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Govt’s Wind Strategy Ignores Intermittency

April 22, 2022

By Paul Homewood

I have already looked at this, but let’s focus more closely on wind power:


Central to the strategy is an ambition to build offshore wind from 12GW to 50GW, along with an increase in solar power. Indeed these were really the only concrete promises; most of the rest of the strategy is little more than flimflam.



Technically, if you assume average outputs throughout the year, it should be possible to get to 95% of low carbon electricity by 2030, or close to it, with suitable assumptions about nuclear capacity:



The total annual generation above comes to 332 TWh, close to likely full demand.

But, of course, intermittent renewables don’t operate at the same rate all year round. I have analysed the daily offshore wind generation data available from the CfD database for last summer. The CfD database covers about 40% of the UK’s total offshore capacity, so should give a fairly accurate picture.



Over the three month period, daily loading ranged from 1% to 68%.

Demand in summer averages 32 GW. Let us assume that we have storage to manage intra-day fluctuations in supply and demand (a very big if!). On a typical summer’s day, with 50 GW of offshore wind, plus extra onshore, we could easily find ourselves with 15GW of surplus power – this will have to be either constrained, or sufficient storage set up to handle it. Even the planned 5GW of electrolyser capacity will only absorb part. (BTW – this 5GW will remain unused most of the year, making it wholly unviable economically).

At the other extreme, when wind power is near zero, we will only have about 13GW of low carbon capacity available. This will presumably mean firing up 20GW or more of gas-fired capacity, unless we plan relying on inter-connectors.

The power shortage on a windless winter day will naturally be far more critical. We can expect average daily demand to peak at at least 60GW, given extra demand for EVs and heating. With average wind speeds, the power mix would look like this, with low carbon sources making up about 35GW, leaving 25GW needed from somewhere else:


However, on the sort of windless days which are common in winter, when offshore wind is generating at less than 5% of capacity, we end up needing 48 GW from “somewhere else”:


We currently only have 30GW at most of gas power capacity, and much of this is due to close in the next few years. Yet there was no mention at all in the government’s new energy strategy of when or how any of this was going to be built.

  1. April 22, 2022 3:54 pm

    European Weather-Dependent generation 2021 analysed and visualised

    2021 European Wind Drought and “Renewable” generation

    • April 22, 2022 5:52 pm

      Thanks Ed – that is a useful data presentation.

  2. GeoffB permalink
    April 22, 2022 4:00 pm

    When the wind stops, instead of power cuts, electricity will be rationed by price, if you are rich, charge your car and run your heat pump, the poor freeze. Its DSR in a National Grid document, I think it stands for DownSide Reduction. Maybe EV batteries are used, who knows? It is just not going to work.

  3. April 22, 2022 4:47 pm

    It is impossible to get the message through to the government and its ministers as they do not understand the issues, and they are surrounded by green civil servants who create these mad policies. Since Prof Sr David MacKay’s untimely death, there has not been a scientific adviser who understands the issues.

    • dave permalink
      April 23, 2022 9:22 am

      But – seriously – what is there to understand? Perhaps the Arts graduates who seem to rule everything nowadays confuse Science with Magic? Do they genuinely imagine that ‘anything is possible,’ if you shut your eyes and wish hard enough?

      I am also reminded of Professor Parkinson and his distinction between the reborn Cavalier and Roundhead traditions in Britain since 1800. The latter feel, in their bones, that anything worthwhile has to be crafted and nurtured, and is always liable to crumbling into dust The former think that this is a lie by killjoys. And even if it is true they do not care. They simply steal from our table – what they can, while they can. After all, in their smug self estimation, ‘they are worth it!’

      • Gerry, England permalink
        April 23, 2022 10:27 am

        Yes, pretty much. The moron in charge of transportation at the City of London believes ‘the market will find a way’. this was in response to complaints from the brewery logistics trade that they were finding it near impossible to deliver to pubs in the City due to the stupid restrictions introduced for covid – to provide space for people who never turned up to work anyway – and eagerly made permanent for his vision of a City of only pedestrians and cyclists. And yes, there was even talk of how cargo bicycles could deliver casks and kegs to pubs. The City was full of these types. Luckily at the other councils I worked at the people were quite normal.

  4. April 22, 2022 5:00 pm

    Over the month of July 2021, our entire fleet of wind turbines generated at less than 10% Capacity Factor.

  5. April 22, 2022 6:02 pm

    California is the canary in the crazy renewables ‘coal mine’. Already a fairly dire picture.

    California has the distinction of simultaneously having the nation’s worst air quality, among the highest gasoline and electric power prices, the most electricity generated by renewable sources, and the least reliable electric power grid.

    The latter three points are a direct result of California’s green energy mandates.

    • Graeme No.3 permalink
      April 22, 2022 10:49 pm

      And for some reason a lot of those born there are leaving or have left for other States.

      • Gerry, England permalink
        April 23, 2022 10:28 am

        The other states should build fences to stop these idiots coming in and polluting their states.

  6. Gordon Hughes permalink
    April 22, 2022 6:04 pm

    Paul: The prospective situation in 2030 is far worse than these figures suggest.

    1. There may be a nominal 30 GW of CCGT capacity but in reality the day-ahead market goes into meltdown if required to deliver much more than 18 GW of CCGT output. Most of the remaining 12 GW is effectively mothballed.

    2. Midday on a sunny windy day in 2030 (they happen!). Not only do you have 50 GW of offshore wind but also at least 30 GW of solar + 15-20 GW of onshore wind + nuclear + biomass. Demand of perhaps 35-40 GW – so excess potential generation of 60+ GW. No-one has any idea how to manage that. The cost of constraint payments will rapidly break the balancing cost system since the total cost will run into £ tens of millions per hour. Hence, producers will have to be switched off without compensation. But that will rapidly bankrupt both solar and wind generators.
    The simple lesson is: beware of getting what you wish for. It isn’t just periods of low generation that matter but also what to do when there is too much generation.

    • April 22, 2022 9:48 pm

      The problem of excess intermittent and uncontrollable generation has been pointed out repeatedly to the government and its advisers. It falls on deaf ears (or dead brains). How do we get the message across before the first catastrophic failure occurs?

      • Gerry, England permalink
        April 23, 2022 10:30 am

        You can’t. Morons only learn from experience, which sadly means that those of us with intelligence have to suffer too.

    • It doesn't add up... permalink
      April 23, 2022 12:13 pm

      Question for Gordon.

      What data on curtailment is available from where? It would be a start to have settlement period data at the level of aggregated onshore and offshore and solar totals with a good history. Even better to extend that to individual wind and solar farms.

      • Nicholas Lewis permalink
        April 23, 2022 7:04 pm

        You can get constraint costs from the daily balancing report off NG ESO site as to how you work out which sites have been told to constrain im not sure. Anyhow i looked up the largest onshore windfarm South Clyde at 522MW and their 2021 annual report stated that they were instructed to constrain 255GWh of production out of a total 1.19TWh of annual production or 17%. Its bad enough these have intermittency but when they also have to constrain them and be paid to do so its madness. Then even if they had been able to export all the power they would have achieved 31% utilisation all for £800m.

        What more obscene is that they have a profit margin of nearly 30% and that’s at prices which were substantially lower!

    • It doesn't add up... permalink
      April 23, 2022 2:48 pm

      Here’s what quadrupled offshore wind generation would have implied last December:

      Lots and lots of curtailment, and still the need to keep the CCGT capacity to fill in when the wind died.

  7. Malcolm permalink
    April 22, 2022 6:41 pm

    Great analysis Paul – it shows how badly we need a real energy policy, formulated by adults.

  8. tomo permalink
    April 22, 2022 7:20 pm

    of course they ignore intermittency – if I had £1 for every time I had to explain it to somebody who’d drunk the 100% Renewbabble Kool Aid – I could likely afford an EV!

  9. tomo permalink
    April 22, 2022 7:30 pm


    In la-la land

  10. Nicholas Lewis permalink
    April 22, 2022 7:58 pm

    NG is already shelling out a fortune on our behalf on balancing costs (well over 2B so far this FY as of Feb 22 update from NG) and whilst wind constraints costs will outturn much more favourable than previous financial year, in part that is due to lower wind output, this has already absorbed billions in network reinforcement.
    I don’t believe NG had developed a credible plan to get to previous target without adding in another 10GW so this is undeliverable. Even the lower target needs billions to be spent on more network reinforcements.
    Personally I believe we will see less than favourable outcome to the next CfD auction as there is increasing price pressure in the renewable supply chain so if in correct that will be another prop pulled from underneath the green fantasy. Then on top of that we have the entire Western world now jumping on the renewables band wagon so the ability to deliver all these projects is debatable.

    • It doesn't add up... permalink
      April 23, 2022 7:24 pm

      I think that the CFD auction is now no more than a charade. They have unrealistically low strike prices, and completely unrealistic assumptions behind that allocation methodology. Anyone who bids does so knowing that the CFD strike price is meaningless in terms of their future revenues, which will be on some other basis, probably wiht large dollops of subsidy for supplying the hydrogen industry as at least one element of it. Who is going to exercise a CFD that forces them to hand over £140/MWh when the market price is £200/MWh?

  11. Gamecock permalink
    April 22, 2022 8:05 pm

    ‘This will presumably mean firing up 20GW or more of gas-fired capacity, unless we plan relying on inter-connectors.’

    High penetration of wind into electricity market will mean there is no business case for gas-fired capacity. Bye bye backup! At some level of penetration, the business case for gas-fired will fall off a cliff. I.e., it will shut down suddenly when the time comes.

    Additionally, high penetration of wind also creates a big problem with frequency management. Really big problem. Sudden loss of rotating mass generation could leave you with NO ELECTRICITY. PERIOD. Even if the wind is blowing, because you won’t be able to control the frequency.

    You can’t imagine how much trouble you are going to be in. The government’s plan is NO ELECTRICITY. Someone in the government has to know this.

    • April 22, 2022 9:44 pm

      I doubt whether anyone in government knows or understands this. Certainly not Kwarteng or Johnson.

    • It doesn't add up... permalink
      April 23, 2022 7:33 pm

      The National Grid plan is to try to maintain at least 140GVA of inertia (or about 3 seconds at higher levels of demand), including via synthetic means, synchronous condensers, fast reaction batteries etc. They had a little practice run on the 18th April, when the whole 1.2GW of Sizewell B tripped out at about 16:25. At 15 second resolution we know the frequency fell at least to 49.651Hz, and may well have been lower still when examined on a second by second basis, possibly threatening the statutory minimum of 49.5Hz. Barely half an hour beforehand there had been a big ramp down of about 2.7GW of interconnector imports over about 10 minutes. If the events had coincided I suspect they might have been in blackout territory. They were also fortunate that there was a good chunk of CCGT providing inertia and reserve.

      • Nicholas Lewis permalink
        April 23, 2022 11:54 pm

        Don’t worry NG have Dynamic Containment, Dynamic Regulation and Dynamic Moderation to deal with that. Hugely expensive solutions on a just in case basis to replace the rotational inertial that came free with spinning machines.
        The idiots in power don’t seem to realise that the existential threat comes from blowing up our economy and the social unrest that it will bring not the risk of a few cm on sea level.

  12. J Flood permalink
    April 22, 2022 9:57 pm

    When he was Minister for Energy and Climate Change I told Matthew Hancock that he was playing Russian roulette with the Grid? The only change now is that there are two shells in the revolver.


    • Gerry, England permalink
      April 23, 2022 10:31 am

      Are you sure they aren’t playing it with an automatic?

  13. jimlemaistre permalink
    April 23, 2022 6:58 pm

    We argue and rant about ‘Efficiencies’ of wind turbines while ignoring the Elephant in the room. As much CO2 is released into the Environment during the production of these monstrous machines than they will ever save the environment during their productive life span. Not to mention the egregious ancillary pollution and radiation. Furthermore, almost all the key components are produced in China . . . like oil and gas from Russia . . . handing the keys of our future to an autocracy that may some day cut us off.

    Wind Turbines . . . are The Ultimate in ‘Embodied Environmental Costs’ and Environmental Destruction – Wind Turbines are described as ‘Clean & Green Technology and Renewable’. That is not even remotely true! The Environmental Protection Agency (EPA) Banned the Radioactive Waste from producing ‘Rare Earth Magnets’ contained in those Turbines. They were invented in the USA by General Dynamics, more than 35 years ago. Neo-Dymium Boron Magnets are also what Drive the Engines in those ‘Emissions free’ Electric Cars. Will Electric Cars End Pollution? NO! Sadly, Pollution is just moved out of site and out of mind to places off in the wilderness, unseen and un-spoken . . . Illegal to produce in ANY western country . . .
    We need to learn the Science first. Each one weighs about 1,688 tons (equivalent to 23 houses) and they contain 1,300 tons of concrete and 295 tons of steel for the masts (Concrete and Steel = 15% Global CO2). 3.5 tons of copper, 48 tons of iron, 24 tons of fiberglass Then there are the rare earth minerals . . . 800 lbs. of neodymium-boron per turbine, plus praseodymium, and dysprosium. The leaching into the environment from tailings ponds, the radiation released into the environment and the mining of these minerals are all ‘Embodied Costs’.

    Where are the calculations for all of these in The Environmental reports? Each blade weighs 81,000 pounds and will only last about 15 to 20 years, then, it must be replaced. Oh, we cannot recycle used blades yet either! That is why we see them lying on the ground at wind farms after they have been replaced. What about the coal burned and electricity used at all the production facilities processing these essential components and the CO2 generated during their production? Somehow is this ‘Green Magic’ without pollution, because it will be used to produce Green Energy? Not likely! It all gets brushed under the ‘Big Green Rug’ and seems irrelevant because ‘It’s for a Good Cause’ . . . Absolutely NOT! . . . All Pollution must be Eradicated . . . not just CO2

    One Wind Turbine contains 800 lbs. of Neo-Dymium Boron. More Radiation is released making these Rare-Earth Magnets in Mongolia, where 80% of Global demand is produced, than all the Nuclear Reactors in the USA combined, every day. As one environmentalist told the Daily Mail, “There is not one step of the rare earth mining process that is not disastrous for the environment.” Finally, it has been suggested that the energy input to build Wind Turbines, exceeds their energy output in their entire productive lifetime.
    Is that Green Energy? I think NOT !

    From . . .

  14. Old Nick. permalink
    April 29, 2022 10:37 am

    Well a very comprehensive analysis of the latest Gov pronouncements with wind and solar as significant elements addressed here.
    However I have a different take on the pronouncements.
    I think it is all a political statement (re wind and solar ) to ensure the green lobby are well on board with the Government, firstly for the up comming local elections and secondly for the general election soon. It is also drawing the teeth from the arguments expressed by the ant-global warming lobby by having the antis batter themselves time and again against an aparently imoveable, implacable, ignorant Gov.

    It is a bluff! How can you really think the MPs and civil servants are so ignorant of the issues.

    Keep your powder dry. Wait for a gov move to enact any of these so called ‘decisive’ policies. Then you know what to challenge.

    Prepare, prepare , prepare.

    Thanks for reading this rant duff spelling an all.

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