“There are huge amounts of data that we now have to analyse to understand what happened,” Sánchez told reporters.
Whatever the findings, the crisis is sure to offer lessons for the way grids are operated as countries around the world shift to increasingly “electrified” energy systems that will place more burden on infrastructure and rely more heavily on renewable energy sources.
Seconds from chaos
According to Red Eléctrica, at 12.33pm on Monday, the country’s grid was hit by an event similar in nature to a sudden loss of power generation, seemingly in the south-west of the country.
Such disruptions can be serious because supply and demand must be balanced at all times for electricity grids to function, with the system’s frequency used to measure this.
Following the first event, which would have caused the frequency to drop, the Spanish grid’s computer systems reacted instantly to stabilise the network.
But after just 1.5 seconds, another loss of generation occurred. This was followed, 3.5 seconds later, by the failure of the electricity interconnectors linking Spain and France.
That left Iberia isolated from the rest of Europe, preventing grid operators from importing power to restore balance – and triggered a domino effect whereby solar and wind farms automatically disconnected from the grid en masse to protect themselves.
What followed was a cascading effect across the whole of Spain and Portugal as grid systems and generators shut down to prevent any damage.
At the lowest point, the power being generated fell to zero megawatts – a total blackout, and the first of its kind in Spanish history.
But what was the initial problem that led to these cascading faults?
At Tuesday’s press conference, Eduardo Prieto, director of operational services for Red Eléctrica, told reporters it was “very possible” that the fault had originated from a solar farm in the country’s south-west.
Data published by the company show that about 70pc of Spain’s solar generation is concentrated in the southern provinces of Andalucia (24.3pc), Extremadura (24.3pc) and Castilla La Mancha (22.2pc).
