Yes, I do have more technical information on the likely causes of the Iberian Outage, but please appreciate that I'm already busy communicating with Councillors, my MP and NESO on the issue, and they must take priority over this Forum!
The Spanish grid operators were slower to act than National Grid ESO was six years ago.
In our case, ESO called on two other sources of generation which were then on standby. Both failed, leaving grid frequency to fall to 48.8Hz... ... and ESO implemented widespread Load Shedding across England and Wales to prevent the grid frequency falling further.
Spain tried to retain the wider grid connections for too many seconds.
It was the French who intervened to isolate the rest of mainland Europe and allow just Spain and Portugal to go into blackout.
I totally support you informing councillors MPs and NESO about potential root causes and hopefully they will understand enough to know ‘something must be done’ .
When your time allows I look forward to reading why Iberian grid lacks resilience and why we lack data. I have read a couple of reports about the cascade of load shedding and why it was needed on the Aug 19 power cuts. They are interesting in their different perspectives and also what they don’t say(!)
2kW + Growatt & 4kW +Sunnyboy PV on south-facing roof Solar thermal. 9.5kWh Givenergy battery with AC3. MVHR. Vaillant 7kW ASHP (very pleased with it) open system operating on WC
I wasn’t surprised to read that the Telegraph believes that renewable energy was the problem for yesterday’s Iberian power cuts. Clearly it won’t have helped since it has no inherent inertia, (a technical term for traditional generators having large flywheels that run at nearly a constant frequency).
As usual the FT may have got closer to root cause in their report of power lines subject to overheating and carrying too much power in suddenly very warm air. That caused the frequency to change.
I look forward to finding out eventually to what was really the problem! Our colleague @transparent is usually better informed than the rest of us.
Ok... until Red Eléctrica de España offer their conclusions everyone else is just running on their imaginations. Although I concur that of course the Telegraph and all the usual anti-renewables suspects are going to mine this until the pips squeak.
The funny thing is I just gave a presentation in London that included the Spanish & Portuguese grids a few days ago... great timing! And I have live monitoring facilities for both. Neither blinked all day yesterday so I had a ring-side seat. I'll leave it at that for now. 😁
Coincidently, the other day Spain also achieved a full weekday on 100% renewables.
There's a few points that fed into whatever was the initial cause - the original suspicion was on an 'anomalous atmospheric phenomenon' but now they are working on another technical cause which I'll keep to myself so as not to add to speculation. I dunno.
Spain/Portugal are a combined market with minimal inter-connectors to the rest of Europe. It's technically referred to as 'Islanded'. This serves them incredibly well and allowed them to weather the energy crisis of 2022/23 better than the rest of Europe because they were permitted by the EU to temporarily de-couple from the European market.
This was called the 'Iberian Exception'. Spain wanted to cut the French interconnectors temporarily too but the EU said no. Anyway, they are a mutual market/infrastructure setup with good hydro underpinning too.
Unlike Britain, they have been working on their grid for a long time - building it out and keeping it up to date. I had an amazing little tech lesson with one of their engineers yesterday, which considering what was happening, was extraordinary. Really patient guy.
What I will say is they were super efficient at recovering, it's a huge country with complicated terrain and varying weather conditions. They will learn fast but this will probably twist their arms to facilitate more European interconnectors as 'French donations' helped them out yesterday. (They've been resisting for a long time but the rest of Europe wants a piece of their pie and connections to N Africa).
Spain has superb engineers and the country pulls together extremely well. Yesterday was no exception with deliveries of refreshments direct to trains, hospitals unaffected, and so on.
Plus the PM (Señor Guapo - Mr Handsome 😂) gave public updates throughout the day, 3 Provincias - Andalucía, Estramadura and Madrid went temporarily into emergency powers and the King rolled his sleeves up and got to work alongside everyone else. Spain is one of the most pragmatic countries I have ever encountered. The emergency powers were rescinded within hours but it is probably a hint at the geographical source of the problem. 🤫
Disclaimer: half my family is Spanish. 😂
Already, everyone I know is remarking on how much they learned about keeping cash in the house along with radios, etc.,
Outside of Spain, it always fascinates me how there's often a little undercurrent of racism whenever there's a drama - as if those southern Europeans (yes, Italy cops it too) are not 'quite up to scratch'. Oh boy.... I hate to say it but returning to the UK after years of living and working in Spain was like coming to what used to be referred to as a 'third world country'.
"Clearly it won’t have helped since it has no inherent inertia, (a technical term for traditional generators having large flywheels that run at nearly a constant frequency)."
I love this! A lovely graphic way to explain, I may have to ask you for an interview one day. 🙏🏻😊
Now you know why your parish council keeps sending round flyers telling you to keep cash, tins of soup and a radio etc., 😁
I just want to add (but it's too late to edit), that apart from the very patient, personal explanations from the Spanish engineer yesterday, information was kept updated throughout the day, press calls were regular and open to questions, and everything was really transparent.
There's a real lesson to be learned by all of Europe in how this was handled - transparency and accessibility was key and they did that really well.
It kept the public calm, they were comfortable saying 'we don't know yet' or 'we thought this but now we know we were wrong'. And it worked - a big drama was defused by a 'no drama' approach.
@lucia is this regular update available on line still? My Spanish might not be good enough but it would be interesting to try!
2kW + Growatt & 4kW +Sunnyboy PV on south-facing roof Solar thermal. 9.5kWh Givenergy battery with AC3. MVHR. Vaillant 7kW ASHP (very pleased with it) open system operating on WC
@lucia is this regular update available on line still? My Spanish might not be good enough but it would be interesting to try!
No, sorry it's not. It was a press call*. Plus I think I already mentioned I'm on a project looking at the European grid. Thus I'm in touch with a few of the system operators and some experts so not all my info was sourced in the press call.
*Which was then creatively spun by certain well-known anti-decarbonisation journalists who I'm far too polite to name but are the source of the famous energy trader put down: "You've been Bloomberged". 🫢😂
The spin is off the clock, what with the instant experts, the anti-decarbonisation brigade and Mr I'm-sponsored-by-Saudi-Oil Blair and his idiotic Carbon Capture nonsense on FOUR front pages this morning [🤦🏻♀️] it's quite ridiculous.
I was given some information by Spanish engineers last night that flies in the face of some of the 'inertia' theories. But as I'm way too busy today to start phoning Red Eléctrica to check it out - I'll leave it at that. If I get anything confirmed I'll post it but I skived off work too much already. 🤫
We need Red Eléctrica to publish their report. All the European grid leaders 'met' yesterday briefly and a few have made comments but mostly to grab bragging opportunities along the 'it couldn't happen here' line or to plug whatever is their latest lobby subject.
Lol... thanks to @judith I cracked and gave the Spanish wires a quick look..... Oof, let's just say we're at the finger pointing stage of analysis with direction of fingers determined by political outlook. 🤦🏻♀️
Lots of calls for Beatriz Corredor, RE's president, to resign. She in turn has gone public to say, 'it was not caused by renewables' (which interestingly, in a far more technical form, concurs with what the Spanish engineer told me last night.) She also said they have a 'good idea' of the cause but there's thousands of data points to analyse before they form any conclusions.
There is now a Commission of Enquiry whose remit, interestingly, is both RE and 'private operators'. Hmmmm....
Whilst we're still awaiting any explanations from official sources @judith may I point out that the symptoms indicate that the Spanish engineers did take immediate action on the original failure, and called on generation assets which were properly assigned to be on stand-by.
There was then a secondary failure, causing a greater loss of electricity supply.
We don't yet know if that second failure was on the generation sources that they brought on-line from stand-by.
As I posted above, that's the situation which NG ESO faced in August 2019. They called on two entirely separate stand-by sources, each of which failed for different reasons †
The key issue in our case was that ESO also implemented extensive load shedding across a very wide area... ... far beyond the areas in East England where the faults occurred. ‡ That's what stopped the frequency continuing to fall.
† The supplies failed from both Hornsea offshore wind farm (a loss of 737MW) and Little Barford gas-powered generators in Bedfordshire (244MW loss from plant-1, followed by 187MW from plant-2).
‡ Load shedding is properly called Low Frequency Demand Disconnection (LFDD). All DNOs have designated areas to which supplies will be cut by opening the breakers. In August 2019, more than 1.1bn properties were disconnected by LFDD, reducing demand by almost 1GW. LFDD is a fully automated process, requiring no command to be issued by ESO.
This post was modified 3 weeks ago 2 times by Transparent
This is from data provided by a serious researcher with monitoring kit implanted across the EU grid it's not opinion. I didn't get it from Red Eléctrica so we still have to wait for the official details, and,'nothing is ruled out, yet'. (below paraphrased by me):
At 12.33 the there's 2 drops in frequency, associated with the two losses, and then a rapid rise and fall in frequency outside Spain as the FR-SP interconnectors began to interrupt and the full event unfolds from 12h33 CEST. The main events lasted less than twenty seconds.
It was the France/Spain interconnector tripping that triggered the cascade.
What is absolutely extraordinary (utterly thrilling for my project 😁) is today I was told that frequency disturbances were observed as far away as eastern Europe.
The investigation committee met for the 1st time today and data has been demanded from all parties in one second increments. As one of my expert contacts said, there's absolutely extraordinary amounts of data to be analysed and this will be poured over avidly for years to come and will probably fuel numerous PhDs.
Everyone 'in grids' is saying that the speed and efficiency of Spain's Black Start recovery in a system with high amounts of renewables was absolutely superb.
[Meanwhile, I was eaten for breakfast by Spanish colleagues for praising the communications - they thought it was crap.]
Lots of horrible stories emerging about people stuck in lifts or trains but also really interesting ones about community energy groups and Almeria University remaining completely unaffected because they have their own renewable energy resources and 'islanding capabilities'.
The supplies failed from both Hornsea offshore wind farm (a loss of 737MW) and Little Barford gas-powered generators in Bedfordshire (244MW loss from plant-1, followed by 187MW from plant-2).
That's interesting why did the wind farm supplies fail? And then one after the other... Yikes!
European national system operators are quite extraordinary and the learning and systems perfecting across the European grid is really fascinating.
And here's the textual description of what happened to the supply from Hornsea:
I probably need to explain the term de-loading from para.2 above
Unlike a solar panel, a wind-turbine needs to deliver its output into a Load. The speed of rotation (angular momentum) is inversely proportional to the resistance (& inductance) of the load.
Increase the resistance, and the speed decreases.
The controller firmware in each turbine optimises the speed of rotation so that the blade tip travels slightly slower than horizontal wind-speed. If the tip/speed ratio were to increase, then that portion of the blade would no longer capture energy from the wind.
If you were to open the circuit breaker (completely removing the load), the turbine would turn ever faster because there is no load acting as a brake. Left unchecked, the turbine generator would overheat and catch fire.
Not only does each turbine have its own load controller, but there's a shore-based controller which delivers output to the grid from the entire wind-farm. This is a dynamic operation, functioning in milliseconds.
It is the shore-based equipment which senses anomalies in the national grid, and acts to prevent the wind-farm delivering power which falls outside the statutory envelope.
When the onshore equipment sensed the sudden voltage drop on 9th August 2019, it responded (correctly) by reducing the amount of 'load' which could be 'seen' by the turbines themselves. That's the 'de-loading' mentioned in the ESO Report.
The turbines slowed down. Within 20mS (milliseconds) the output power being dispatched to the grid fell from almost 800MW to 62MW.
Doubling of annual allowance for distribution network spending. Sounds a lot to me.
"Much of the final framework was shaped by a report by the National Infrastructure Commission (NIC), which was completed in February 2025. The NIC’s report stated that nati Doi ddonally, between £37 billion and £50 billion of investment into the electricity distribution network could be needed to support additional demand and generation between now and 2050, a sum that represents at least a doubling of current annual allowances for distribution network spending.
Ofgem noted that the NIC’s broader recommendations have already been incorporated into their ED3 framework policies."
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