Re: Grand Apagon - Electricity (not) in Spain

On 5/05/2025 1:23 am, Jeroen Belleman wrote:

On 5/4/25 10:49, Martin Brown wrote:

On 04/05/2025 01:27, Carlos E.R. wrote:

On 2025-05-04 01:53, john larkin wrote:

On Sat, 3 May 2025 23:55:17 +0200, "Carlos E.R."
<robin_listas@es.invalid> wrote:
>

On 2025-05-03 17:12, john larkin wrote:

On Sat, 3 May 2025 14:24:07 +0200, "Carlos E.R."
<robin_listas@es.invalid> wrote:
>

On 2025-05-02 12:03, Martin Brown wrote:

>

Spain doesn't have a great deal of battery storage or pumped water.

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Network grade batteries, none, I believe. There are plans for water
pump/generators. Some of the islands do have them.
>
It seems that solar panels and wind farms mostly have the type of
inverter that follow the shape of the voltage already in the grid, with
detection to bail out if things go nuts. There is the suspicion that
this was at least part of the problem.
>
But there is another type of inverters that force the shape, ie,
simulate inertia.

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Where do they get the energy from?

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Where does a gas turbine get the energy from?

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Wait, wait, let me think....
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Inertia, and then burning gas?
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Well, same thing.
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Batteries, and panels and wind flaps.

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But you do have to have serious stored energy available at the drop of a hat if the inverter is to effectively resist frequency being pulled down by the load.

 Not really. It should have a few percent of margin to increase
power delivered when the frequency drops. The point is that the
mains grid is composed of many generators. This only works if they
take collective action. The European grid collectively has a target
dP/dF in the 20GW/Hz ballpark. Any single installation will provide
only a tiny, tiny contribution.
 Solar PV is sufficiently important in Spain that it should contribute
its part. (It's in the 19GW ballpark, more than half of demand during
daytime.) I don't know if it does.
 

>
I suspect from the time of day when this happened it was over supply of solar PV leading to too high a frequency and/or over voltage events that led to the cascade failure. Unclear why it didn't pass through a stable state where supply matched demand though if that really was the case.

 Supply = demand is not a sufficient condition for dynamic stability,
anyway.
 

I suspect poor network stability analysis played a large part and the network was still relying on the intrinsic stability of the old turbine generators that were no longer present. Have to wait for the report.

 Yes. The problem has been anticipated for years.

The problem may have been expected for years, but "anticipating a problem" involves doing stuff to make it less of a problem when it does show up. There doesn't seem to be any evidence that the network had been beefed up in any way to prevent the problem, or confine the consequences to the area where the problem first kicked in.
South Australia bought the world's first grid scale battery in 2017 because they'd been having grid stability problems. They anticipated further problems by doing something that made them less likely to show up again.
--
Bill Sloman, Sydney