Spain’s worst-ever blackout on 28 April was caused by a sudden collapse in power generation across three southern provinces.
This triggered a complete failure of the electricity system across mainland Spain and Portugal says a report into the blackout.
At 12:33 p.m., three near-simultaneous losses in Granada, Badajoz and Seville knocked out 2.2GW of generation in just 20 seconds.
The rapid drop in output caused critical frequency and voltage fluctuations that cascaded through the grid, overwhelming protection systems and cutting power to more than 50 million people.
Investigators have ruled out sabotage, cyberattacks or capacity shortages.
Spain was exporting power at the time, with solar and wind providing over 70% of its electricity.
Renewables part of the issue
The system’s heavy reliance on variable renewables – and a lack of stable synchronous generation like gas or nuclear in the affected areas, meant it was unable to absorb the shock.
The blackout severed interconnection with France, adding to the instability.
Early speculation about weather anomalies was dismissed by meteorological agencies, which reported no unusual conditions.
The failure has sparked debate about the resilience of Spain’s energy transition.
While solar and wind are now dominant, critics argue the system lacks the flexibility, backup and storage needed to manage shocks.
The affected areas were particularly vulnerable due to limited grid redundancy and weak support from neighbouring zones.
More protection
Power was restored in phases, with full service returning by 4 a.m. the next day. But the incident has reignited calls for a rebalancing of the grid mix, faster deployment of battery storage and improved coordination between regional operators.
The government insists its clean energy ambitions remain on track but a full technical report is expected to examine whether system design, planning or operational decisions contributed to the severity of the outage.
In the meantime, Spain’s grid operator is reviewing protocols to prevent a repeat of the April collapse.
Copyright © 2025 Energy Live News LtdELN