Overview

• The blackout struck at 12:33 local time on 28 April, cutting power and communications across Spain and Portugal.
• The ENTSO-E panel describes Europe’s most serious outage in two decades and the first linked to cascading overvoltages.
• A surge set off production losses and chain disconnections at thermal and renewable plants following two pre-event swings in power, voltage and frequency.
• Operators reduced Spanish exports to France to curb fluctuations, a step the report says heightened voltage on the Iberian system.
• Some stakeholders withheld data needed for the inquiry, so a final root-cause analysis with recommendations is scheduled for the first quarter of 2026.