The third regulatory period for electricity distribution under the TOTEX model in the United Kingdom is expected to begin in two years.

Spain's power grid has a regulatory exception allowing it to operate at up to 435 volts, whereas the standard European upper voltage limit is 420 volts.

On the day of the blackout, the basic voltage control systems used by renewable energy plants in Spain, which were compliant with regulations at the time, actually worsened grid instability.

The Iberian Peninsula blackout did not have a single trigger event, but was instead caused by a chain reaction from automatic protection systems.

On the day of the blackout, Spanish TSO Red Electrica manually switched 84 shunt reactors on and off between 9:00 AM and 12:30 PM, an average rate of one operation every 2.5 minutes.

After a five-year approval process, Spain has changed its regulations to allow renewable energy sources to participate in providing voltage control services to the grid.

During the Iberian Peninsula blackout, some dispatchable power plants that were expected to provide voltage support either failed to do so or exacerbated the problem.

At the time of the blackout, Spain's regulations limited the provision of voltage support services to dispatchable power plants.

Under Spain's new rules, renewable energy plants that provide voltage control services will receive payment and be given priority dispatch, reducing the likelihood of curtailment.

Traditional regulatory models for European power grids are often based on capital expenditure (CAPEX), rewarding utilities for building new assets rather than optimizing operational practices.

The United Kingdom pioneered a total expenditure (TOTEX) regulatory model for its power grid, which is now being adopted by many other countries.

Operating grid equipment in Spain at higher voltages than the standard 420-volt testing level reduces its lifespan and makes failures more unpredictable.

The transmission system operator (TSO), regulator, and power generators in Spain had inconsistent understandings of the applicable voltage rules, which hindered coordination during the emergency.

The United Kingdom is currently in its third regulatory period for electricity transmission under the TOTEX model.

Spain began participating in the European 15-minute power dispatch market approximately one month before the major blackout occurred.

The ENSO-E report on the Spanish blackout recommended that all European Transmission System Operators (TSOs) increase automation of grid control systems.