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We're talking about Spain. How bad could a winter really be?

In Germany a few months prior saw CCC publishing a method for destabilizing energy grids using radio waves a cheap hardware: https://media.ccc.de/v/38c3-blinkencity-radio-controlling-st... and presented an attack vector to which most infrastructure in Europe is exposed.

About 4 hours before the grid collapse on the 28th of April 2025 was recorded the largest purchase of Monero in the past 3 years (to remember: monero is coin of choice for special operations), making it surge +40% in 24 hours. The initial Spanish reports mentioned conflicting power information from dozens of locations at the same time which is consistent with a sequential attack using the blinkencity method so the grid itself is forced to close down.

It's like the Swiss Cheese model where every system has "holes" or vulnerabilities, several layers, and a major incident only occurs when a hole aligns through all the layers.

https://en.wikipedia.org/wiki/Swiss_cheese_model

> See, for instance, the space shuttle O-ring incident

That wasn't really a result of an alignment of small weaknesses though. One of the reasons that whole thing was of particular interest was Feynman's withering appendix to the report where he pointed out that the management team wasn't listening to the engineering assessments of the safety of the venture and were making judgement calls like claiming that a component that had failed in testing was safe.

If a situation is being managed by people who can't assess technical risk, the failures aren't the result of many small weaknesses aligning. It wasn't an alignment of small failures as much as that a component that was well understood to be a likely point of failure had probably failed. Driven by poor management.

> Fukushima

This one too. Wasn't the reactor hit by a wave that was outside design tolerance? My memory was that they were hit by an earthquake that was outside design spec, then a tsunami that was outside design spec. That isn't a number of small weaknesses coming together. If you hit something with forces outside design spec then it might break. Not much of a mystery there. From a similar perspective if you design something for a 1:500 year storm then 1/500th of them might easily fail every year to storms. No small alignment of circumstances needed.

It usually starts with a broken coffee machine.

It's lack of experience managing variability, not variability itself.

Wind and solar are very far from dead, but they do need some adjustments - as the report makes clear.

Which on some level is exactly "what the bosses and politicians want to hear"

When it's everybody's fault it's nobody's fault.

There are non-battery buffers available too--I recently got rooftop residential solar installed, and learned that my area is covered by a grid profile requiring that the solar system stay online through something like 60 +/- 2Hz before shutting down completely, and ramping down production linearly beyond a 1Hz deviation or so. The point is to avoid cascading shutdowns by riding through over/undersupply situations, whereas an older standard for my area would have the all solar systems cut off the moment frequency exceeded 60.5Hz (which would indicate oversupply from power plant generators spinning faster via lower resistance).

In my system's case, switching to this grid profile was just a software toggle.

One problem that happened here is the _voltage_ spikes as the synchronous generation went away. Voltage _spikes_ on generation going away seem insane, but it's a real phenomenon.

The problem is that the line itself is a giant capacitor. It's charged to the maximum voltage on each cycle. Normally the grid loads immediately pulls that voltage down, and rotating loads are especially useful because they "resist" the rising (or falling) voltage.

So when the rotating loads went away, nothing was preventing the voltage from rising. And it looks like the sections of the grid started working as good old boost converters on a very large scale.

In this very specific case, battery storage would not have helped (in fact, it would have worsened the problem). One of the issues in the failure is renewables, but not because of intermittence. It's because of their ~infinite ramp and them being DC.

Anything that's not a spinning slug of steel produces AC through an inverter: electronics that take some DC, pass it through MOSFETs and coils, and spits out a mathematically pure sine wave on the output. They are perfectly controllable, and have no inertia: tell them tout output a set power and they happily will.

However, this has a few specific issues:

- infinite ramps produce sudden influx of energy or sudden drops in energy, which can trigger oscillations and trip safety of other plants

- the sine wave being electronically generated, physics won't help you to keep it in phase with the network, and more crucially, keep it lagging/ahead of the network

The last point is the most important one, and one that is actually discussed in the report. AC works well because physics is on our side, so spinning slugs or steel will self-correct depending on the power requirements of the grid, and this includes their phase compared to the grid. How out-of-phase you are is what's commonly called the power factor. Spinning slugs have a natural power factor, but inverter don't: you can make any power factor you want.

Here in the spanish blackout, there was an excess of reactive power (that is, a phase shift happening). Spinning slugs will fight this shift of phase to realign with the correct phase. An inverter will happily follow the sine wave measured and contribute to the excess of reactive power. The report outlines this: there was no "market incentive" for inverters to actively correct the grid's power factor (trad: there are no fines).

So really, more storage would not have helped. They would have tripped just like the other generators, and being inverter-based, they would have contributed to the issue. Not because "muh renewable" or "muh battery", but because of an inherent characteristic of how they're connected to the grid.

Can this be fixed? Of course. We've had the technology for years for inverters to better mimic spinning slugs of steel. Will it be? Of course. Spain's TSO will make it a requirement to fix this and energy producers will comply.

A few closing notes:

- this is not an anti-renewables writeup, but an explanation of the tech, and the fact that renewables are part of the issue is a coincidence on the underlying technical details

- inverters are not the reason the grid failed. but they're a part of why it had a runaway behavior

- yes, wind also runs on inverters despite being spinning things. with the wind being so variable, it's much more efficient to have all turbines be not synchronized, convert their AC to DC, aggregate the DC, and convert back to AC when injecting into the grid

Nuclear has the same issue as (unpredictable) renewables, it is incapable of cost efficiently following the demand curve. As a result, just like renewables, it requires a form of dispatch-able power to complement it (gas, batteries, etc). Solar and nuclear fill the exact same role in a balanced grid - cheap non-dispatchable power.

Or at least nuclear would if it was cheap, but since its costs haven't fallen the same way that the costs of other energy did... well new nuclear buildout really doesn't have a good role at all right now, it's just throwing away money.

Solar and nuclear complement eachother fine - because their shortfalls (darkness for solar, high demand for nuclear) are mostly uncorrelated... a mix of non-dispatcahble power with uncorrelated shortfalls helps minimize the amount of dispatchable power you need... but batteries have made it cheap enough to transform non-dispatchable power to dispatchable power that nuclears high costs really aren't justifiable.

Nuclear has a hard time existing in a net with dominant renewables during most of the year. Down-regulating nuclear absolutely kills its profitability. What you want is power plants with low capex that can be profitable with just a few hundred hours at full capacity per year. For example you can burn hydrogen.

Plus, related I think (storage), you do not want to put hydroelectric in water reservoirs targeted to population consumption, as you could find out one summer that the reservoirs are empty, the result of such water being used with the intention of generate electricity, or even used as inertial stabilizer for renewables.

This is the moment were at the news you read "There's a drought because it isn't raining" and similar excuses, when in reality your five years of water's reservoirs become reduced to half -or one third- due they focused the electricity production over the population real water demand.

I mean, hydroelectric needs at least two level’s reservoirs, one to generate electricity (or even exclusive two level's reservoirs with water pumps for this), and the next one, absolutely untouchable by the electric companies, targeted as water storage for the population/agriculture, the classic more than five years reservoir, for real.

Was the Nuscale cost estimate somehow worse than AP1000 or EPR(2)? That seems very unlikely to me given the history of those programs.