The sweeping power outage that hit Spain and Portugal this week has raised questions about the electricity grid in a region not normally known for blackouts

An unprecedented blackout brought much of Spain and Portugal to a standstill Monday, stranding thousands of train passengers and

Spain's national grid operator Red Eléctrica de España has ruled out a cyberattack and pointed to a drop in solar generation as the preliminary cause of the country's power outage, El Pais reports.