Entso-E final report on Iberian 2025 blackout

(entsoe.eu)

90 points | by Rygian 4 hours ago

7 comments

  • singhrac 1 hour ago
    I think people underestimate how valuable these reports are, so I’m very glad that detailed investigation is done here. Every major grid operator around the world is going to study this and make improvements to make sure this doesn’t happen on their grid.

    In a lot of ways it’s like investigations into airplane crashes.

  • algoth1 2 hours ago
    As someone who lived through the blackout it was wild. I felt back into the pre-internet, pre-smartphone era. It was pretty cool actually. The rumor mill spread so fast that Within hours the official word on the street was that we were getting hacked by a foreign military and people were joking that we had nothing of interest to be conquered xD
    • madaxe_again 1 hour ago
      I didn’t even know about it until the next day - totally off grid, and starlink for internet access - and no mobile signal where we live to give it away either.
    • pfortuny 1 hour ago
      The hack thing spread wildly, indeed. Weird experience.
      • nunobrito 5 minutes ago
        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.

  • darkwater 2 hours ago
    The fact that there is not a single root cause but several ones makes me instinctively think this is a good report, because it's not what the "bosses" (and even less politicians) like to hear.
    • red_admiral 30 minutes ago
      Yes, a lot of modern engineering is good enough that single-cause failures are very rare indeed. That means that failures themselves are rare, but when they do happen, they're most likely to have multiple causes.

      How to explain that to non-engineers is another problem.

    • drob518 2 hours ago
      Frequently, when you see these massive failures, the root cause is an alignment of small weaknesses that all come together on a specific day. See, for instance, the space shuttle O-ring incident, Three-Mile Island, Fukushima, etc. These are complex systems with lots of moving parts and lots of (sometimes independent) people managing them. In a sense, the complexity it the common root cause.
      • linuxguy2 1 hour ago
        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

        • Ringz 1 hour ago
          I use this model all the time. It's very helpful for explaining the multifactorial genesis of catastrophes to ordinary people.
          • anonymars 1 hour ago
            Also perhaps worth a read:

            https://devblogs.microsoft.com/oldnewthing/20080416-00/?p=22...

            "You’ve all experienced the Fundamental Failure-Mode Theorem: You’re investigating a problem and along the way you find some function that never worked. A cache has a bug that results in cache misses when there should be hits. A request for an object that should be there somehow always fails. And yet the system still worked in spite of these errors. Eventually you trace the problem to a recent change that exposed all of the other bugs. Those bugs were always there, but the system kept on working because there was enough redundancy that one component was able to compensate for the failure of another component. Sometimes this chain of errors and compensation continues for several cycles, until finally the last protective layer fails and the underlying errors are exposed."

      • roenxi 31 minutes ago
        > 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.

      • amelius 2 hours ago
        It usually starts with a broken coffee machine.
    • OgsyedIE 2 hours ago
      There are ways to aggregate these into a single resilience score for policy makers with only moderate loss of detail but it's unpopular.
    • ragebol 2 hours ago
      Yep, sounds like "This was bound to happen at some point"
      • cucumber3732842 2 hours ago
        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.

        • darkwater 31 minutes ago
          In some ways, yes, but yet it's what reality is. There was probably some last factor kicking in that triggered the cascade, but there were probably many non-happy-paths not properly covered by working backup/fallback strategies. So a report could totally still tell "it's X fault", pointing the finger there. Government would blame the owner of X, some public statement about fixing X would be made and then the ones working in the field should internally push toi improve/fix their own (reduced) scope.

          I don't know what will come of this report in the next months/years, I will keep an eye on it though, since I live in Spain :)

        • drob518 2 hours ago
          Exactly.
  • wedg_ 17 minutes ago
    I was supposed to fly home from Santiago de Compostella when the blackout happened. Me and my girlfriend had checked out of our hotel and headed to the bus stop to take the bus to the airport. The blackout had already started but we didn't realise (in hindsight, I do remember the pedestrian crossing not working. But I didn't think much of it). Anyways our flight was cancelled and it was clear we needed somewhere to stay the night.

    I immediately rebooked the same hotel, but when we got back there the receptionist had left so you had to check in over the phone instead. Except WhatsApp wasn't working. Then mobile data went down. And before long we were walking through the old town going hostel to hostel looking for a place to sleep, as everything got darker and darker (due to the lack of powered street lighting). The old town in almost pitch black was pretty scary!

    We ended up breaking back into the hotel, borrowing a bunch of towels from a laundry cart in the hallway and sleeping in this lockable room we found in the basement.

    Besides that somewhat stressful part, it was a really strange but fun experience to see the city without power: no traffic lights, darkened shops with lots of phone lights, cafés still operating just with only outdoor seating and limited menus, the occasional loud generator, and most of all the people seemingly having a great time in spite of it.

    I would've loved to have stayed out all night exploring the city, but finding somewhere to sleep that night was a bit more pressing!

  • jacquesm 1 hour ago
    472 pages. That's going to be a nice bit of reading this weekend. It is very nice to see such a comprehensive report as well as the fact that it was made public immediately.
  • throw47452955 2 hours ago
    [dead]