alt Hacker NewsSpain does have few (probably 4 according to ESP Wikipedia) pumped-storage hydroelectricity plants. Supposedly these are being used nowadays to store excess of energy produced by fotovoltaic plants. No idea how fast these can switch from storing energy to producing it and if these were used to help during the blackout.
> No idea how fast these can switch from storing energy to producing it and if these were used to help during the blackout.
Typically ~10 seconds.
The bigger issue is if these have blackstart capability. (IE, if they can switch to generation when there is a blackout, or if they need power from the grid to start.)