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A Quarter Of UK’s Electricity Could Be Wasted By 2030, Thanks To Intermittent Wind Farms

May 16, 2022

By Paul Homewood

From Current+



If the UK meets its expanded renewable and nuclear targets, the country will have an oversupply of electricity more than half of the time by 2030, creating significant opportunities for flexible demand.

In new research from LCP, the company looked at the generation targets outlined in the British Energy Security Strategy alongside expected levels of demand, and found that 53% of the hours in the year, the UK’s grid could have an oversupply of renewable and nuclear power. By comparison, in 2022 it is expected there will only be an oversupply in 6%.

The security strategy outlined a new target of up to 24GW of nuclear power by 2050, and up to 50GW of offshore wind by 2030. It additionally highlighted that solar could grow five-fold by 2035.

“The energy strategy received the headlines for ambitious and laudable energy generation targets but a closer look reveals the significant challenge of building a decarbonised future energy mix that delivers value for consumers and ensures security of supply,” said Chris Matson, partner at LCP.

“For more than half the time in 2030 the UK’s renewable and nuclear backed energy system will be producing more energy from renewables and nuclear than it uses. Simply wasting this generation would harm both consumers and investors so a whole system approach is essential to minimise the cost of delivering net zero.”

In 2030, there is now expected to be 72TWh of excess renewable and nuclear energy, or almost 25% of current demand. 50GW of demand-side flexibility from technologies like batteries, electrolysers and interconnectors will be needed to use all of this excess.

Accelerating the expansion of demand-side flexibility would reduce the cost of balancing the grid, mitigate falling revenues for renewable generators and help consumers recognise the wider benefits of renewable power, said LCP.

“The need for significant amounts of flexibility and back-up power shows the scale of investment needed in order to deliver the government’s ambition to achieve 95% decarbonisation of the power sector by 2030,” continued Matson.

“Without a concerted programme of policy and regulatory reform to unlock this investment on a range of supporting technologies, there is a risk that the strategy will fail to cut bills in the long-term, and actually puts them up.”

In addition to the need for demand-side flexibility assets, LCP estimated 45GW of extra back-up capacity will be needed to ensure energy security during periods of low renewable output.

This gap will likely be filled by bioenergy, hydrogen and carbon capture usage and storage enabled power plants. But, over 20GW of this capacity will be used in fewer than 5% of hours.

Focusing solely on investing in renewables therefore comes with risk, as investors will see their assets turned off for periods of time or not earning revenue, warned Rajiv Gogna, partner at LCP.

“However, a diversified approach that looks for more ‘value-add’ and opportunistic approaches to infrastructure investment can balance this risk by exploring less well-established technologies such as batteries which would sit well against generation assets,” said Gogna. 

This is the key chart from the LCP analysis:





If that 72 TWh had to be paid to constrain, at say £100/MWh, it would cost consumers £7.2bn. Given CfD prices and current market prices, I suspect £100/MWh would probably be a massive understatement.

There is of course talk of using this surplus for storage, electrolysis and export.:

‘”to keep balancing and constraint costs down, and to mitigate falling revenues for renewable generators, over 50GW of new demand-side flexibility from energy storage, electrolysers and interconnectors will be needed.”

But as usual, they conflate GW with GWh. It seems likely that large chunks of this surplus of 72 TWh will be concentrated during certain periods rather than spread evenly throughout the year. For instance, during summer when demand is low, and during windy spells of weather. Battery storage will be next to useless in this situation, because it typically can only store enough electricity to supply for an hour or two, rather than for weeks at a time which will be needed.

Export via interconnectors also seems highly optimistic, since the rest of Europe will probably also be in surplus. At best, we would have to sell at a huge loss.

As for electrolysis, the government’s plan is for only 5GW of capacity by 2030. And as the above chart indicates, the process would be horribly inefficient, given that it would not be working for large parts of the year. In any event, it is one thing constructing 5GW of electrolysing capacity; but it is quite another being able to store all of that hydrogen during the summer, for use in winter.

Which all brings us back to paying for the surplus to be constrained off. With 50GW of offshore wind, we would expect annual output of 175 TWh. A surplus of 72 TWh therefore represents 41% of that output. Looked at another way, this would mean the cost of wind power would be 70% higher, if the surplus is wasted, compared to the output all being sold as it is now. This totally transforms the economics of wind power, and the problem will get much worse beyond 2030 as more offshore wind is added. (And we have not even included the cost of standby capacity yet!)

I have deliberately allocated this surplus to offshore wind, because this is exactly the root of the problem lies. In a normal world, we would still build nuclear power for baseload, whilst solar power remains insignificant in the overall view of things.

But in a normal world, we would not be subsidising offshore wind farms.

  1. John Hultquist permalink
    May 16, 2022 3:07 pm

    Someone should spend a few pounds developing activities that thrive on intermittent electrons.
    Or a way to deprogram members of the Climate Cult.
    Or drop the “CO2 is bad” axiom and adopt an axiom that CO2 is both necessary and good.

    • Citizen Clive permalink
      May 16, 2022 5:38 pm

      Consider a box of 10,000 air molecules. 3 of them were co2 molecules. Industrialisation has added a 4th. How can one extra molecule in 10,000 cause global warming? I’m interested in science. And especially thermodynamics. When someone tells me one extra co2 molecule in 10,000 air molecules can cause global warming- that’s amazing! – I want to know how that works.

  2. May 16, 2022 3:28 pm

    Utter madness

  3. NeilC permalink
    May 16, 2022 3:30 pm

    “But in a normal world, we would not be subsidising offshore wind farms.”

    And onshore wind farms and solar farms, All of which are a desecration of the natural environment.

  4. Gamecock permalink
    May 16, 2022 3:36 pm

    I find this hilarious.

    “We are going to have so much electricity, we won’t know what to do with it!”

    “Oh, my, what are we going to do with the excess?”

    . . . when people will be dying from LACK of electricity. Excess will NOT be your problem.

    ‘Accelerating the expansion of demand-side flexibility would reduce the cost of balancing the grid, mitigate falling revenues for renewable generators’

    ‘Demand-side flexibility’ doesn’t mean what he thinks it means. And batteries and electrolysers are not customers. They aren’t ‘demand.’

    ‘help consumers recognise the wider benefits of renewable power’

    Wut? Consumers aren’t interested in ‘wider benefits.’

    And, as I have said before, when you have a power supply that has extremely low variable cost, such as wind generation, what you are ‘wasting’ is of very little monetary value. Zero incremental cost to produce, and nobody wants it. Wasting what is free isn’t an issue.

    • dodgy geezer permalink
      May 16, 2022 4:58 pm

      No. The issue is not having power when you need it….

    • It doesn't add up... permalink
      May 17, 2022 10:29 am

      But if 50% of the output has zero value then the other 50% must get twice the price to pay for itself. In fact, shortage pricing looks even worse. Any time there is a surplus, value drops to zero, so all MWh generated have zero value, including the ones that get used. That means that all revenue earning has to come from the hours of shortage, when the volume of wind generation is much lower.

  5. GeoffB permalink
    May 16, 2022 3:58 pm

    Will constraint payments to wind farm operators still be paid? Surely just stop the constraint payments and let the wind farm operators work out what to do with the surplus, it is up to them to finance the batteries, electrolysers, gravity storage (pumped water) etc. In fact remove all subsidies for green projects.

    • May 16, 2022 6:38 pm

      In some cases a quarter or more of electricity is already being wasted…

      Constraint Payments to Wind Power in 2020 and 2021
      17 February 2022

      Large volumes of wind energy are being discarded in Scotland in order to preserve grid stability, with a fleet average of over 13% of generation constrained off in the years 2015 to 2021, inclusive, with a high of 19% of generation in 2020. Some wind farms have been discarding between 20% and 50% of their output, while being rewarded with generous constraint payments from the electricity consumer for doing so.

      • It doesn't add up... permalink
        May 17, 2022 10:34 am

        A lot of the Scottish situation has been the result of insufficient capacity to transmit power to England. Things will get really difficult for grid stability when they lose their nuclear stations to closure.

  6. Cheshire Red permalink
    May 16, 2022 4:04 pm

    Our government has one objective; anything, absolutely anything but onshore gas.

  7. ThinkingScientist permalink
    May 16, 2022 4:12 pm

    Having an excess when you don’t need it is what is often referred to as a glut.

    So if we have a glut of apples, the price falls and they are unsold, uneaten and rot.

    Of course with wind there is the other side: the shortfall. When we have a shortfall either the price will go through the roof or the lights will go out. Or both.

    Do any of these people understand supply and demand?
    Do any of them understand that they are building new infrastructure to replace existing infrastructure, but the new infrastructure is an inferior technology to the existing? Less efficient, more expensive, less reliable.

    The lunatics are in charge of the asylum.

    • May 16, 2022 4:30 pm

      “Do any of these people understand supply and demand?
      Do any of them understand that they are building new infrastructure to replace existing infrastructure, but the new infrastructure is an inferior technology to the existing? Less efficient, more expensive, less reliable.”

      No! All they know is that they are saving the planet from …???? Additionally, the can not admit that this new infrastructure adds costs to the required old infrastructure which must remain in place. Not matter the new intermittency solutions.

      Amazingly, even on economics blogs these issues are not discussed.

  8. Jack Broughton permalink
    May 16, 2022 4:19 pm

    I looked in the original document and there is no y-axis values in that either, so, for how many hours per year are we “balance”. I also looked at the reference publication “British Energy Security Strategy”: this sad document is good for a laugh only: in no way does it address energy strategy to cover windless days (apart from fantasy junk), nor our dependence on imported fuels. In fact it is a sort of wish-list for the green woke brigade.

    • It doesn't add up... permalink
      May 17, 2022 10:39 am

      Consider the area under the curve to be 100% of time, so the area highlighted in orange is 5% of the time. It’s effectively a probability distribution of the sizes of surpluses and deficits.

  9. dodgy geezer permalink
    May 16, 2022 4:27 pm

    IF we gave everyone batteries, and paid them to take energy when it was over-produced, then we might have an operational energy system….

  10. Jack Broughton permalink
    May 16, 2022 4:31 pm

    Returning to the axis-challenged chart, if we assume that for 50% of the year we will need storage, the storage required is approximately 25 GW x 4000 hours = 100 TWh: we currently have Dinorwig and Cruachan which total below 10 GWh. So the storage needs to increase by 10,000 times – not bad eh! We used to store 55,000 TWh gas under the north sea, but that is now much reduced due to idiotic energy policy makers.

    • Joe Public permalink
      May 16, 2022 7:45 pm

      Hi Jack

      ” … we currently have Dinorwig and Cruachan which total below 10 GWh.”

      The late Prof Sir David MacKay’s excellent freebie “Sustainable Energy — without the hot air” informs that the energy stored in our 4x pumped-hydro storage facilities is 26.7GWh:

      Ffestiniog 1.3 GWh
      Cruachan 10 GWh
      Foyers 6.3 GWh
      Dinorwig 9.1 GWh

      Page 191 here:

      Click to access cft.pdf

      In Oct 2020 – COIRE GLAS consent was received for its 30GWh facility; construction was expected to take 5-6 years.

      • Jack Broughton permalink
        May 16, 2022 9:59 pm

        Thanks for this, Joe, I have been to Cruachan and Dinorwig: two more to visit!
        Still a fair imbalance between excess capacity and storage.

    • It doesn't add up... permalink
      May 17, 2022 10:56 am

      Actual storage calculations need to be done hour by hour or better, because you can swing between surplus and deficit very quickly as a weather front goes through, and because of the swings in demand. If we swung from 10GW surplus to 10GW deficit every hour you would need a 10GWh store if it was 100% efficient. If we had a 10GW surplus for 6 months continously and a 10GW deficit for the next six months the store would need to be 4,380 times as big. The real world is in between those extremes.

      You need more wind input if the storage round trip is inefficient. I did hour by hour calculations for 2021, taking actual demand and scaling up wind output as necessary, summarised in this chart. If you use inefficient hydrogen you must store more energy.

  11. George Herraghty permalink
    May 16, 2022 4:55 pm

    And then the wind stopped.

  12. It doesn't add up... permalink
    May 16, 2022 4:56 pm

    The LCP chart is actually effectively a probability distribution for the size of surpluses and deficits. The thing is there is no way you would actually invest to store the 50GW of maximum surplus, because that happens infrequently You might perhaps justify surpluses of up to 20GW, but even that would be a stretch. So you are going to end up curtailing a lot even if you do make some use of storage. Still, at least they are beginning to think about it.

  13. markl permalink
    May 16, 2022 6:04 pm

    The more renewables added the more reliability declines. Pretty soon we’ll be at the point where we’re told it’s our fault for using electricity at the wrong times because there’s more than enough available. Wanna bet?

  14. Dave Ward permalink
    May 16, 2022 6:51 pm

    Am I missing something? Why would you “waste” nuclear energy – surely you keep those power stations running flat out, and shut down (without compensation) the wind farms. Minimum demand is rarely less than 25GW now, so when everybody is driving EV’s and attempting to heat their homes with heat pumps, it’s going to be considerably more…

    • Gamecock permalink
      May 16, 2022 7:22 pm

      And there is no reason to believe nuclear energy will actually reach ‘up to 24GW of nuclear power by 2050.’

      RR SMR might approved by then.

      I also wonder about their claims for 2030. They keep saying ‘and nuclear’ for 2030, while the big growth they talk about is for 2050.

    • Harry Passfield permalink
      May 16, 2022 7:48 pm

      Although one may be able to curtail wind/solar and use nuclear as a banker, one cannot ramp up wind/solar on a windless night should nuclear baseload not be sufficient. We shall always need gas and/or coal.

      • Dave Ward permalink
        May 16, 2022 9:08 pm

        “One cannot ramp up wind/solar on a windless night should nuclear baseload not be sufficient”

        Absolutely – but my point is that’s it dead easy to curtail wind & solar, rather than nuclear, in the unlikely event that demand is really low. And since neither of them can be relied on to meet actual demand at all times, THEY should be the ones which are curtailed, not reliable & predictable generation!

        We shall always need gas and/or coal”

        I’m sure everybody on here knows that, but it seems politicians (and the so called “experts” who advise them) don’t…

  15. Peter permalink
    May 16, 2022 7:08 pm

    Electricity created has to be used. Supply and demand must always be in balance. Germany made the same mistake. They thought that the answer to intermittency was more wind turbines. Now, when they have too much electricity, they have huge problems trying to sell it, so they have negative prices. They pay other countries to take it. They end up screwing up the market and the grid. When the wind is not blowing, they still need Russian gas.

  16. John Brown permalink
    May 16, 2022 10:04 pm

    The 24GW of nuclear by 2050 is 8 reactors at the rate of 1 per year. So this means from 2043 to 2050 and hence the only nuclear planned for the decarbonisation date of 2035 is Hinkley Point C (3.2GW) if it is delivered by then.

  17. Ray Sanders permalink
    May 16, 2022 11:31 pm

    If anyone is interested, the “carbon intensity” of the UK grid is rapidly increasing. We have transformed into a net exporter of electricity to Europe (gas also). The change from being a net importer of about 15% to a net exporter means that a bigger proportion of our generation counts to our figures as the exporter. According to this (rather dubious) website the last 28 days are 267g CO2 per kWh which is back at 2017 levels.
    Just shows how easily the books have been cooked.

  18. James Broadhurst permalink
    May 17, 2022 5:11 pm

    LCP’s members are paid £0.5million each to produce this nonsense and the llp has hundreds of members. What we don’t know is who is paying them because that is a serious amount of money.

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