Spain: Energy companies blame grid operator for blackout

The Spanish energy companies association (Aelec), which includes EDP, Endesa and Iberdrola, attributed the April blackout to the Spanish electricity grid operator's poor management in controlling voltage fluctuations and overloads.

“The main cause of the zero electricity was a serious failure in the voltage control of the electrical system” due to “poor programming”, said the association’s leader Marta Castro, at a press conference in Madrid. The association says that not enough production facilities were activated by the company Red Elétrica (REE), the Spanish system operator, despite there being sufficient installed capacity and resources.

Aelec today presented the conclusions of a study by “independent technical experts”, entitled “Analysis of the events that led to the electricity zero of April 28, 2025”, which affected the entire Iberian Peninsula.

The study was carried out by the consultancy firm Compass Lexecon in conjunction with INESC TEC – Institute of Systems Engineering and Computer Technology, of the Faculty of Engineering of the University of Porto. Marta Castro said, at the end of the presentation of the study by two of the authors (both from Compass Lexecon), that Aelec “fully agrees with the diagnosis of the independent experts” and attributed responsibility for the collapse to REE.

REE is “solely responsible” for guaranteeing the security of electricity supply in Spain and “also for controlling voltage levels in the grid”, she stressed. “The problem on the 28th was due to the fact that Red Eléctrica did not activate all the available resources within its reach to avoid voltage fluctuations in the transmission grid, which were recorded not only moments before, but also in the days and hours preceding the blackout”, stated Marta Castro.

The Aelec director denied, on the other hand, that the power plants of the organization's member companies were disconnected on April 28 in an "improper" manner or that there was a failure to comply with obligations on the part of the electricity companies, as alleged by REE last week. The same is suggested by the report of the commission created by the Spanish Government.

Marta Castro also guaranteed that all photovoltaic installations of Aelec companies in the Badajoz area operated normally during and before the blackout and continue to operate, with authorization and at the request of REE.

The commission created by the Government and REE's internal report on the blackout identified a large and anomalous oscillation in a photovoltaic unit in the Badajoz area on the day of the blackout, which the Spanish press says was from Iberdrola.

Aelec's member companies represent 45% of the installed generation capacity in Spain and 78% of the distribution networks.