You should read the report, its a good description of a complex system failing complexly. (well the reasons leading up to it failing were complex)
The interesting thing about spain's grid is that it doesn't have that much battery compared to say the UK (the uk has about 11 gwhr which is about enough to power the entire uk for around 20mins)
The Iberian grid has <100Mw (I know mixed units) battery at the moment. This is interesting because the economics of the iberian grid means that most solar plants are in curtailment (ie told to turn off) at solar mid day prices are normally negative, at 18:00 prices are very high.
There is currently a large lucrative market in grid scale batteries being paid to charge at solar noon and getting a 30-50% premium to release the power at peak.
There are only a few companies that are able to vertically integrate solar and battery, so it'll be interesting to see how the prices shape up in the next 5 years. I expect a bunch of batteries to be built and then sold as the market changes shape.
Because you'd have to have engineered the whole thing for that purpose right from the get go. In theory you can run the generators in reverse and push water up the hill into the basin. In practice this may not work for a multitude of reasons (priming, encasement, rotation reversal, cavitation, impeller and impeller housing design).
The big thing with renewables is that they don't really require ongoing fuel shipments. Spain is not a large producer of any of the major fossil fuels like oil, gas and coal.
While there are certainly issues with the supply chain of certain components of renewables, those effectively cease after installation. And even hydro is not totally immune from supply issues given increasing drought frequencies across the world.
The proximal cause of the blackout was a single faulty solar inverter in a PV plant. The distal cause, however, was inappropriate disconnection of wind/solar generation and widespread cascading failure of reactive power support across the grid. Add to that a whole bunch of noncompliant transformers which tripped inappropriately, and Spanish grid operators inability to react appropriately.
It looks like you know way more than the entso report. Which mostly blamed it on governance. Mostly because a small change in a complex system can lead to cascading failures. They also included data to prevent it in the future. And yes solar and wind power makes these failures more complex but they are certainly not to blame. (Just read the article…)
I already said REE (the operator) was partly to blame, but they were reacting to something their grid was ill equipped to deal with.
Perhaps you should understand the difference between distal and proximal causes of events? Both are important. PV inverter–induced voltage oscillation was the proximal cause. Where did this come from? It's explained in the operators own report:
> During the incident analysis, it was determined that the oscillation was not natural to the system but rather
forced. This oscillation is observed with significant amplitude at a Photovoltaic Plant located in province of
Badajoz (PV Plant A). At the time of the oscillations, the plant was generating approximately 250 MW. Since
the oscillation was forced, it ceased once the plant stabilizes it.
The rate of new solar capacity is falling though, according to that graph.
And:
"With annual additions now around 1 GW, UNEF is calling for stronger momentum to maintain progress towards 2030 targets"
"Growth, however, has slowed, with only around one gigawatt added last year. To reach the national target of 19 gigawatts by 2030, deployment will need to accelerate, the association" [0]
The 2026 Ember report said that 99% of new global electricity demand was met by solar. Solar broke its previous records on relative and absolute installed numbers. Fossil fuel usage shrank. There might be regional changes, but there is no stopping solar.
The interesting thing about spain's grid is that it doesn't have that much battery compared to say the UK (the uk has about 11 gwhr which is about enough to power the entire uk for around 20mins)
The Iberian grid has <100Mw (I know mixed units) battery at the moment. This is interesting because the economics of the iberian grid means that most solar plants are in curtailment (ie told to turn off) at solar mid day prices are normally negative, at 18:00 prices are very high.
There is currently a large lucrative market in grid scale batteries being paid to charge at solar noon and getting a 30-50% premium to release the power at peak.
There are only a few companies that are able to vertically integrate solar and battery, so it'll be interesting to see how the prices shape up in the next 5 years. I expect a bunch of batteries to be built and then sold as the market changes shape.
While there are certainly issues with the supply chain of certain components of renewables, those effectively cease after installation. And even hydro is not totally immune from supply issues given increasing drought frequencies across the world.
/s
Perhaps you should understand the difference between distal and proximal causes of events? Both are important. PV inverter–induced voltage oscillation was the proximal cause. Where did this come from? It's explained in the operators own report:
> During the incident analysis, it was determined that the oscillation was not natural to the system but rather forced. This oscillation is observed with significant amplitude at a Photovoltaic Plant located in province of Badajoz (PV Plant A). At the time of the oscillations, the plant was generating approximately 250 MW. Since the oscillation was forced, it ceased once the plant stabilizes it.
https://www.youtube.com/watch?v=8CwB38oLEYM
Solar Saturation & Grid Collapse: Spain's BESS Opportunity - Modo Energy
As these renewables and grid change to a different configuration/inverter technology, this problem shouldn't happen again?
[0] https://www.entsoe.eu/publications/blackout/28-april-2025-ib...
So, what caused the blackput?
The root cause tree with its multiple roots on page 23 is a good start.
And:
"With annual additions now around 1 GW, UNEF is calling for stronger momentum to maintain progress towards 2030 targets"
"Growth, however, has slowed, with only around one gigawatt added last year. To reach the national target of 19 gigawatts by 2030, deployment will need to accelerate, the association" [0]
[0] https://www.pveurope.eu/markets/spains-solar-market-hits-93-...
https://ember-energy.org/latest-insights/global-electricity-...