Some Mondays are worse than others, but April 28 2025 was particularly bad for millions of people in Spain and Portugal. Starting just after noon, a number of significant grid oscillations occurred which would worsen over the course of minutes until both countries were plunged into a blackout. After a first substation tripped, in the span of only a few tens of seconds the effects cascaded across the Iberian peninsula as generators, substations, and transmission lines tripped and went offline. Only after the HVDC and AC transmission lines at the Spain-France border tripped did the cascade stop, but it had left practically the entirety of the peninsula without a functioning power grid. The event is estimated to have been the biggest blackout in Europe ever.
Following the blackout, grid operators in the affected regions scrambled to restore power, while the populace tried to make the best of being plummeted suddenly into a pre-electricity era. Yet even as power gradually came back online over the course of about ten hours, the question of what could cause such a complete grid collapse and whether it might happen again remained.
With recently a number of official investigation reports having been published, we have now finally some insight in how a big chunk of the European electrical grid suddenly tipped over.
Oscillations
Electrical grids are a rather marvelous system, with many generators cooperating across thousands of kilometers of transmission lines to feed potentially millions of consumers, generating just enough energy to meet the amount demanded without generating any more. Because physical generators turn more slowly when they are under heavier load, the frequency of the AC waveform has been the primary coordination mechanism across power plants. When a plant sees a lower grid frequency, it is fueled up to produce more power, and vice-versa. When the system works well, the frequency slowly corrects as more production comes online.
The greatest enemy of such an interconnected grid is an unstable frequency. When the frequency changes too quickly, plants can’t respond in time, and when it oscillates wildly, the maximum and minumum values can exceed thresholds that shut down or disconnect parts of the power grid.
In the case of the Iberian blackout, a number of very significant oscillations were observed in the Spanish and Portuguese grids that managed to also be observable across the entire European grid, as noted in an early analysis (PDF) by researchers at Germany’s Friedrich-Alexander-Universität (FAU).
This is further detailed in the June 18th report (direct PDF link) by Spain’s Transmission System Operator (TSO) Red Eléctrica (REE). Much of that morning the grid was plagued by frequency oscillations, with voltage increases occurring in the process of damping said oscillations. None of this was out of the ordinary until a series of notable events, with the first occurring after 12:02 with an 0.6 Hz oscillation repeatedly forced by a photovoltaic (PV) solar plant in the province of Badajoz which was feeding in 250 MW at the time. After stabilizing this PV plant the oscillation ceased, but this was followed by the second event with an 0.2 Hz oscillation.
After this new oscillation was addressed through a couple of measures, the grid was suffering from low-voltage conditions caused by the oscillations, making it quite vulnerable. It was at this time that the third major event occurred just after 12:32, when a substation in Granada tripped. The speculation by REE being that its transformer tap settings had been incorrectly set, possibly due to the rapidly changing grid conditions outpacing its ability to adjust.
Subsequently more substations, solar- and wind farms began to go offline, mostly due to a loss of reactive power absorption causing power flow issues, as the cascade failure outpaced any isolation attempts and conventional generators also threw in the towel.
Reactive Power
Grid oscillations are a common manifestation in any power grid, but they are normally damped either with no or only minimal interaction required. As also noted in the earlier referenced REE report, a big issue with the addition of solar generators on the grid is that these use grid-following inverters. Unlike spinning generators that have intrinsic physical inertia, solar inverters can rapidly follow the grid voltage and thus do not dampen grid oscillations or absorb reactive power. Because they can turn on and off essentially instantaneously, these inverters can amplify oscillations and power fluctuations across the grid by boosting or injecting oscillations if the plants over-correct.
In alternating current (AC) power systems, there are a number of distinct ways to describe power flow, including real power (Watt), complex power (VA) and reactive power (var). To keep a grid stable, all of these have to be taken into account, with the reactive power management being essential for overall stability. With the majority of power at the time of the blackout being generated by PV solar farms without reactive power management, the grid fluctuations spun out of control.
Generally, capacitors are considered to create reactive power, while inductors absorb it. This is why transformer-like shunt reactors – a parallel switchyard reactor – are an integral part of any modern power grid, as are the alternators at conventional power plants which also absorb reactive power through their inertia. With insufficient reactive power absorption capacity, damping grid oscillations becomes much harder and increases the chance of a blackout.
Ultimately the cascade failure took the form of an increasing number of generators tripping, which raised the system voltage and dropped the frequency, consequently causing further generators and transmission capacity to trip, ad nauseam. Ultimately REE puts much of the blame at the lack of reactive power which could have prevented the destabilization of the grid, along with failures in voltage control. On this Monday PV solar in particular generated the brunt of grid power in Spain at nearly 60%.
Not The First Time
Despite the impression one might get, this wasn’t the first time that grid oscillations have resulted in a blackout. Both of the 1996 Western North America blackouts involved grid oscillations and a lack of reactive power absorption, and the need to dampen grid oscillations remains one of the highest priorities. This is also where much of the criticism directed towards the current Spanish grid comes from, as the amount of reactive power absorption in the system has been steadily dropping with the introduction of more variable renewable energy (VRE) generators that lack such grid-stabilizing features.
To compensate for this, wind and solar farms would have to switch to grid-forming inverters (GFCs) – as recommended by the ENTSO-E in a 2020 report – which would come with the negative effect of making VREs significantly less economically viable. Part of this is due to GFCs still being fairly new, while there is likely a strong need for grid-level storage to be added to any GFC in order to make especially Class 3 fully autonomous GFCs work.
It is telling that five years after the publication of this ENTSO-E report not much has changed, and GFCs have not yet made inroads as a necessity for stable grid operation. Although the ENTSO-E’s own investigation is still in progress with a final report not expected for a few more months at least, in light of the available information and expert reports, it would seem that we have a good idea of what caused the recent blackout.
The pertinent question is thus more likely to be what will be done about it. As Spain and Portugal move toward a power mix that relies more and more heavily on solar generation, it’s clear that these generators will need to pick up the slack in grid forming. The engineering solution is known, but it is expensive to retrofit inverters, and it’s possible that this problem will keep getting kicked down the road. Even if all of the reports are unanimous in their conclusion as to the cause, there are unfortunately strong existing incentives to push the responsibility of avoiding another blackout onto the transmission system operators, and rollout of modern grid-forming inverters in the solar industry will simply take time.
In other words, better get used to more blackouts and surviving a day or longer without power.
Fascinating and really good write up, thanks Maya! would love to see a follow up when the report drops~
no no no this is all wrong. Solar is so much cheaper than nuclear, and the Europeans are extremely enlightened. Obviously they have laws that guarantee that the power grid will remain stable, so something else must have caused this. There’s no way that an entire continent would throw all that money at PV generation, and not build adequate grid storage and reactive power facilities, that would just be silly engineering. It could only happen if something other than engineering was the driving force behind the adoption of PV power, which is ridiculous! What kind of society would allow its infrastructure to be designed by politicians or somesuch, and not actual engineers?
“allow its infrastructure to be designed by politicians or somesuch, and not actual engineers” best comment I have even read. Welcome to EU Aleksclark!!
It is not new. Scott Manley recently commented that the Space Shuttle was designed by politicians.
I can appreciate your post is written sarcastically but… Nuclear really would be cheaper if it weren’t burdened with excessive red tape, Sizewell C being put up in the UK was forced to write up a 400,000 page “environmental impact report”, another related example is that Germany, known for being noweher near any seismically active oceans of the kind which caused the Fukushima accident, panicked in response to Fukushima and then shut down all its nuclear plants. Nuclear energy, given it involves big heavy spinning generators of almost exactly the same kind as in coal power stations, would have had the physical inertia needed to limit the oscillations that caused the blackout. A society without a fixation on red tape is much easier, and more desirable, to get used to than regular many-day blackouts.
Oh absolutely. Nuclear without red tape would be cheaper than current PV designs, which omit grid storage. PV with enough grid storage to provide equivalent baseload over 5-year minima would run around 2-3x the cost of nuclear.
nuclear is not the problem, people are. i dont trust people with fission products. and of course, exploding powerplants vs burning pv panels is no comparison.
you could get air and ground travel a lot cheaper if you used less red tape as well.
The first is true, the second is not. Air travel without heavy oversight results is poor maintenance and training, resulting in accidents and delays. We have all the evidence necessary to show this.
An Allie!
Let me explain my plan for trebuchet, wingsuit and parachute commuting.
We’ll have a grid of trebuchets, one throw apart.
I know what you’re thinking…Too much up front, cap cost…
The problem with fission products is if they run a reactor for bombs, they can skip the whole high level enrichment step.
How all the world’s nuclear powers do it.
Including ‘best Korea’, IIRC.
Also how Israel and Japan didn’t do it.
Amazingly, apparently, nobody expects Iran to do it that way.
Not so much a problem with power reactors.
You just cant refuel those fast enough to make bomb goo directly.
I’ve tried…
Digression{
Joke feds, I’m not actually a bond villian building a repromod Czar Bomba, I don’t own a W86, a Mark24 or a prototype Cobalt bomb, I’m not brewing up a Mad Cow/Ebola/Black Death/African Sleeping Sickness cross…
I’d have to get them ALL really really really drunk (Prion x Virus x Bacillus x Parasite).
}I digress…
You’d end up doing isotope separation on plutonium.
Nobody does this…
The chef has prepared a Amuse Buch:
PlutoniumOctoFloride, it will sting the palate a little at first, but give it a chance.
Last years ‘Bob Hope’ certainly is nice.
Down the road from me they are converting a coal plant into a giant UPS for just such an occasion. They are converting the generators into “synchronous condensers”. Basically, giant constantly spinning flywheels with enough inertia to help smooth out temporary fluctuations in the grid. No batteries to maintain. Should be enough to provide the few seconds needed to react to issues.
I worked for a company that had a UPS which while much smaller operated on the same basic principal. Three flywheel based generators. While there was grid power the flywheels would be spun at a constant speed. When grid power was lost, the inertia stored in the flywheels provided about a minute of power, just long enough for the diesel generator to spin up and take over. Again, no batteries to replace every few years.
what about pumped hydro storage ?….it goes from 0 to 1000 MW within 15 sec. !?
True frequency response comes from capacitors or spinning mass, and responds in milliseconds.
Spain has a lot of nuclear, and it is cheap, and it has spinning things.
Except the nuclear is not cheap enough to compete with solar in April, so most of the plants were pulled off line.
Spain should pay the nuclear reactors a frequency response fee. Then they can put a big DC motor on the turbines and spin it at 50Hz.
Blaming all of this on just the solar is stupid and shortsighted. multiple things went wrong and the “wobbles” from the PV plant were basically just the thing that tipped the first dominoes. By all accounts mistakes were made and the grid oscillations observed should never have led to any power dropping out and the first transformer trip that set the dominoes in motion should not have happened. Conditions on the grid created the perfect storm of setting up a grid with little reactive power reserves that then got overwhelmed as even more of that power dropped from the grid. This could have been avoided in several ways and without doubt improvements will be made to grid operation manuals to avoid future occurrences of such perfect storms.
And large PV plants might well be required to install measures to avoid triggering grid oscillations too but that’s not exactly cheap
That’s the whole point, 100% of the point. Building intermittent generation without adequate adequate storage is a political boondoggle.
I hope you are being ironic
It isn’t really the politician that doing the design work, though they share a portion of blame for selling off national essential services and not then controlling the companies. But its largely the bean counters and Suits that seek stupid profits NOW without ever doing the work to remain viable in 5 years – “ah the tax payers will bail us out” or “I won’t be bothered by the service failing, but I do so love massive bonus payments so lets not do all that essential maintenance and upgrading! As that costs money and will hurt our profits this quarter. Then the top executives will take golden handshakes as their business savvy ruins the company or just move on leaving somebody else holding the bag..
See in the UK water companies as well.
Nothing wrong with Solar and Wind, but if you are going to transition from old to new tech you have to actually do it, not make the PR noises that say you are and do some of it for the cameras.
Sure about that? “Here’s a power source that generates power 17% of the time, at pretty much random, you must use it.” is a pretty strong influence on the design. And even then, most people I know, let alone engineers, would say something like “ok, that means we need a LOT of energy storage to smooth things out.” Where do you think the decision to not build that was made?
The fundamental problems: corporate owned governments and easily manipulated voters.
problem in Germany/Europe: the politicians didn’t listen to the experts and declared pumped hydro (and other storage) as consumer. Therefore they have to pay the network fee, which means they lose money when they flatten smaller peaks, and they lose money when they have to wait for higher peak prices while doing nothing. So nobody can afford to invest in grid scale storage…
The decisions on what to build are made at least mostly by the companies that will make profits from them.
The permission to actually use that patch of dirt/sea for wind/solar must be provided by the governments. But the nearest they get to making decisions not to build something is not allowing the company to build that at a particular location. Or I suppose you can argue not tweaking the subsidies away from Oil/Gas towards their desired grid structure to make it more profitable for the company to build what you wish them to build.
More a case of nuclear being too expensive.
Solar is indeed quick and cheap to build, especially in sunny places like Spain.
Their problem is a lack of grid inertia caused by a lack of contracts for grid inertia and frequency stabilisation.
it’s not tho. PV is only cheaper if you don’t include the necessary grid infrastructure to support it, as they did in Spain. Once you account for storage + inertia, nuclear is cheaper per delivered MWH
So, if the PV inverters were a bit smarter than “just follow the grid frequency”, they would effectively be able to dampen the oscillations, instead of amplifying them?
Of course, some protocol would have to be introduced so that the grid operators can effectively control the inverters, and at this point it’s a bit too late to retrofit everything.
You know what’s really crazy? The best way to smooth this out given current tech is probably to overbuild the PV, and use crypto miners to smooth the load.
SOMEWHERE I read a Click Bait Add, about Air Conditioning Systems being the Savoir of PV/Wind Systems.. It would use Interconnected Smart T-Stats Controlled by the Grid Operator, to Increase or Decrease Distributed Loads to Quickly Smooth out the Grid System..
Interesting Idea..
Lets hack that Fix and see what can happen..
Cap
The game theory is wrong for that though. The grid operator is not the person who will be harmed by lack of AC. On the other hand, if a PV operator gets more $$ by mining crypto than selling power to the grid they’ll do it because it’s in their best interest.
Not really the game theory on that AC type concept goes something along the lines of fit these devices and you’ll get a small kickback, reduction rates, etc – some minor fiscal gain, and the amount of AC duty cycle you’ll have lost or overdrive you’ll get amounts to a barely noticeable amount. Once the network is large enough you have dynamic loads to the benefit of everyone – as it is the grid operator that will be harmed should the grid black out, and it is the AC user who is harmed when the grid is dead.
I doubt anywhere in Europe you’d get more money mining crypto than selling to the grid, and probably by a huge margin – but when the grid won’t take any more units from you I guess running the LLM or crypto miner faster…
“So, if the PV inverters were a bit smarter than “just follow the grid frequency”, they would effectively be able to dampen the oscillations, instead of amplifying them?”
UL1741 has this… as usual, there’s a lag for manufacturers to design, test, and pass it, but it provides several grid support functions to combat exactly the problem described in the HaD article.
“Of course, some protocol would have to be introduced so that the grid operators can effectively control the inverters, and at this point it’s a bit too late to retrofit everything.”
Nope, control is done by observing the grid, no further out of band control needed.
https://blog.windurance.com/standards-for-renewable-energy-inverters-understanding-ul-1741sa
I thought there were some attempts to make an out-of-band signalling for load as well. “Wide Area Measurement System (WAMS)” and phase measurement systems and stuff. (Not my field!)
Oh – I should have perhaps worded that better. OOB signalling is still desired as a WANT – it gives feedforward control and more importantly to the utilities, allows accounting in the sense that substation A contributed some measure (say kVARs or Hz, whatever the qty of interest) to the wider network and so is “owed” some recompense depending on agreements between providers….
But when enough distributed generation equipment is installed with UL1741SA and it’s inevitable future revs, that primary control programmed in to every inverter will greatly stabilze the grid. The old model was that the grid is the boss and distributed generators need to cut out at the first sniff of trouble – but as penetration of DG’s increases that becomes self defeating!
Inverters without local storage can (sometimes) push but they can’t pull, which is needed to fully emulate the inertia of a conventional generator. The amount that is technically needed depends on the battery technology, but it’s approximately on the order of 0.5 hours – not because of the operating time on the battery, but because it needs to be able to absorb or emit power on the same scale as the generator it represents without pushing the cells too hard. Otherwise the lifespan of the battery will be reduced and it becomes even more costly to run.
While there are tiny batteries that can supply a lot of power, like LiPOs, these aren’t exactly known for their longevity or safety, or low cost per capacity. Meanwhile, other types pack more energy and are cheaper and safer, but consequently are limited by the current ratings which means that for a VRE plant to suddenly absorb, say 100 MW of extra power, you can’t be pushing it to a tiny battery – you need around 50-100 MWh worth of batteries, and that’s going to cost you millions of dollars to buy and replace every so many years as the cells age and wear out.
That’s the main reason why the VRE and grid operators have been avoiding the topic. As integration levels rise and spot market prices come down by market cannibalization (all solar producers producing at the same time), the profit margins are getting pretty slim to non-existent. The only profit they make is coming from the subsidies which are fixed and capped by the authorities, so making profit is about cutting cost below what the government is willing to pay for the energy.
The downside of course being that without adequate means to stockpile energy, the government will ultimately end up paying it all because the market mechanism breaks. Then there is the part where the costs are minimized by outsourcing the fundamental technology to the far east instead of sustaining local manufacturing and expertise. All this because the government needs to pretend to the public that the system is affordable, to justify the subsidies and the command economy on the energy market that follows, by skipping on important details like minimum levels of grid storage to make the system functional.
Then there is also the political aspect where certain parties want the government to take over the energy market entirely, so they could then dictate energy prices to consumers and steer the money around as they please. It’s called “create the problem only you can solve” method of getting elected.
…Also the Cloward-Piven strategy of intentionally blowing up your own country so you can communistically rule over the ashes, which is obviously in vogue
Exactly the opposite is happening, what are you talking about?
Power pools were the chess move, 30 years ago, to hold off the political twits and let market forces play.
Local utilities didn’t like it, nationals did, as long as it wasn’t in THEIR local area.
Renewable mandates are the current ‘shit in the soup’ for the grid operator.
Fortunately, Spain is an edge case.
They took the hit so the rest of the world can watch and not do what they did.
The Peter Principle and it’s corollaries never sleep.
Power companies and governments are universally run by people operating at their level of incompetence.
At present we do not know the official causes of the problem because the Spanish government does not disclose them in full. The Government alleges internal security issues and the opposition claims that this is just a way to cover incompetence. A European investigation is already under way. In a recent interview, Mira Amaral, a former portuguese Minister of Industry and Energy (graduated in Electrical Engineering, with experience in electricity grid management), mentioned that there is a chance that Spain had carried out an unsuccessful test to verify how the grid reacted without the full support of classical sources (thermoelectric, nuclear).
We also know this has happened before in various places, due to the same reasons speculated here. This is just going to get more and more common.
When you scale up VREs in a hurry and skip over some fundamental stabilization measures because they’re too costly or politically infeasible, you will at some point reach a critical level where the grid is starting to creak at the seams. The number of “close call” events reported by grid operators in the past decade has increased by at least an order of magnitude across Europe.
The first trip will always be a combination of causes and things gone wrong simultaneously – so you can play plausible deniability, and the people responsible will deny the cause for as long as they possibly can. But, play the high wire act with your shoelaces undone and eventually you will go splat anyways.
CleanTechnica has a decent article about it. See my root-level comment in a few minutes. In the meantime, a link to the article (which contains a link to Spain’s 192 page report).
https://cleantechnica.com/2025/06/18/inside-the-iberian-grid-collapse-what-really-went-wrong/
Typical Dude nonsense …
The Inverter does not have to pull, there is sufficient load which constantly pulls. The inverter just has to push more or less energy to effectively push or pull.
Yes it does. That’s what the inertia of a spinning generator does – it works both ways, almost instantly in response to a frequency fluctuation to dampen the oscillation. That’s what it needs to be able to fully emulate the inertia of a conventional generator.
Of course you can add artificial loads to the network otherwise, and that is also something that is done in places though it too costs extra money and isn’t more common because of that. Yes, it is not necessary for this function to be provided by the inverters, but without any local storage they also lack the ability to push more power if they’re not getting more power from the sun or wind at the moment.
You’d be relying on throttling the generators to have that margin, which isn’t done because the operators are getting paid subsidies by every MWh they produce, so they’re pushing it all out whenever they can.
Not always. The loads these days are themselves inverter driven, so they don’t care what the grid frequency is. They just draw constant power, unlike the old spinning loads and generators which draw more power when the grid frequency goes up, and less when it goes down. At least, until they detect a fault condition and then drop off entirely – which makes the oscillation worse.
That last part is the devil in the detail. The system no longer responds linearly to power fluctuations. When the oscillation goes bad enough, it causes a cascading failure.
Also, you might be under-estimating the contribution of the flywheel action of conventional generators.
It’s measured in Gigawatt-seconds. Conventional power plants usually have between 2-7 seconds of inertial response proportional to their nominal power. You need a lot of batteries to match that.
All of this inertia talk aside (complicated topic!) as distributed generation inverters adopt measures like UL1741SA, they will gain something around 3/4 of the capability needed for grid stabilisation in situations like this. You can move the grid V, f, and phase around to raise/lower the voltage, power factor, frequency etc with no storage, no flywheel effect, but with instantaneous reactive power control. Inverters can do this today, many of the big brands like SMA, Enphase, Solaredge, Fronuis alreday have this capability but until it is mandated to be USED, they only do the minimum, because the owner (assuming residential) gets payback only on real power.
I realise i didn’t quite complete the thought. Point is, being an actual generator with inertia might be the ideal, but we can get most of the way there with current tech with no real changes to hardware or software, as evidenced by the fact that a lot of big name inverters already have this capability. What needs to change is policy.
I think you need less batteries as the actual power shifting within a wavelength is done with capacitor banks.
As the UK has found, the amount of battery needed to support Grid Forming Inverters is trivial compared to the amount needed to exploit the arbitrage opportunity. Germany needs about 100GWh to “flatten the duck curve”.
Wow, great summary Maya. It’s interesting to compare this article with other recent ones (search the ‘net for “Iberian blackout”). Those seem to be based on a Spanish gov. summary of the report, and look like the slant was “not enough corrective plants were scheduled, some plants didn’t do what they were supposed to, nothing to do with renewable”. The articles were also pretty thin on details, since the pre-released summary was rather vague.
Based on the actual report, it sure looks like there are fundemental issues that will take some serious money to do right. I’m not making an argument against renewable energy; this is the old “who pays, who profits, how far can we kick the can down the road” dance.
CleanTechnica has a good article on the subject with a slightly different take[1]. It contains a (bad) link to Spain’s 192-page report.
It can be summarised as:
“Rather, it was the result of multiple layers of insufficient planning, inadequate voltage management, and poorly managed grid dynamics. 50% of the allocation of responsibility was to human failures in planning, 30% to legacy generation not performing as it was designed to do, and 20% to renewables exiting the system because they weren’t configured to deal with the scenario, once again a human failure more than a technology failure..
disconnection of several renewable generation facilities, not primarily due to issues inherent to wind or solar power, but rather due to inadequate voltage management and system protections at these facilities..
The report explicitly notes that the majority of tripping occurred at evacuation infrastructure jointly used by multiple renewable generators, facilities designed with fixed power factor control rather than dynamic voltage regulation..
The future, however, clearly belongs to renewables supported by advanced inverter technologies, dynamic voltage stabilization hardware, smart market structures, and robust regulatory frameworks.”
The temptation is always for climate science skeptics to use any grid failure (or EV failure) to blame it on the principle of clean tech, as though these kinds of engineering issues are insurmountable, because they don’t burn multi-million year-old fossils. Put like that, it’s a strange idea to believe that all engineering is fundamentally tied to burning the dead.
Real engineers don’t abandon project requirements every time there’s a glitch (which this was); they create better solutions we can all benefit from. Which is why Spain’s response is correctly, to continue to pursue its renewable energy future.
[1] https://cleantechnica.com/2025/06/18/inside-the-iberian-grid-collapse-what-really-went-wrong/
As proposed, the engineering issues inherent in intermittent power generation ARE insurmountable. Everyone pitches solar and wind as “oh so cheap” because they pitch it without sufficient storage. That’s just not fixable.
Yeah, we did, we call them “nuclear reactors.” They don’t require unobtanium batteries or superconducting transmission lines.
To protect against this sort of fluctuation based problem just needs a few pretty darn cheap effective passive ‘capacitor’ flywheels fitted. But cheap though they are they won’t really make any money as they don’t really work for power trading schemes, so nobody wants to build them. But it doesn’t take much in the way of flywheel mass to damp out that initial change enough the system doesn’t fall over as all the stuff on the grid is given time to react(at least from my reading of the subject, I’d not claim expertise).
You don’t have to have any storage at all to make Wind and Solar really really cheap, but you do need to do something to provide power or cut consumption when they are not working well enough. Which could just be a wider grid of renewable generators, as its always sunny and windy somewhere (Expensive but doable across the EU and perhaps into N.Africa, and Israel but less plausible across the more sparsely populated areas).
Or at the other extreme it could be regular gas, coal, or nuclear that you only ramp up when the sun and wind goes down, in which case all you need storage/grid smoothing wise is enough fast dispatch storage or dynamic load shedding to provide the time for those backup generators to ramp up. The electric is still pretty darn cheap as the wear and fuel consumption on those more conventional backfill power plants is pretty low when perhaps 2/3rd of them are parked entirely most of the time.
Sure, just stop using power, that will work nicely….
see: superconductors referenced in previous comment
So to you, PV is cheap…so long as you build a fully redundant set of power plants. Why even bother with the PV at that point? Just build the nukes, no more transmission loss, no more storage needed, etc.
You do realize the average PV plant manages around 17% duty cycle right?
You really don’t need superconductors to make a wider grid of renewables very viable (though if you can figure out how to do so practically that would be a huge gamechanger). But a large enough mesh distributes the load well by its nature, and is required anyway to connect all the dispersed renewables you’d be adding to make this mesh (at least to some extent). And a mesh like this also keeps the total transmission distances on the whole reasonably low. As all those local renewables that are not working even near peak are still producing something – the weather can be bad for them but it won’t be zero local production, so as we see across Europe already trading for French Nuclear or the Hydro of Norway across fairly significant distances is very viable (as even with current rather old infrastructure transmission isn’t actually that inefficient either).
You already have those power plants, at least in every developed nation – what PV and even Wind does if you want to use it that way is take that previously 100% oil based grid and allow you to go hybrid. And because the per unit cost is so dirt cheap for its lifespan (with solar being way way better than Wind there) it reduces the cost per unit of the whole system. At least if you don’t have a bonkers economic setup with too many competing producers, subsidies and middle-men making a mockery of the potential.
As instead of having to extract, transport, refine, transport and then burn 9000 tonnes of fuel all the time you are only burning 1000 to say 3000 tonnes much of the time. Which saves hugely in costs per unit, and for many nations would reduce if not entirely eliminate their need to tanker in Arab/Russian energy – so no more sudden price hikes when the supplier decides to price gouge as you are so dependent on them…
Not really relevant overall when the highest and lowest moments of PV output generally lines up reasonable well with the natural energy demand fluctuations that humans have, what with most of us sleeping while the sun is down.
It does matter, but just talking total duty cycle doesn’t reflect the way energy is used – the regular powerstations are often massively below full utilisation too – but when its time for the entire nation to put the kettle on all at once in the advert break….
Not really the case. Renewables are affected by weather systems, and weather systems often cover a good chunk of a continent.
It’s only become viable as the price of electricity in Europe has exploded – nearly double since 2010!
No, politically speaking what happens is countries shut down non-renewable generation as it ages, and even if they don’t, they don’t expand non-renewables as their total energy demands grow.
It’s pretty relevant – your example about the kettle for instance is specifically one that would tend to occur during low PV production
Sure, but a grid of the size suggested is well into 3 continents, nearly entirely if not entirely spanning the European, at least across the borders into N.Africa, quite possibly just continuing to creep south as it goes, and potentially across to Israel and the more friendly to the western world neighbours in that region. Plus with huge numbers of wind turbines already in the North sea, various tidal and wave generation ideas, some even in operation at larger than trial sizes it is quite possible to go much further and be well beyond the continental landmass limits!
Also even in the worst possible case you’d see weather systems almost never cover a continent in no sun, but also no wind at all – in general you’ll not get the thick enough clouds to even make a real dent in the average solar output without also ending up with good winds at nearly that scale – becalmed and very thickly cloudy just isn’t the sort of weather to stick around especially over such wide areas.
Neither part of that really seems true to me, the only thing that is definitively true is the new wave of nuclear energy never seems to actually get built, and is something like 30 years behind the promises at least (which is a shame IMO).
I also did very specifically say they were two very extreme options that COULD not SHOULD or even are likely to be taken that avoid the electrical energy storage options (though one could argue the fossil fuel or nuclear options are just very delayed or very very very delayed solar power, so actually just energy storage, being potential energy laid down a long long time ago we are consuming). And both would work to clean up the grid considerably, while also making energy cheaper per unit (at least from a technical cost to produce if not a real world price per unit)
We are talking about Spain. If something can be done mañana, will, and shall be done so, until something breaks. This blackout being a living example.
The report read like a novel. Almost riveting. Dude at Practical Engineering in YT has a word or two about electricity (in fact made a series of videos on the subject) and covered blackouts in one of them, before the spanish blackout.
A really interesting and readable article. Thank you! It did pique my interest in how a power grid works more generally, but the various links led to Wikipedia articles on specific components of a grid which I found hard to understand. So any chance of a more general ‘How Power Grids Work’ article? Or if there is one already, a link to it would be appreciated.
What about this video from Dude at Practical Engineering in YT
https://youtu.be/bbECmVdyWlQ
No wonder they had problems. It’s all running at 50 Hz! :)
Yeah, not a https://en.wikipedia.org/wiki/Highly_composite_number
They should have used 48 Hz.
(Yes, this has exactly as much relevance.)
“Generally, capacitors are considered to create reactive power”. Supercapacitors??? Not something a power engineer would think of first, but, feasible? Cheap enough?
A similar thing happend in the US when a Niagara issue caused a cascade and took out the grid in a large chunk of the US I understand
The interesting thing is that it only happened once. Shows you CAN deal with issues and fix them
For the lobbyists here: Niagara is water power so you can blame it wasn’t nuclear that was the issue.. have fun with your lobbying and your lobby money. Don’t choke on it and wash it before and after any sxual activity.
Oh and as for storage: quite some time ago I read that Germany and some neighboring countries had a joint superconducting ring system project for temporary grid energy storage. Not sure what it is called.
And in the US they also played around with SMES.
https://en.wikipedia.org/wiki/SMES
What always bothered me is how the frequency is measured in a distorted grid voltage ( high ratio of power electronics connected) and what is the inherent measurement error.
Another control variable is the setpoint over time of the third order frequency regulation loop which is supposed to compensate cumulated frequency errors to make the grid again synchronous to UTC.
If 1st and second order loops synchronize on 50.0 Hz and 3rd order needs 50.1, grid oscillations are in mho very likely to occur. I do not know if and how the 3rd order setpoint is communicated to all the other power injectors connected to the grid.
Filter the 50 Hz before measuring.
Time synchronization is done by dedicated power plants, which set the wanted frequency to 50,005 Hz or 49,995 Hz for adjustment. The power/frequency regulation does nothing within a +/-10 mHz band around 50,000 Hz, because most of the fluctuations within this range quickly cancel out themselves, so the two mechanisms don’t work against each other. One could describe it as shifting the tolerance band a little, so the grid time shuffles back to UTC.
Very good article.
I think the quick answer is a couple of 5MWh batteries and a grid forming inverter at every substation.
These do local arbitrage on the distribution network, thereby reducing electricity flow on the transmission network.
They could also flip the local grid onto island mode for a while, and do software controlled black start within seconds, rather than a day.
Blackouts happened in the past and will happen in future no matter the technology. But this brings question how well we are prepared for them? Can every house function without power? Can you cut off from grid and run on your solar panel? Will water (and sewage) keep flowing? How well society is prepared to support each other to survive next 48h?
The longer we have reliable grid the less we are prepared on every possible level.
There is another tool available to manage falling frequency. In the UK, distribution operators are bound by a GC requirement to install relays in their substations which automatically trip demand off as the frequency falls (LFDD). This is intended to shed load to match the generation capacity. This appeared to be present in the Iberian grid, but may have the situation worse once the overvoltage situation worsened. Demand was indeed being shed, but with it, its ability to absorb reactive power. This was nuanced in effectively a single line in the report, but was a significant learning point.
That’s a difficult one: if you trip a substation in an area with a lot of home solar, you may actually shed net power generation instead of load.
Btw loving the Power System stuff!