Iberian Blackout Raises Concerns Over Renewables-Heavy Power Grids

The incident is ‘a lesson in trigger events and systemic risk, both of which are exaggerated by renewables,’ analyst Andy Mayer says.

Customers dine in a restaurant illuminated by a generator during a blackout in Barcelona, Spain, dated April 28, 2025. Emilio Morenatti/AP Photo

For one day in the sunny Iberian Peninsula, the lights went off. It has been described as the worst blackout in living memory in Europe.

With power now restored, authorities are probing the root cause, but energy analysts say the region’s heavy reliance on intermittent renewables may have enabled the grid collapse.