Transcript
Irene: I was having a normal day. My day starts at 7 a.m. I start working on my computer because I work from home in Seville in the south of Spain. And at 12.30, around that time, I realized there is no internet. So, I restart the router. And the router is also not working. So, I check with my roomie. She also didn't have internet.
Charli: It’s April 28, 2025. And something strange is happening.
Irene: And then we check the light of the house and the light was not working. So, we go out into the corridor to check the light and there was also no light...
The power’s out. Irene is not sure why, though. So, she does that thing most southern Spaniards do when something’s up – it’s a kind of ‘balcony groupthink’.
Irene: We went out to the balcony because there is a lot of communication with the neighbors from balcony to balcony. It's a very narrow street and there is like old people living across so we always check how they are and how they feel. And one of the grandmas was already in the balcony checking and she was asking like 'Vecino, ¿qué pasa? ¡estoy sin luz!’ - saying, “neighbor, what's going on? I'm without light!”
Turns out, it’s not just Irene’s building that’s lost power. News starts coming in that her neighbors in all directions are ‘without light’. And some of them have some interesting theories as to why.
Irene: There is a bar below my place that is always full with neighbours and even if it was 12:30 they were already there drinking some beers and some coffees and so they were chatting and laughing and saying like ‘¡Son los rusos quienes nos desconectan de la electricidad!’ ... ‘These are the Russians cutting off the electricity supply!’
And others were just like, “The most important is that we still have cold beer.” Like, "Don't touch our cold beer!”
As it turns out, it wasn’t Russia attacking Europe and cutting off the cold beer supply. It was a massive, country-wide blackout – across Spain, Portugal and parts of southern France. All of a sudden, like the flick of a switch, 60 million people were without power. It was the most severe blackout Europe has seen in the last two decades.
Irene: ...you don't have food, you don't have water, you don't have air conditioning or heating.
Trains came to a halt. Elevators froze. Traffic lights went out. Homes lost everything from fridges to personal oxygen machines. Hospitals cancelled non-urgent procedures and fired up the generators to continue urgent care.
Irene: We started realizing how many things are dependent on energy that we are not aware in the daily life…
My main concern was like, ok, I need to reach out to my family and see if they are all safe... luckily there were some moments of phone connection.
I reached my mom, who works at a school. She said everything was fine. All the parents were in a bit of a crisis, of course. But everyone was safe.
Pilar: “The only information we received came from people arriving from outside, telling us the city was in chaos…”
For more than 10 hours, the Iberian Peninsula sat in the dark. What on Earth had caused a power failure of this scale?
Irene: So, in my case, maybe because I'm a journalist as well, the first thing I thought is like, don't let yourself go with rumors because we know how misinformation... how harmful that is and how dangerous it can be.
Irene was right - it was too early to tell. But it didn’t take long for rumors to start spreading, and the blame game to begin: A Russian cyberattack. Terrorism. A solar storm. An “atmospheric vibration”. Too much wind and solar. Too much nuclear. Not enough nuclear…
But what if I told you, it was none of those single things that ultimately broke the grid, but something much bigger and much messier?
Hey, I’m Charli Shield. Co-host of Living Planet.
Recurring miniseries jingle
Last week, in part one of this miniseries, we were in Morocco - hearing about the promise and the politics of renewable energy in a place with lots of sun and not much capital. If you haven’t heard that one yet, it’ll still make sense to start with this episode, but I do recommend going back and taking a listen when you’re done with this one.
This week, in part two of The Switch, we’re exploring the other side of the energy coin: transmission. How the way we move electricity, not just make it, is holding things up. And the Iberian blackout is a good place to begin. Because the day’s chaos has highlighted some of the biggest cracks threatening grids across Europe and slowing down cleaner, cheaper power flow.
So, what actually happened that day?
Marcial: This is a very peculiar case in the history of blackouts in the world.
This is Marcial Gonzalez. He’s an electrical engineer based at the University of Carlos Tercero in Madrid.
Marcial: Because one of the main problems came from the voltage control. And this is something very unique and very unusual.
In the wake of the blackout, Marcial’s phone started blowing up with journalists wanting to know what went wrong. So, he tells me he’s pretty used to explaining this.
Marcial: We already know exactly what happened. Then we have to ask why that happened, that will come afterwards, but at least today we know exactly what happened and it's these voltage problems.
“Voltage problems”. According to the factual report released by the European grid operators’ expert panel, several things happened to trigger these “voltage problems”. One of which was sudden changes in power flow.
Marcial: All the morning there was some instabilities in the electrical grid produced by the interconnections with countries in Europe.
Why these happened, they still don’t know, but to calm them, the Spanish grid operator adjusted a few things - including dialing down electricity exports to France. That did help manage the flow. But it also caused the voltage to spike.
Marcial: So it was a problem that was getting bigger and bigger and bigger and bigger until suddenly generators started to disconnect…
For an electrical grid to function, voltage has to stay within tight limits. Not too much, not too little. In this case, when it surged on February 28, 2025, energy transformers and power plants automatically shut themselves off.
Marcial: and suddenly all the system was collapsing.
Most blackouts are caused by frequency problems, not voltage, Marcial says. Thie Iberian blackout was the first ever voltage-driven power collapse of this scale in Europe’s history.
Marcial: And because the nature of this, event was very unique, the system was not really prepared for reacting to this collapse. And finally, that led to the full blackout.
News collage
These were some of the headlines and sentiments amid a wave of misinformation doing the rounds on the internet in the wake of the Iberian blackout.
A lot went wrong that day to cause the outage. But, when you look at the facts, there is nothing to suggest that it was caused by too much solar or wind, Marcial explains.
Marcial: Many people were saying that one thing that may cause the blackout is that the system was operating with high penetration of renewable energy sources.
Spain runs on nearly 50 percent solar and wind electricity. That is some of the highest in the world. But the high amount of renewables alone did not cause the power outage. Firstly, Marcial points out, there had been even more solar and wind generation in the days leading up to the blackout.
Marcial: …and nothing happened. So we cannot expect renewables to introduce such a big perturbations in the system.
Secondly, there were the claims that the blackout was caused by a lack “inertia” from wind and solar. But this idea has also been disproven. Here’s why: so, in this instance, “Inertia” is basically what keeps something moving once it’s been set in motion – like the spinning wheels of a bike, for example. Coal and gas plants use giant turbines that store this momentum, whereas wind and solar don’t provide much of it. And because the electrical grid needs electromagnets to spin at the same speed at all times – so, 50hz in Europe – even small lapses in this speed can throw the whole system off. So the claim was, that without enough inertia because of the high penetration of wind and solar, the grid couldn’t stabilize frequency issues. But, as we’ve already learned, this blackout was caused by voltage issues, not frequency issues. Spain’s main grid operator, Red Electrica, confirmed in an official report that low inertia was not to blame for the power outage.
Marcial: And today we know that this was very, very unfair and of course, totally unaccurate.
A lot of people was blaming renewables because it was simpler. It was very easy to understand. It was very easy to develop this argument and a lot of people was buying it.
A similar response was seen in Texas in February 2021, after a massive power outage led to the deaths of more than 200 people.
News collage
Critics were quick to pin the blame on wind power. But investigations later revealed that it was primarily caused by gas plants shutting down due to abnormally freezing temperatures. And since then, Texas’ new grid operator says battery storage from solar and wind has actually helped protect the system from power outages.
Investigations into exactly why the voltage issues occurred and sparked a blackout are ongoing. The European grid operators’ expert panel is expected to release its final report on the causes in 2026. Meanwhile, Spanish Prime Minister Pedro Sanchez has said it’s clear that it cannot ever be allowed to happen again11.
What experts have concluded so far is that Spain’s grid needs to be “more resilient” and better managed. And the issues revealed don’t just apply to Spain – they point to deeper, Europe-wide cracks in the system. In fact, across Europe, more than 1700 GW worth of renewable and hybrid projects are stuck waiting for a grid connection. That’s more than three times the capacity required to meet the EU’s 2030 climate targets
Lizzie: It's a whole messy situation.
Elisabeth Cremona is a senior energy analyst at Ember; an independent energy think tank that does research on the renewable energy transition15. She’s on their Europe team and she's based in Malta.
Lizzie: If you want my very honest opinion, I think the cause is the fact that the grid has not been prepared or has not been invested in in the way needs to have been.
In other words, the blackout wasn’t caused by too much change too fast – but quite the opposite. Years of neglect of some critical infrastructure that everything else depends on.
But before we go any further, I thought it might be helpful to be able to picture ‘the grid’ if you don’t have something in your mind’s eye already. I asked Elisabeth if she had a good metaphor.
Lizzie: So you drive along a highway and then you get off and you go along go a suburban road towards your house and that's exactly the way the power system works as well. So you have super huge generators. So whether it's wind and solar, gas, nuclear, they are all along the highways, the transmission system, but then for that power to get to your house, it has to kind of turn off and go down into the smaller roads and get to your house. So that's the distribution system, the transmission system. And all countries across the world work in this way.
And now back to that lack of investment…
Lizzie: In Spain there's an actual legislative cap on how much you can spend on the power grid and it's 0.86% of your GDP every year.
Since the Iberian blackout, which is estimated to have wiped about 1.6 billion euros or 2 million US dollars off of Spain’s GDP, the Spanish government has decided to somewhat increase this cap on grid spending. Over the past five years, Spain has only spent 30 US cents to upgrade its grid for every dollar it has put into renewables. That‘s the lowest ratio of any European country.
Lizzie: And that's not just not the way it works for power grids, right? You need a strategy. You need to figure out the best way, the most cost efficient way. But it can't just be capped at a random percentage of your GDP.
And that's left it without some critical gear that other countries use to avoid blackouts.
Lizzie: …one of the things that really struck me outside of the factual report is after the blackout in July, so one and a half months after the blackout, the Spanish government approved the grid operator to install what they call synchronous compensators on the grid in Spain. And these are basically units that provide dynamic voltage control on the grid, which was precisely the problem, it seems, of the blackout, the ultimate cause of the blackout.
If, like me, you need some help here: a “synchronous compensator” is basically a giant spinning machine that helps manage voltage. It stabilizes grids by either generating power if there’s too little, or absorbing excess power if there’s too much. Many energy experts believe that if Spain had enough of these machines, the Iberian blackout could have been avoided.
Lizzie: So the fact that, after the blackout, they decided that for the first time that they need to install these synchronous compensators... there was clearly some kind of lack of consideration of how you operate a safe and secure power system, which is ultimately the remit of the transmission system operator.
And there are other systems-level reasons Europe has struggled to invest in its grids. One of them has to do with how most grids are governed.
Elisabeth says there’s a lot of room for reform here. A good place to start would be separating who plans the grid from who operates it – something they’ve recently done in the UK.
Lizzie: They've now got grid planning done by an independent system planner.
And that means decisions about updating and modernizing the grid are not tied to profit. When grid planning happens inside the same company that owns and operates the wires, it often incentivizes them to stick to the system they already make money from – and that is usually a lower-demand, fossil-fueled system. Because they can often make more money by limiting competition from new energy providers – good for shareholders, not for the public. The UK now has a fully independent public body in charge of planning its energy system - and a separate company for operating and maintaining the grid.
Lizzie: They’ve already made that change, which, again, I think is really great. We’re already seeing huge advancements in the way that they plan and look at the development of their grid. But I do think that that will sadly be a harder fight in European countries simply because you have the problem of big incumbents who have a lot of leverage. They own the entire grid and it's probably within their interests to maintain control over how their infrastructure develops. So it might be quite difficult politically to get the gas and electricity, TSOs to agree to hand over the planning of their infrastructure to an independent operator, even though that is without doubt the most cost-effective way you can actually plan your infrastructure.
How these TSOs, or transmission system operators, work ultimately depends on national governments. And currently, only five European countries have given their energy regulators an explicit directive to deliver net-zero – and that will shape how fast they can push change through the system.
By 2040 - so in the next 15 years - Europe plans to jump from getting 20% of its energy from electricity to 50%. That will require massive, rapid upgrades.
Luckily, there are also ways grid planners can move more electricity around already.
Lizzie: The most conventional way is just having more power lines. That's really simple in a sense because it's what's normally done.
Really simple, but also really slow. New transmission lines can take 12-15 years to plan and build - time that Europe doesn’t really have.
Lizzie: But that does involve a huge infrastructure build, which is quite costly and also maybe not the most efficient way to go about it, especially because we're looking at a huge change in the next 15 years.
That’s where “non-wire based solutions” come in, Elisabeth explains. A bunch of these are just about smarter planning and squeezing more out of the existing electricity system.
Lizzie: So things like putting more batteries on your grids, incentivizing consumers to actually use electricity at different times, so if you go home at 7pm, whether you charge your car at 7pm or 2am, makes no difference as long as you can drive off the next morning, and having a system where you get some automated program that will actually choose when is best to charge your car, both for the power grid stability but also for your bank account.
Take a recent example from Australia. The government has recently announced it will offer residents three hours of free electricity every afternoon. Thanks to its extensive buildout of solar, energy from the sun is now flooding the system at that time of day and driving down wholesale prices. With this policy, the government is hoping to nudge people to use power when it’s most abundant.
And then there are other ways to make the grid we’ve got now work even harder.
Lizzie: So, one very commercially available solution is what they call dynamic line rating, which is when you stick a bunch of sensors along a power line in order to better monitor the temperature fluctuations.
Usually, power operators limit how much electricity can flow through a line to avoid overheating. But currently, they do this blindly - without knowing the exact temperature of the power line at any given time. With sensors, they can see the exact live temperature and potentially push more power through.
Lizzie: You can increase immediately your capacity by 40 percent in some cases. So you're talking about a huge increase in capacity from just sticking a bunch of temperature sensors along a line.
And there’s another ‘solution’ to grid bottlenecks that often gets overlooked. It’s not as easy to picture as a giant spinning turbine or a transmission line, but Marcial says it’s just as important.
Marcial: The investments should go everywhere on the grid, not only in physical things... but also in building new regulations or investing or learning how the electrical grid works with the actual regulations and with future regulations.
Grid operators ultimately work within the boundaries set by regulations. And often, those regulations are designed for an old, outdated system. Not for a clean, distributed and flexible system. Marcial says Spain hasn’t updated some of its key energy regulations in more than two decades.
Marcial: And if we look at how electrical grids were 20 years ago, the things were much, much more different. So we need also to speed up energy transition that way. And it's something that was very, very clear after the Spanish blackout.
We'll be back in just a moment.
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From Denmark to California to South Australia, solar and wind power are already proving to be huge contributors to a reliable grid.
Lizzie: We have very indisputable evidence of the benefits of renewables, specifically in Spain. And this is regards electricity prices, which is something I think almost everyone cares about.
Back in 2019, Spain’s electricity was some of the priciest in Europe. But by early 2025, they were a third lower than the European average – now they’re some of the lowest wholesale electricity prices in Europe.
Lizzie: And that is solely linked to the expansion of wind and solar across Spain in those years. In fact, if we compare them to other major countries such as Germany, Italy, the UK... Spain was actually the only one that managed to split its power prices from the price of gas and that's really why it saw this drop in electricity prices.
Those prices are expected to continue dropping as more wind and solar come online. And the better the power grid is prepared for more renewables, the sooner those savings will come.
Lizzie: So now there's a choice to be made if you want to continue with that and drive down power prices and actually reap the benefits. Or if you want to revert and go back to depending on gas power prices and their various fluctuations.
Fluctuating gas prices, higher energy bills, lost investment, energy instability and delayed climate action – those are the costs of failing to update the grid, experts warn.
Engineers like Marcial say this is a complex task, but it’s more than possible – and pretty urgent.
Marcial: We have to think nowadays of the electrical grid like a puzzle. Like a puzzle where all the pieces are different and we need to find a way to connect each other. We need to design regulations to connect each other better. We need use the technology that we have to connect all those pieces because we have to remember that this is also about energy transition. So we need the energy transition to lower our carbon emissions.
So, generation is one thing. Transmission is another. But once those pieces of the puzzle are in place, what’s still standing in the way? And... what’s possible? Next week, in the final part of The Switch, we want to tie some of these threads together - in a conversation with Bill McKibben, the environmentalist and writer who’s been covering this crisis for 40 years. I'm asking him why the transition keeps stalling - but also, why he feels like this moment is different.
“Humans have made their way on this planet for 700,000 years by setting things on fire. And now we don't really need to. Now we have to figure out how to make the transition as quickly as possible to powering ourselves largely from the large ball of burning gas that the good Lord was kind enough to hang 93 million miles above our heads.”
That’s coming up next week in Part 3 of this special miniseries. I’m Charli Shield. This episode was written and produced by me. It was edited and mixed by Neil King. Our studio technician was Simon Berkhahn.
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