The technical services of the CNMC have expanded the number of sanctioning files related to the massive blackout suffered in the Iberian Peninsula on April 28, 2025. After the twenty procedures initiated just a week ago, the Commission announced this Friday “the opening of”. Specifically, 35, mostly to Iberdrola, which has added 18, and to Endesa, with 12 new ones. The CNMC has also activated one, respectively, for Engie, TotalEnergies and Contour Global, one of the main operators of solar thermal plants owned by the KKR fund. At the same time, it has announced the filing of separate files against the Ascó nuclear power plant, of a serious nature, and another very serious one against the Alamaraz plant.
Specifically, the CNMC attributes to the company Centrales Nucleares Almaraz-Trillo, the company through which Iberdrola, Endesa and Naturgy share ownership of the plant, a possible violation of article 64.37 of the Electricity Sector Law, due to a reduction in production or supply without authorization/Repeated non-compliance with availability obligations.
The openings notified this Friday also include “the investigation of practices that occurred on days or periods other than April 28, 2025, but which would also constitute indications of possible sectoral infractions detected within the framework of the investigation,” explains the regulatory body. In all the files (except for the Ascó-Vandellós Association, which is for alleged price manipulation), like those opened last week, it would be a serious violation of article 65.8 of the Electricity Sector Law (LSE) for allegedly failing to comply with article 64.15, 16 and 17 (voltage controls) “without risk of guarantee of supply or serious damage.” That of Red Eléctrica was the only case of very serious infringement, for having allegedly failed to comply with one of its operating functions “with detriment to the system or subjects.”
On April 17, the CNMC agreed to file: one against Red Eléctrica, for alleged non-compliance with one of its functions as system operator, which implies a very serious infraction against the Electricity Sector Law; another 17 files on as many hydraulic and gas facilities and two nuclear plants of the three large electricity plants (Endesa, Iberdrola and Naturgy); one to Repsol’s electricity generation subsidiary and another to the combined cycle of Bahía de Bizcaia Electricidad. In this case, serious violations due to breaches of the law “without risk to the security of supply”, which, in principle, would not be the cause of the blackout. Furthermore, the case would not be resolved for a year and a half, the period for the investigation of said files.
Endesa’s files published last week included its two Catalan nuclear power plants (Ascó and Vandellós), which appear again on the new list, as well as a string of almost unknown small hydroelectric plants: those of Biesca, Ondinas, Mequinenza, Mediano and Ribarroja. The case of these Endesa nuclear plants is clear evidence that these investigations are unrelated to the blackout, since they refer, according to the CNMC, “to offers with abnormal or disproportionate values to unduly alter the dispatch of the generation units or the matching of the market”, in other words, to alleged price manipulation.
According to the company’s CEO, José Bogas, last Monday in , the investigations date back to events two years before the blackout, except for two cases, that of Ondinas and Biescas (12 hours before), which, in his words, were not legally obliged to control voltage, given their low production. The CEO of Endesa said that several of them, due to their production volume, were not obliged to comply with voltage controls and, in any case, did not contribute to the blackout.
As he insisted, the openings of files refer to investigations from two years earlier and, he already warned in his intervention, that he anticipated that the CNMC would open “more files”, as happened yesterday. It is unknown if it will continue to dust off files but, in any case, if it opens new ones, after April 28, those potentially affected by damages who intend to claim will no longer be able to do so against new files, since the deadline for doing so expires on that day. It also doesn’t help them much if, as in those published this Friday, they are not related to the blackout.
CNMC errors
among them, those of Palos and Sagunto, and two hydroelectric plants, while those of Iberdrola have fallen, among others, on Almaraz and its hydraulic plant in Aldeadávila. According to business sources, due to an error by the CNMC, ownership has been attributed to its generation subsidiary, when it belongs to the group (community of assets) that includes Almaraz and Trillo, in which Iberdrola has 52%.
The supervisor has also made the error of attributing to the parent company, Iberdrola SA, the ownership of a facility of its generation subsidiary, as it appeared in the files published on the 17th.
