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From my submission to the DESNZ non-profit factors for CFD enquiry into back door subsidies they are considering offering:

<i>Ministers, politicians, journalists and civil servants seem to think that wind costs £37.50/MWh (forgetting that that is a) a 2012 money price, and b) merely the strike price for a not very valuable put option currently at the level of about £50/MWh). It might shock them to realise that the average CFD is costing consumers £170-175/MWh – a substantial premium to current market prices, with a REGO top-up now worth £9/MWh. </i>

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I just saw your post on twitter. Essentially, the question is how efficient wind power is. To be efficient, the energy used to construct wind power stations, including construction, must be much less than the energy produced by these structures. It would be fantastic if you could find data on it. I simply don't have time to delve into it.

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The issue is not how efficient wind turbines are at generating power, it is how efficient they are at delivering power on the grid. Wind power is anything but steady. It will often generate low amounts of power for days or even longer than a week. When the wind is blowing strongly, wind turbines can overload the grid. How do you incorporate such an acutely variable source of power into a grid? That's the question.

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I never thought they would be able to cope with the amount of wind we currently have. ISTR reading an article 15 years ago about why the UK should never have more than 5GW wind on the grid (by Hugh Sharman I think). The thing is they have coped. The question is “but at what cost?” And what is it going to cost if they carry on expanding wind? I used to support wind, but I don’t think I want any more. I do like the idea of small nukes though.

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author

I think nukes large and small are the way forward. High density, high EROEI and reliable. We cannot continue to paper over the cracks emerging with too much wind.

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Sorry it seems it was 10GW - https://www.icevirtuallibrary.com/doi/abs/10.1680/cien.2005.158.4.161 I knew Hugh Sharman’s mum!

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Both concepts are important: EROEI and intermittency.

If it were up to me, I wouldn't even bother trying to incorporate wind into the grid.

https://davidturver.substack.com/p/nuclear-power-everywhere-all-at-once

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I agree, wind is poorly suited for grid support. It is quite good at intermittent tasks in many areas. The only reason it looks at all economically feasible is that the costs of compensation for the variability are shoved off onto the compensating generators. Wind is pretty much Power-to-X, which of course cuts the final efficiency massively.

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author

I did that already. On this post on the sustainability of renewables where I cover Energy Returned On Energy Invested (EROEI). Once you consider the buffering required to cover wind lulls using batteries or hydrogen, wind fares badly on EROEI.

https://davidturver.substack.com/p/wind-solar-renewables-not-sustainable-not-green

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Thanks. I just briefly looked at it and will read more in details. It is seems what I was thinking since it's logical but of course better when having real data. I live in Germany which now relies on green energy. I made be sent to jail if share it ....

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Since you live in Germany, you may be interested in viewing the acutely variable nature of wind there. https://www.agora-energiewende.de/service/agorameter/chart/power_generation/23.05.2022/23.05.2023/today/

Adding more wind doesn't cure the acute variability. It exaggerates it. That is why Germany keeps looking at hydrogen. Hydrogen may be inefficient, but without Power-to-X, wind can be no solution at all. With Power-to-X, wind is merely a very expensive solution.

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Here's the flip side of the coin 5 months later.

https://i0.wp.com/wattsupwiththat.com/wp-content/uploads/2023/05/SA-Gen-4-May-23-1685033490.8262.png

Little wind, not much solar, no curtailment, but heavy dependence on gas and imports (effectively coal based) plus use of costly diesel.

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Yes, it is a very expensive solution. It is much cheaper to start by over-investing in capacity and curtailing surpluses. But that too starts getting expensive. Try looking at the relative contribution of curtailment and storage on a typical day in South Australia.

https://i0.wp.com/wattsupwiththat.com/wp-content/uploads/2023/05/SA-Gen-5-Jan-23-1684966578.2893.png

The total generation potential is given by the area of the solid bars, and includes the blue amount of curtailment at the top of the heap. That curtailment was applied to wind and utility solar, which is fairly evident from the data of what they did produce. Some of the surplus was exported (shown negative below the line, and also as difference between local demand on the grid and total generation from the grid. A large chunk of demand was met by rooftop solar. The red line running through it shows that if the commercial generators were not curtailed, about half the rooftop solar would have had to be curtailed. The orange line above it removes the export volume to give total local demand met by grid and rooftop. The very puny contribution of the batteries to solving the problems is also evident: more detailed examination shows they were really mainly being used for grid stabilisation rather than serious storage.

With grid prices running negative for so much of the day it is hardly an incentive to invest in more renewables capacity. Backup generation from gas and diesel barely figures on this day, so must aim for high profits when it is run to cover its fixed costs. The crunch for rooftop solar will eventually be painful as the cost of the subsidies and all the necessary grid curtailment and extra transmission capacity and interconnector links it causes becomes unsustainable. Even 4 hour duration storage to absorb the solar peak and replay it in the evening struggles to be economic. Anything longer duration to cover for multiple days of Dunkelflaute stands no chance - and a seasonal store less still. Remember that hydrogen uses three times as much storage space as methane for the same amount of energy. And you are looking at a very low efficiency round trip with low utilisation rates on your plant that reduce its operational efficiency too.

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Thanks I will take a look.

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Is there a good explanation anywhere of how these CFDs are supposed to work? I’m having trouble understanding the mechanism and where the data on it all is published. If it is. How does this “market” actually work? Something not right when wind generators get paid gas prices... unless that’s what those refunds were? The whole thing seems way too complex. So you can’t see what’s going on.

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author

There's a primer here: https://www.lowcarboncontracts.uk/index.php/contracts-for-difference

Essentially the developers enter into a contract (CfD) where their revenue per MWh is the strike price for the CfD (index-linked so it goes up every year). If the market price of electricity they generate is lower than the strike price they receive a top-up subsidy to the strike price. If the market price is higher, then they have to pay back the difference. For a short while in 2021 & 2022 market prices were higher than the strike prices, so they were paying money back. Now gas prices have fallen, market prices for electricity have fallen too and they're back to receiving subsidies. Subsidies likely to increase because the strike prices have gone up with inflation.

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(Why) is that better than having a fixed-price contract, index linked if you like?

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Because consumers would never have agreed to pay the highly inflated prices necessary. Instead, wind farms sell into the market at market prices, and the compensation they need to secure their subsidised prices is totted up across all wind farms, and then recharged to retailers in proportion to the customer demand they serviced. In fact retailers have to put up funds in advance normally or are delayed in receiving compensation when market prices are high, and trueing up the position is always in arrears. The levy is compulsory.

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author

I am not sure.

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I am guessing it is so that the benefits fall to the producers and generators rather than us consumers. Low-bid fixed contract prices should dilute high gas prices in a proper market shouldn’t they?

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May 23, 2023Liked by David Turver

The Govt should call time David but it won't, for two reasons; it means they were wrong to back this horse in the first place AND many of them have some vested interest in green power ( just look at Skidmore who recently undertook a review of Net Zero and concluded 'nothing to see here'). The nrs presented are compelling and something Net Zero Watch have also been exposing, but most of our Masters are numerically illiterate. Good work.

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