We have second to second the data on the great blackout in Spain. They complicate everything even more

The great blackout of April 28 left us all with more questions than answers. Now, with the “black box” of the electrical system in the hands of the researchers, the preliminary data, far from offering a simple explanation, have added a level of complexity to an unprecedented energy crisis.

To begin with, what seemed like an abrupt power fall was rather a sequence of three impacts. We knew of two disconnectionsbut as confirmed by Vice President Third Sara Aagesen, there was a third incident exactly 19 seconds Before the blackout, at 12:33.

This first shake, located south of the Peninsula, adds to the two already known in the southwest, which triggered the cascade of the network. Although the system was able to absorb this first alteration, its existence adds a new layer of intrigues to an intricate technical autopsy.

Researchers face the forensic analysis of about 70,000 critical points that show data every 20 milliseconds. Unraveling the exact sequence in those five fateful seconds between 12:33:16 and 12:33:21, and now also in the previous 19 seconds, is what light will shed on the questions that Red Electrica still does not answer.

What was the first domino card to fall? How did the rest of the system react? Were the backs failed? The volume and granularity of information They predict months of workas happened after the Texas blackout in 2021 or that of Italy in 2003, where the final responses took months to arrive.

Fortunately, there is a deadline, imposed by the European Commission: Spain has three months to deliver its conclusions about the blackout and A resilience plan that, predictably, will have implications at the paneuropeo level.

Collapse anatomy

• 12:32:57 on Monday, April 28. First blow. The frequency of the peninsular network experienced a slight fall, a few hundredths below 50 Hz. The system absorbed the oscillation in milliseconds, as in normal circumstances. But it was a first warning: a first loss of generation in the south of the registered peninsula 19 seconds before energy zero. The Investigation Committee has already baptized it as the “third event”, although chronologically it was the first. Has been discovered after scrutinizing in detail the log of Eléctrica Red, which monitors those 70,000 critical points by turning data every 20 milliseconds.
• 12:33:16. Second blow. A new and powerful oscillation in the southwest dynamite the available operational reserve. The frequency sinks this time below critics 49.85 Hz. Given this fall, converters of an important part of the photovoltaic generation begin to disconnect automatically to protect the equipment.
• 12: 33: 17-12: 33: 21. KO Technical. In just four seconds, the frequency fall is accelerated unrecoverable. The interconnection with France jumps, and then that of Morocco. The network loses 15 GW of power, the equivalent of 60% of the peninsular generation at that time. Then go black. Spain and Portugal sign their first energy zero.
• 03:30 on Tuesday, April 29. To restore service from black, network operators carry out a Black-Start unprecedented, first starting the pumping hydraulics, followed by combined gas cycles. Red Eléctrica announced that 99.95% of the supply It had been restored 15 hours after the blackout. No one in Europe had risen from scratch a network of this size with such a high proportion of renewable energy.

Renewables in the epicenter of debate

While technical research progresses with stealth, the public debate is a Theories Polvorín Waiting for answers. The hypothesis of a cyber attack He has flown the crisis from the first moment, despite the fact that Eduardo Prieto, director of Operations of Electric, will discard it sharply.

Beyond that, the growing weight of renewables in the energy mix (More than 50% of production in 2024) has placed solar and wind energies in the eye of the hurricane. Its intermittent nature and its lack of synchronous inertia (the ability of conventional plants to stabilize the network thanks to its great rotating masses) They make the most vulnerable system to frequency imbalances.

The electricity grid must maintain a constant balance between generation and consumption, operating at a frequency of 50 Hz. An important mismatch can compromise the entire infrastructure. Renewable sources, depending on the sun or wind, and connecting through power electronics (famous investors), do not have that mechanical inertia.

Since there are solutions such as energy storage (batteries or pumping centrals) and “Grid Formers” (investors designed to stabilize the network), the question is whether the system is sufficiently adapted to renewables.

A May 2024 Report Published by the Electric Red itself, not suspect. Entitled ‘General Criteria for the Protection of the Spanish Electrical System’, warned of the need for Adapt protection criteria before “the change in the generation mix of the current electrical system due to the massive entry of renewable energy sources.”

The text recognized that, in areas with high generation penetration based on power electronics, “situations could occur in which the behavior of some of the current protection functions was not expected”, being able to lead to the “disconnection of large amounts of renewable generation”, causing possible serious imbalances.

American analyst Russ Schussler It has been warning for years that replacing synchronous generators with investor -based resources (wind, solar) increases the risk of blackouts, and that the lack of inertia is a key factor. Jordi Sevillaformer president of Electrica, believes that the National Integrated Plan for Energy and Climate Peque of “Too Renewable Messianism” without sufficiently attending to these technical problems and the lack of investment.

Images | Endesa, Fernando Rodríguez (RTE data)

In Xataka | The total blackout of Spain has a suspicious number 1: a stabilization of the poor electricity grid