Spain's competition regulator adds renewables sector to sanctioning proceedings for 2025 blackout

Spain’s competition watchdog, the CNMC, has expanded its investigation into the nationwide blackout of 28 April 2025. While initial proceedings targeted the system operator, Red Eléctrica, followed by nuclear and gas providers, the regulator has now turned its attention to the renewable energy sector.

The CNMC recently announced sanctioning proceedings against Mercuria Solar for a "serious infraction" relating to voltage fluctuations in the months leading up to the blackout. Under current regulations, such infractions can carry fines of up to €6 million. This brings the total number of investigations opened by the regulator since 17 April to 66.

Renewable energy facilities have been under scrutiny since the immediate aftermath of the power outage. Red Eléctrica has argued that the rapid integration of these plants into the national grid - and their subsequent shutdowns - increases voltage instability.

The main official reports on the blackout published in recent months have stated that the failure had a multifactorial and unknown origin and have ruled out renewable energy sources as the cause of the blackout.

The investigations, however, did point out weaknesses in voltage control, which led the CNMC to approve, just one month after the incident, operating procedure 7.4, key to voltage control.

This is no trivial matter. Most of the cases so far involve energy giants Endesa, Iberdrola, Naturgy and Red Eléctrica. Just this week, President of Red Eléctrica Beatriz Corredor filed objections and denounced a "conflict of interest" on the part of the regulator in an unprecedented war between the two companies.

Red Eléctrica has criticised in various forums the legal vacuum that the CNMC has allegedly maintained by failing to update operating procedure (OP) 7.4 in a timely manner. This procedure, in force since 2000, is key to voltage control.

Head of the CNMC Cani Fernández has flatly rejected this accusation, denying that the body had shelved the update to the regulation and assuring that there were "sufficient" mechanisms for controlling the voltage that caused the electrical collapse.