Data requirements, models, and simulation of an overvoltage-driven blackout: an academic perspective

Abstract

At 12:33 on 28th April 2025, a blackout occurred in the Iberian electricity system. Sixty million people lost the electricity supply. This is the first time in the history of the Spanish peninsular electricity system that a blackout has occurred. It is only comparable in continental Europe in terms of severity to the blackout of the Italian system on September 28, 2003. Although several factors and circumstances led to the blackout of the Iberian electricity system, according to the European Network of Transmission System Operators for Electricity (ENTSO-e), the most probable trigger was a cascading series of generation disconnections and voltage increases. In other words, it probably was an overvoltage-driven blackout. This contribution will discuss, from an academic perspective, the data requirements, models, and simulation results for such a blackout. The proposed simulation method and the obtained results will not only characterize the observed phenomena during the blackout of the Iberian electricity system, but will also provide indicators of system security. Moreover, such indicators will be used to assess actions adopted before and after the blackout. The contribution will also highlight indicators of voltage variability that led to initial generator disconnections.