Red Eléctrica has produced and released a documentary to mark the first anniversary of the blackout that on April 28, 2025, left a large part of Spanish territory without electricity supply. The audiovisual piece focuses on the agility with which the company's teams managed to restore service and on the support for the subsequent investigation, as well as on the "transparency" in explaining what happened.
The documentary, titled 'April 28, One Year Later', reconstructs in the first person the development of the day of the electric zero, which the company describes as an "unprecedented, unpredictable, and multifactorial episode".
According to Red Eléctrica, April 28, 2025 began as an ordinary day, "with a correct technical restriction programming in accordance with current regulations"; however, it indicates that at 12:33 PM the system went to zero.
At that moment, the system operator (OS) immediately activated the restoration protocols with the priority objective of recovering the supply as soon as possible. The company states that "in a race against time, Red Eléctrica's teams executed thousands of technical decisions to recompose a puzzle of enormous complexity: more than 7,000 telematic maneuvers until supply was restored".
"Behind each one there were trained professionals, millimeter coordination, and a composure worked on for years. The result was a replacement that, despite its difficulty, was completed in record time," adds the company.
The protagonists involved in the film detail "how the replacement was managed and how, afterwards, the investigation was supported with rigorous analysis, delivery of information and institutional collaboration to clarify the facts", underlining that "the work did not end when the lights came back on".
Red Eléctrica defends that it has been proven that "it did not fail"
The company states that, as the months have passed, "the truth has been consolidating through official reports that unequivocally show that Red Eléctrica did not fail and there is no action or breach attributable to the system operator that led to the blackout on April 28th".
In this regard, it recalls that the panel of European experts attributes the origin of the incident to multiple factors and mentions two critical oscillations for the grid: a first, of a forced nature, located in a plant in Badajoz, and a second, inter-area, which possibly was triggered from the previous one.
Likewise, the panel identifies as the root cause the disconnection of a large volume of small domestic self-consumption photovoltaic installations during those oscillatory phenomena, which contributed to increasing grid voltages.
To this were added at least 9 incorrect generation disconnections, despite the fact that the voltage in the transmission network remained within the set margins. Furthermore, the Expert Panel concludes that several conventional generation units did not reach the minimum required by the voltage control regulations.
Red Eléctrica also indicates that the report incorporates simulations carried out by members of the Expert Panel external to the company, which show that, if those units had absorbed more reactive power, the electrical zero would not have occurred.
The panel of experts, the company continues, also recognizes that a greater contribution from renewable energies to the dynamic control of voltage would have been desirable, something that on the day of the blackout was not viable because the necessary regulations had not yet been approved. "Even so, Red Eléctrica operated the system correctly and reacted to all the incidents that arose that day, making adequate use of the available tools," it maintains.
In the documentary, it is recalled that the first clues about the origin of the event were detected from the beginning by Red Eléctrica and that "they were also circulating as hypotheses within the sector itself from the first hours".
The president of Redeia, Beatriz Corredor, recalls a high-level meeting held once the replenishment was completed, in which an executive from a large electricity company pointed to a plant of its property "which was already being spoken of as the origin of the blackout" and how, subsequently, the investigation granted that facility a particularly relevant role in the sequence of events.
From there, the company insists that "if there were intuitions from the first moment, it is especially difficult to accept that this reality continues to be questioned today, because it questions technical evidence and goes against the general interest".
A story based on transparency
On this first anniversary of the electric zero, Red Eléctrica aims with this documentary to highlight "the transparency and coherence of a narrative sustained from day one on a technical basis".
At the same time, it seeks to vindicate "a way of working that is only understood when heard in the first person: with regulations as a guide and a vocation of service that does not need grand words because it is demonstrated day by day".
In the company's opinion, that April 28th made it clear that "Red Eléctrica's professionals were, are, and will be at the service of the country".