After Spain’s Vice-President and Minister for Ecological Transition and Demographic Challenges, Sara Aagesen, identified excessive voltage in the transmission grid and planning errors by transmission grid operator Red Eléctrica de España (REE) as the causes of the blackout on the Iberian Peninsula on 28 April 2025, REE is now providing a more detailed account of the circumstances in its own statement.
According to this, an atypical oscillation of 0.6 hertz occurred at a large solar power plant in the province of Badajoz, which led to voltage fluctuations in the grid. At that time, the plant was feeding in around 250 MW of power. The report states that the oscillation was probably due to an internal malfunction of the solar plant. The incident triggered a series of emergency measures that altered the flow of electricity and affected the stability of the system. When the frequency dropped below 49.5 hertz, large consumers shut down and a conventional power plant was taken off the grid unscheduled. When the frequency fell below 48 hertz, Spanish nuclear power plants shut down and the direct current line to France was cut. At this point, the widespread blackout was unstoppable.
© PHOTON
