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).

Spain 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.

Reconfiguring dams for storage isn't easy, quick or possible.

Non-storage dams don't have lower lakes to pull from, and the surrounding area might not be able to support it.

plus they also need water when there are droughts, which spain is also prone to.

they do it all the time

Yes obviously

what is the point of this comment?

But you need less than if you were to go fully fueled. One hedges the other.

It is a complex system. There is no single cause. There's a multitude of causes.

The root cause tree with its multiple roots on page 23 is a good start.

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. 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 reason is that classical grids are mostly self-correcting. Rotating inertia can stabilize frequency and can produce or absorb reactive power.

"Reactive power" sounds fancy, but it just means that motors can create a drag. The power lines are giant capacitors, and capacitors have the lowest effective resistance when they are discharged. So the current is greatest when the voltage crosses the zero mark. Inductive (rotating) loads are the opposite, their effective resistance is greatest when the current starts to rise or fall. So this limits the initial inrush of the current.

But there's more! When you have a transformer and a long line, you can essentially get a boost converter. The voltage from a transformer travels through a low-resistance wire until it reaches the end, and because the line can be modeled as a series of capacitors, you essentially get a "charge pump" ( https://en.wikipedia.org/wiki/Charge_pump ). From the viewpoint of the generator you have one large capacitor, but from the viewpoint of a consumer in the middle of the line, you have two capacitors in series.

As a result, the voltage in power lines can _spike_ if there's not enough rotating load. This is called Ferranti effect, and in Spain it was the primary reason for the faults.

This is all fixable, but it requires investment and regulation. And Spain (and other countries) have been neglecting that, by incentivizing the cheapest possible generation.

Their script is over active. Not sure why people are harvesting HN likes.

So you can select all images with traffic lights.

True, but it conveniently hides the fact that voltage control becomes more of a problem in a low inductance environment.

Good news. But "there is no stopping solar" is a straw-man. Nobody said it's stopping.

(Also, I'm discussing an apparent slowdown in Spain's rate of new solar capacity (given the article is about Spain). And global trends are not too relevant to that topic. We all know it's easy to hide issues in global stats – domestic consumers Spain won't care if China increases their solar by 1000000%, for example.)

Yup, hopefully the Spanish Government will address the slow down and announce a commitment to keep up the pace (if not already). Though of course they are already doing very, very well.