Summary of Spain and Portugal Power Outage 4/29

On April 28, 2025, a massive power outage affected millions of people in Spain and Portugal, leaving them without electricity for nearly 18 hours. The blackout was the largest in Europe's history, with trains, traffic lights, ATMs, phone connections, and internet access failing across the Iberian Peninsula.

What Happened

The power outage occurred at around 12:30 pm local time, when a sudden drop in generating capacity of 15 gigawatts (GW) was recorded on the Spanish grid. This caused a frequency event that triggered automatic load shedding defense plans, disconnecting consumers and causing the Iberian electricity system to collapse.

Cause of the Outage

The cause of the outage remains unclear, with officials ruling out human error, meteorological causes, and cybersecurity attacks. The initial trigger is still uncertain, but experts believe it may have been related to a series of generation trips on the Spanish grid.

Impact on Renewable Energy

Some media outlets and politicians quickly pointed to renewable energy as a possible cause of the blackout, citing Spain's high reliance on solar power. However, experts noted that while solar power was likely involved in the initial frequency event, it is not clear if it was the ultimate cause of the blackout.

Investigations and Responses

Both Spanish and Portuguese authorities have launched investigations into the cause of the outage. The European Union has also announced a thorough investigation. In response to the blackout, some politicians and commentators called for increased focus on grid stability and resilience, while others argued that the incident should not be used as an excuse to slow down the transition to renewable energy.

Power Restoration

By Tuesday morning, electricity had been restored to most areas of both countries, leaving many relieved but also sharply critical about what exactly had caused the power failure.