintaining strong links between local and European system behaviour and coordination, while ensuring that market mechanisms, regulatory frameworks and energy policies remain aligned with the physical limits of the system.
Read the full report here.
