Correlated wind and incoherent energy policy

When the wind blows it is common for it to blow everywhere at once in Europe. When the wind doesn’t blow, it is common for it to be calm everywhere at once in Europe. No amount of electricity grid interconnection can solve this problem. This post casts another critical eye over UK Minister for Energy and Climate Change Ed Davey’s statements made to The Independent newspaper on 2nd January.

Figure 1 Stacked chart for actual wind generation from Germany, Spain and the UK for January 2013. Hourly data from (see end of post). The Green fantasy that it will always be windy somewhere and increasing grid connectivity could therefore move vast amounts of Green electricity around Europe is quaint. But real data shows it is also plain wrong.

In his interview with The Independent, Ed Davey said this:

…there was an urgent need to build a giant network of electricity interconnectors across Europe, allowing vast amounts of energy to be moved between countries, driving down prices.

In yesterday’s posting I made the point that there was not vast amounts of cheap energy just floating around Europe waiting to arrive on Britain’s grid, quite the contrary. And so one is left guessing what Ed Davey actually means and I presume he is referring to surpluses of wind power that are periodically produced during windy periods in Germany or elsewhere. And if this is the case it leaves me flabbergasted since actual wind generation data has existed for years that shows the Green fantasy of moving wind power from areas of surplus to areas of deficit quite simply will not work for much of the time.

Scrutiny of Figures 1 and 2 will show that there are periods of surplus in Germany and Spain and deficit in the UK, e.g. 10th Jan 2013. Every now and then, greater interconnection may help distribute surplus wind energy. But does it really make any engineering, economic or environmental sense to build a vastly expensive European super-grid that may only ever be useful every now and then?

Figure 2 Stacked chart for actual wind generation from Germany, Spain and the UK for June 2013. Hourly data from (see below). Note multiple episodes where the wind doesn’t blow anywhere in Europe matched my multiple episodes of wind everywhere at once. Also note the diurnal pattern prevalent for much of the month with troughs in supply during peak day time demand.

The UK urgently needs a sensible and competent energy policy and Energy Minister to match.


The data presented here was downloaded from the web site of Paul-Frederik Bach (right hand margin, international time series). Data compilations begin in 2006 and progress to include data for Denmark, Germany, Ireland, Great Britain, France, Spain and Belgium. Data include wind generation, exports, prices etc. Paul-Frederik has been assisted in this compilation by Hubert Flocard. Many thanks to Paul-Frederik and Hubert for providing this splendid and invaluable resource.

Other posts

LNG Heading East
UK North Sea Oil Production Decline
OECD oil production update July 2013
The changing face of UK electricity supply
Energiewende: Germany, UK, France and Spain
Brave Green World and the Cost of Electricity
A Primary Energy Tale of Two Continents

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51 Responses to Correlated wind and incoherent energy policy

  1. Hi Euan,

    Thanks for an interesting post and for the link to Paul-Frederick Bach’s site. I was interested to see how low the correlation between Spain and Germany was, 0.02. I do not know how strong the exchange is between those two countries.

    For the US Western Interconnect, the main wind areas so far are the Sierras in California and the Columbia River area in Oregon and Washington. Their correlation coefficient is 0.2. Wyoming, with its excellent wind resources, is also in the Western Interconnect region and could add a third source with relatively low correlation.


    • Euan Mearns says:

      Dave, as I understand things you need strong negative correlations between wind districts to make grid expansion worth while. Would you care to expand on correlations in western USA.

      In this post I just selected two recent months at random – one winter, one summer. I looked at correlations. R2 is always low and gradient sometimes positive, sometimes negative.


      • Hi Euan,

        I do not have the wind correlation coefficient numbers except for BPA/CA which was 0.2 as I mentioned. Negative correlation is certainly better than a small positive correlation, but a small positive correlation is better than a large positive correlation. My sense is that California will use up most of the good sites in the Sierras this decade, and will be adding wind from Wyoming in any event. In addition, California wind power drops by more than a factor of two in the winter. BPA generation is reasonable in the winter, and I believe that Wyoming generation actually would peak in the winter.


      • Roger Andrews says:

        Correlation coefficients for the first three quarters of 2013

    • Kit P says:

      “correlation coefficient ”
      Say what? I am waiting for Dave to explain the common sense of putting wind farms a thousand miles away so folks in California can feel less guilty about whatever they feel guilty about.
      Here are a links that shows lots of information about supply in the west.

      When it is hot in the west and power demand is the highest, there is no wind.

  2. clivebest says:


    Thanks for finding this valuable source of European wind data. Just reading off the graphs

    1. During the 2013/14 stormy winter Europe’s wind generation fleet averages out at about 20 GW.
    2. In June 2013 the average drops to about 12 GW.
    3. The peak power output is ~ 35 GW in winter and ~25 GW in summer
    4. The lowest power output is <3 GW in winter and <2 GW in summer.

    The peak demand of Germany, UK and Spain combined is time synchronized and is roughly 180GW. Power must be delivered in real time, to avoid power cuts.

    Therefore depending on the role of a dice wind either meets 20% of demand or less than 2% of demand.

    This obsession with renewables is simultaneously hiking up energy prices and destroying energy security across Europe. I wonder when or if we will come out of this fantasy world ?

    • Willem Post says:

      That will not happen until politicians get their hands out of the pockets of wind energy promoters. Voting them out of office is a good start.

    • Euan Mearns says:

      Clive, a few years ago I got via email wind data for Germany, Denmark and Ireland through Oil Drum contacts, been using that data in undergraduate and post graduate teaching in Aberdeen for a few years. I got to know Paul-Fredrerik through Hugh Sharman, a long standing e colleague. I hosted guest posts from both on The Oil Drum. Both are power industry engineers. Paul-Frederik was deeply involved in the development of the Scandinavian “energy pool” – I’m guessing he has his CV posted on his web site – everyone should check it out.

      All this is done on a voluntary basis! It is Paul-Frederik and Hubert you need to thank and send an email to David MacKay asking why vital energy data has to be acquired and published in this way. If DECC ever use it they should pay handsomely for it.

  3. Roger Andrews says:


    Going to think out loud here.

    You say: “When the wind doesn’t blow, it is common for it to be calm everywhere at once in Europe. No amount of electricity grid interconnection can solve this problem.”

    Well, actually it can, sort of. By interconnecting the wind farms with enough hydro plants the surges can be smoothed out simply by throttling back on the water flow through the turbines when the wind is blowing and by opening the sluices again when it isn’t, all other things being equal.

    The problem with this approach, however, is that it doesn’t generate any extra electricity. All it does is replace hydro with wind and retain more water above the dams than would have otherwise have been the case, which as residents of Brisbane know is not necessarily a good idea.

    Absent a miraculous breakthrough in battery or compressed air storage technology the only way of using wind power as independent baseload capacity is by storing it in new dedicated pumped hydro facilities. Which brings up the question of how much untapped pumped storage potential is there in Europe? According to a recent survey (link below) it could be as much as 80 TWh, but even this would fill EU27 electricity demand for only a little more than a week, and the way things are headed y’all would long since have frozen in the dark by the time Europe’s first new PH facility came on line anyway. So I guess it’s back to square one.

    • ghl says:

      Balance Hydro with Wind. A guarantee to save no CO2 emmissions. Zero !

      • Bernard Durand says:

        ghl, France’s power consumption is roughly 10 TWh a week. Suppose you have enough wind power capacity to produce this amount. To face just a week of wind lull (this occurs at least once a year in France), you therefore need a permanent 10 TWh storage capacity in dams , ie 100 times the existing one! For Europe as a whole, the story is very much the same, because the correlation between wind regimes at productive wind speeds is strong even at the european scale, as shown by Bach and Flocard. Conclusion: if you want to balance safely wind with hydro in Europe, you need dam storages in the order of a hundred times more than the existing storages. This is foolish. Furthermore, lulls of two or three weeks may happen !
        At the european scale the garanteed wind power capacity is in the order of 10 % of the nominal capacity. This means that to produce electricity this way in safe conditions and without storage or back-up power plants, you need to produce 10 times what is necessary, waste 90 % of the production, and also rebuild completely the existing grid.
        The power consumption of Europe being roughly 3000 TWh/year, you need to produce 30 000 TWh/year. The productivity of wind mill being on average 20 GWh/km2 per year on good sites, you need for that to cover with wind mills 1,5 million km2, ie roughly one third of Europe surface , which cannot be inhabited by human beings any longer.

        • Euan Mearns says:

          The Coire Glas pumped storage scheme – a massive but puny beast

          Bernard, I did a post on a proposed new pumped storage scheme in Scotland. Coire Glas is massive but still almost meaningless in the context of storing energy to power Britain for a week. Without storage, renewables need to be backed up with FF, mainly gas, that loses efficiency the more often it is switched on and off / ramped up and down. My concern is that we are on a course building out lots of renewables, inter connectors, storage – all costing the consumers money – and at the end of the day need to maintain virtually all our legacy generating assets that will soon be running at a loss. An effective doubling of generating infrastructure is an odd kind of Green solution.

          Your stats (above) are useful to have.

  4. Willem Post says:


    NOTE: Here is an article regarding the intermittency of wind energy in the UK, a windy country, which concludes, absent economically-viable, utility-scale energy storage (not yet invented), nearly all existing generators are needed to provide continuous electric service, as required by a modern society, no matter how many wind turbines are built in the UK.

    • clivebest says:

      This confirms other studies that up to 100% backup for wind is needed from conventional stations. But it is even worse than that because it would then be cheaper and save more CO2 emissions to run modern gas/coal plants flat out rather than use them intermittently to balance wind. The fuel efficiency drops fast once they are ramped up and down randomly. If wind reaches more than 20% of grid capacity then all carbon savings are lost. It is exactly the same effect as comparing fuel consumption of a car cruising at 60 mph with it driving through thick traffic and occasional traffic lights.

      Wind power is a waste of time unless the energy storage problem can be solved. If DECC had any sense they would pay for each MWh from wind according to grid demand. If wind power is delivered at peak times the producers would receive the full subsidy rate £60/Mwh, whereas if power is generated at 3am they would receive only £20/MWh. This would incentivise renewable suppliers to deploy energy storage solutions at the wind farm itself. It should not be the grid’s responsibility. As things stand wind farms are just a money making scam with no risk for the suppliers.

    • Biniput says:

      Yeah cite something from a well known anti-green website not at all about anti-green propaganda.

  5. Ted S. Lundy says:

    Ryan, The data contained within your messages support all conclusions you have reached! Ted

  6. Kit P says:

    “good sites in the Sierras this decade ”

    Sure, you bet that will happen just after Yosemite NP is flooded to produce power. Now that they are tearing down Candlestick, we have a perfect place for a nuke in SF.

  7. Kimi Arima says:

    I wrote a similar blog post in October 2012, based on wind data from Spain, Denmark, and Germany for January 2010, see

    Another point about Davey’s comments. It seems a widely held belief among European politicians that a pan-European supergrid would somehow reduce bills. But I have yet to see an honest calculation of the costs of building such a system. Conservative estimates range from €400m to €1,000m+. And how much would that benefit European ratepayers? What’s the payback time for such an investment?

    Not saying that interconnections are useless, quite the contrary. Some level of interconnection is definitely required, but I think the role of interconnections in handling continent-wide demand and supply fluctuations is closer to 5% than 50% of total flexibility needed. Add to this the basic electrical engineering facts of local voltage control and reactive power, and I think it’s safe to say that the Supergrid is not the silver bullet everyone’s looking for.

    Try telling that to, though.

    • Euan Mearns says:

      Kimi, sorry you had problems commenting. Comments are set so that your first comment has to be approved. From now on you should be able to comment no problem. The cost of all this lies at the heart of my objection. If you see the previous post on a Primary Energy Tale you will see that it is a myth that there is vast amounts of energy just waiting to be moved. And moving energy is expensive and incurs losses – so how on Earth can this lower cost. I think the UK probably does need more interconnection with Europe – so that’s fine build another inter-connector but that would most likely import French nuclear – so why not build our own nuclear? The EM 2050 pathway (link below) in fact has 10GW of interconnection with Europe required to be built incrementally between now and 2050 – but shale gas may change that picture.

      Dare I say that getting rid of wind gets rid of the problem of periodic over-supply and that gets rid of the need for a European super grid.

      • Kimi Arima says:

        Euan, no worries, thanks for the prompt action.

        Another blog post I wrote on the interconnection/supergrid idea (see summarizes my ideas a bit further. Quoting myself, ‘The super grid concept relies on the notion that excess output can simply be dumped over the border, and thus investment into flexibility at home is not needed’. Flexibility, in this case, being flexible dispatchable capacity, energy storage, or demand side response.

        And here we hit the current roadblock. While most seem to accept that more flexibility is needed, many have chosen their one favorite solution and are unable to discuss compromises. Witness the supergrid discussion, or the smart grid discussion, or the power-to-gas discussion, or what have you. If the only solution is to (1) build more renewables, while (2) waiting for your favorite not-yet-available technical solution to become reality, then honest realistic discussion about Europe’s energy options become almost impossible.

        It says a lot that a towering character such as James Lovelock criticizes the current energy discussion as being beside the point, and mixing moralistic dilemmas with technical problems. If CO2 is the problem, he said, then drill for shale gas, use it to replace as much coal as quickly as possible, and use the breathing room to ramp up nuclear construction, and worry about the rest later.

  8. Nigel Wakefield says:

    It would be interesting to see the charts for January and June 2013 above with output from solar PV included. I suspect there would be very little difference for January with very little sunshine, but June could could be an entirely different story, since both Germany and Spain have sizable PV capacity installed. France and Italy also have quite sizable installed wind capacity; furthermore Italy’s installed PV capacity is second only to Germany’s in Europe (all from memory).

    Of course, from the perspective of renewables / low carbon generation, we should also consider the output from hydropower (Nordic, Alpine and Iberian) and nuclear….

    It would also be interesting to see an overlay of actual aggregate demand for the (three) countries in question at the time to see the actual contribution of renewables relative to demand in those markets.

    While interesting, the data is not actually that useful unless it can be taken in a pan-European context. France, Benelux, Italy, Scandinavia and Switzerland/Austria/NW Balkans are all reasonable size power markets interconnected (to a greater or lesser extent) with the rest of Europe.

    UK is relatively poorly connected to continental Europe with less than 3 GW of connection (to France and Holland).

    I suspect there is no single place where all the information requested above is accessible, which I think is one of the largest problems when politicians talk about spending billions building massive interconnections here, there and everywhere. Unless we can see where we stand at present, with real time outputs, exports/imports and demand shown in a pan-European context, it is futile to plan such investments.

    The last great stumbling blocks are the facts that a) there is no single continental power market, and b) no single European power grid. Each country or small region operates quasi-independently, both in pricing and dispatch, with the goal, ostensibly, to match, economically, the demand in each region. The politics involved in trying to create a single European grid (and power market) are mind-boggling and the main reason why Ed Davey’s musings are currently little more than wishful thinking.

    Talking of musings, everything I have written above is pretty much off the top of my head and barely begins to scratch the surface of a highly complex problem. If really serious about an interconnected, lower carbon power grid in the future, the EU/UK would do well to spend a few Euros engaging the likes of Bach et al to conduct a thorough review of the status quo. Given free and unfettered access to the most recently available information regarding EXISTING output from wind, hydro, solar, nuclear, as well as cross border flows and aggregate demand, I am sure a small group of experts could build a far more comprehensive picture of the situation than is currently available. If you’re planning a journey, in my experience it’s always useful to know where you’re starting from….

    • Todd Flach says:

      Hi Nigel, Thanks for your very thoughtful comment, I was planning to say something similar until I read your entry at the bottom of this thread.

      As for all the commentary on the theme of this blog, that the hypothesis that
      “The Wind Is Always Blowing Somewhere In Europe.”
      has been successfully rejected, well I say, Congratulations!

      But this hypothesis is not really relevant, as you, Nigel, so craftily yet humbly demonstrated. Wind turbines are not an isolated source of power. And indeed, Euan’s plot shows the month of June, which I suspect, is a very good month for PV production in Spain, southern Germany, southern France, Italy…..all of which could plausibly produce an excess of power for export to northern Europe, if wind power is insufficient there and there is a business case to do so. We in Scandinavia will soon have a massive overcapacity of hydro, nuclear, wind, biomass, natural gas generation capacity, and will also be looking for customers in Northern Europe to take it off our hands for the right price. Especially in June 😉 . A few GW of capacity of power cables are already connect Norway to Denmark and the Netherlands. several more in the planning and permitting stages to Germany and UK.

      • Euan Mearns says:

        Todd, a few years ago cross country skiing in Fjellheimen, N of Finse, Jungdals Hytte, the lake was near empty, as were many Norwegian Lakes, because Norway had contracted to sell electricity to Denmark. The girl who runs the place was in tears, so many trout had died – gone to Green heaven. Norwegian hydro is now beginning a major refurbishment that will boost capacity. But do you know how much wind can actually be balanced off this system?

        With all these inter connectors to Norway I can see the Norwegians sitting there holding an auction each day for peak power. This sounds great for the Norwegian Economy – not so good for northern Europeans who will have to pay for it. Having control here is King. The UK may periodically have surplus wind, but more than likely at a time when many others have similar surplus. So Norway switches off its hydro and runs on dirt cheap wind power that country’s will barely be able to give away. And then the next day sell the water conserved in magazines back to Europe at 10 times the price. I understand why you are enthusiastic about this.

        The UK cannot go on paying for imported energy and needs to make its own.

        • Nigel Wakefield says:

          This was entirely my point about the need for an integrated pan-European grid and power market. None of these grand plans can be made to work, if, as per your example, the Norwegians import (and store) dirt-cheap power and then export it a few days later at a price an order of magnitude higher. All participants need to be able to share equally in the costs and benefits, but this is is not how the system is currently set up.

          I cannot foresee a situation where politicians across the European and Scandinavian spectrum agree to such a system. This would require ceding control of strategic assets to a centralised operator, running the system to optimise in a pan-European fashion, which inevitably would favour some nations at others’ expense at any given moment, and help some more than others all the time. Not going to happen….. so why continue to plan as if it will?? (This should not be construed as personal opposition to such an idea… in theory I think a massive, centrally-operated pan-European grid would be fantastic, but I cannot see it ever happening in practice…)

          In any case, I think the ability of Norway to operate a meaningful part of its system in such a way is constrained to say the least. Purely from memory (and probably a decade out of date), I think less than 5% of Norwegian hydro output is pumped-storage capable. As nothing more than a wild guess, I’d think Norway would have to double generating capacity of its hydrogeneration plant (i.e. twice the turbine capacity running off the same reservoir capacity) to be able to make a meaningful contribution to fill in the intermittency of UK/Germany/Spain’s wind output relative to peak demand at currently installed wind capacity levels .. That’s to say nothing of the increased interconnection required (probably a factor of four times present levels) to meet that demand, nor of the potential demand from the rest of Europe to balance their EXISTING wind portfolio (France, Benelux, Denmark, Italy, etc). Simply put, I doubt Norway has the the reservoir capacity (before investing in extra generation and interconnnection) to balance continental Europe’s exisiting wind fleet… I’d love to hear from someone who’s actually run the numbers…

    • Euan Mearns says:

      Nigel, I am somewhat more positively disposed to solar PV than wind, especially in more southerly latitudes, where solar already shaves much of the day time peak supply in Germany in summer. Looks good? But then you have much higher peak demand in winter and little solar. Brings you back to requiring multiple parallel energy systems – Green as hell IMO. Do you think Germany will continue to expand solar so that they have a summer surplus? The Energiewende is already reported to be in serious trouble, Spanish solar subsidies are in serious trouble, UK solar subsidies (FITs) punish the poor and so on.

      Sharing European hydro sounds great. Everyone wants to balance their wind off Norwegian hydro. I think the comments you make about data transparency are important. I’ve seen reports on the need to harden the European grid etc, vast flows of low carbon energy, but as you probably already know i’ve reached the point where I’d settle for 90GW of nuclear in the UK and be done. From the Scottish perspective we would have 1 new nuke at Torness and 1 new nuke at Hunterston that would probably see us through to 2100. Precludes the need for all the power lines, windmills and biomass everywhere, plus still needing to keep in reserve all the legacy FF plants.

      There is one place in Europe with electricity coming out of its ears and that is France.

  9. Euan Mearns says:

    This is a reply to a comment made on Linked In:

    Jim, this is the chart you referred to. I’m not sure what to make of it. Closely spaced sites have a high degree of correlation – that makes sense. Widely spaced sites no correlation – what does that mean? Data all over the shop? I’ve posted cross plot for UK and Germany below to let folks see what this looks like.

    My understanding of how grid transfers might work is when it is windy one place and not another then power gets transferred. These conditions do exist some of the time, but the question is it worth while building a vastly expensive grid to capitalise on those occasions. Would it really make electricity cheaper? And you still don’t get rid of the need for 100% backup.

    • Roger Andrews says:

      Euan: Here’s a plot of correlation coefficients vs. separation distances for the Table data I supplied earlier. Not knowing where all the wind farms were I winged the separation distances from Google Earth but hopefully they won’t be too far off. Overall the results look very similar to the US plot.

      • Euan Mearns says:

        Roger, Dave R mailed me last night to point out that XL R2 is always a positive number – take note Nigel. Thanks for the plots that look similar to the tundra of the mid west. Would need the gradients as well to make sense of this?

        • Nigel Wakefield says:

          Thanks Euan.

          Coincidentally, having thought about it for an hour or so, I was just about to comment that I could not see how there could be a negative correlation in instantaneous wind output in two areas. I guess if we could measure changes in wind speed, we could end up with negative correlations (increasing in one area while decreasing in another), but not with absolute wind speeds (and consequently output).

          Re-reading the above, I’m not even sure that makes sense, but I’ll put it out there for comment anyway

        • Roger Andrews says:

          Euan; The values I show are R values, not R^2 values, which means they can be negative. The fact that they are all positive means that you can’t balance wind surges in W Europe. All you can do is try to smooth them out as much as possible by adjusting the output from different countries, and the best I’ve been able to achieve is a reduction in the coefficient of variation from 0.49 to 0.43, which I get when 40% of the wind energy comes from Spain, 18% from Ireland, 16% from Denmark, 11% from France, 10% from Belgium, 4% from UK and nothing from Germany (spiky stuff, that German wind power). But even then the situation is hopeless.

          The trends on the graphs also suggest that you would have to go a very long way to find a negatively-correlated wind regime, which is what you would have to hook your supergrid up to to balance your wind output. (Mongolia, maybe? Zimbabwe?) 😉

          • Euan Mearns says:

            OK thanks Roger. I’m guessing that this gross average simplifies a more complex picture. But it thankfully verifies my post title. UK and European energy plan needs to go up a couple gears.

    • Bernard Durand says:

      Euan, I believe that using correlation coefficients is not a good approach, since the relation between power production and wind speed is not linear. Most of the power is delivered during a few days, when wind speed is high enough. During such days, it is likely that correlation between the European Countries is much higher that during days of low speed winds.The approach of Bach and Flocard, which consists in constructing the variations of Wind power production for seven European countries seems to me much better. It shows that adding these productions does not smooth very much the patterns of individual countries. You can see such curves on http://www.sauvonsle (in French, but the curves speak by themselves) when looking at Flocard’s contributions.

      Therefore developing the grid is a waste of money if the aim is only to facilitate the circulation of wind, and solar power. It is also a waste of time, because all this money could be better used during this time to built dispatchable power station or to do research on electricity storage.

  10. Nigel Wakefield says:

    All positive correlations; which is a negative for the need for interconnection argument and a pointer to the need to be able to store or somehow use excess wind power. Simply put, when it’s blowing somewhere in Europe, it’s likely to be blowing to a greater or lesser extent somewhere else in Europe.

    Failing the ability to use or store wind power, it does indeed make little sense to continue to build vast amounts of wind capacity from an economic point of view. The subsidies in the form of FITs, ROCs, etc continue to have effects:
    1. increasing the end-user price of power,
    2. reducing the wholesale price of power
    3. reducing centralised power stations full (and partial) load hours, rendering them increasingly economically and thermally inefficient, leading to
    4. reduction of back up generation available to the grid, which eventually leads to massive price spikes in low-wind (and low solar) peak periods, and possible brownouts and blackouts, ultimately leading to
    5. a positive investment environment for pumped (and other power) storage technologies

    Unfortunately, the environment for pumped storage is currently getting worse not better, from an operator’s economic point of view (see Bach’s article of 29th Spetember 2013 here:

    Wind, on its own, is not the answer to European electricity needs, and the positive correlation for wind output between different areas in Europe shows that more interconnection is not the answer for wind either.

    • Biniput says:

      If points 1 and 2 are correct then surely this is proof of profiteering by power companies and not some problem caused by green technology. How else can the consumer price be lowered than by lower wholesale price? Price spikes have been vanishing like no next week since green tech has got in so that’s surely less of a problem.

      • Euan Mearns says:

        An economist friend brought to my attention the distinction between price and cost. Renewables come at high cost, but periodic over-supply suppresses wholesale price, “everyone makes a loss”. To be honest I don’t understand how the pricing mechanisms work apart from the high costs have to be met – and that is by the consumer. And the consumer is paying increasingly for running two parallel electricity systems – renwables and backup. If you dig up my “Brave Green World” post I cover all the costs currently being funded by the consumer.

    • Euan Mearns says:

      Nigel, its good to see that we seem to agree on a large number of points if not on the solution. Storage is the missing ingredient to make renewables work, but of course storage adds more cost. Running the numbers on Coire Glas was a sobering exercise in scale. Pumped storage works great over a diurnal cycle but scaling to a week becomes unrealistic.

      Having been round all the options I settled on nuclear. Wouldn’t say I was pro nuclear, but given the choice of having electricity or not I would choose the former to a Medieval existence.

  11. Roger Andrews says:

    Going off on another tack, does anyone know how much of the wind power generated in Europe adds to electricity supply and how much merely displaces generation from existing sources, i.e. it adds nothing?

    Another way of posing the question is; how much electricity can Europe generate a) with and b) without wind power? Is there a significant difference?

    • Nigel Wakefield says:


      Logically, the answer to your question must be that wind displaces generation from existing sources (primarily gas, and then coal). In theory, all that displaced capacity is still available to “fill in” the gap between demand and supply from wind/solar, nuclear and hydro (i.e. all the very low marginal cost generation). However, what we are seeing is that plant is being mothballed as it costs more to keep it manned and ready to run than can be made running much decreased hours at lower than historic margins.

      With expensive gas and cheap coal in Europe and very cheap CO2 emissions permits, many of the plants being mothballed are relatively modern and efficient CCGTs, rather than older and less efficient coal plant, though this is changing as coal plant burns rapidly through its other pollution permits (NOX, SOX, etc). The Large Combustion Plant Directive is certainly leading to the closure of much coal plant in the UK which can run much cheaper, though not as environmentally benignly, as CCGT.

      The extent to which back-up is required for when the “wind doesn’t blow” is a much discussed question, and one without any real answer as far as I can see. Clearly, the more wind capacity we have on the grid, the greater the fluctuations will be, particularly in winter, when there are lulls in wind conditions. This is why the UK (and other European countries, as far as I can tell) are introducing “capacity charges” – essentially payments to operators to maintain plant ready to be synchronised to the grid at relatively short notice. These payments will make up the shortfall they are experiencing from lower ruin hours at present. Of course, this will be yet another cost passed on to consumers…. another result of the parallel systems Euan describes.

      In response to a statement upthread from Biniput about lower wholesale prices and higher retail prices being proof of profiteering by utilities, this is NOT the case. The fact is that the subsidies for renewables (eg Feed In Tariffs) are applied to consumer prices ON TOP of wholesale charge. Since renewables are zero marginal cost generators, they displace more expensive plant in the “bid stack” when they are available – this creates the reduction in wholesale prices.. However, the subsidies are far higher in price than the reduction in wholesale prices, hence the higher bills to consumers. This is most evident in Germany, where wholesale prices are generally amongst the lowest in Europe (due to close to 30 GW of both wind and solar installed capacity), while retail prices are amongst the highest, as the FIT costs for all the wind and solar are applied solely at the residential level (industrial and commercial users get a pass…).

      The Energiewende has indeed run into a few problems. It has been so successful in building wind and solar capacity that the big generator companies are close to collapse, as vast amounts of zero marginal cost wind and solar reduce residual demand and crush wholesale margins.

      At the same time, much stress is placed on the grid, as the wind is predominantly in the north and the PV in the south, requiring huge amounts of power to be moved north/south or south/north depending on which renewable is the dominant producer at any given time.

      Lastly, with retail prices so high and community wind and residential solar costs having dropped so much, we find that these renewables are now at or close to grid parity in terms of cost. IE they require little to no subsidy to be worth investing in if you pay retail price for power. This means that even if the FIT is reduced to zero, we will likely see continued development of community wind and residential PV, if just to avoid paying the ever-increasing retail price for power. This will result in even greater excess supply being available in sunny and/or windy times, further stressing wholesale prices.

      Germany is therefore now embarking on a scheme to pay subsidies for the installation of power storage, in an attempt to reduce the energy surpluses hitting the grid, clobbering the generating utilities, and stressing the wires. The idea being that the more renewable production of one’s own that one can use, the better it will be for all. I suspect this will result in large amounts of diurnal storage capacity being installed in the way of batteries (not good for remaining conventional baseload plant in summer) – which hopefully will lead to reductions in cost for shorter-term battery based storage solutions and improvements in life-cycles.

      Germany’s Energiewende is a very interesting experiment which could yet be a fantastic and astonishing success or a disastrous failure. It almost seems to be leading to two parallel systems: wholelsale generators catering to the large-load industrial and commercial sectors, with small commercial and residential sectors targeting self-sufficiency through distributed generation, small scale storage, community ownership of local distribution networks and development of smart local grids…

      • Kit P says:

        While looking at the time correlation between wind production and demand, another time factor should be considered. How does the production of power decrease with time. We are building wind and solar because LCA done 20 years ago says a reduction in ghg will be achieved. There is an amazing lack of bragging about performance by the wind and solar industries. There was a program in the US to document voluntary reductions in ghg. Coal and nuke plants were the huge leaders. The reason is that improving performance was very good economicly. US nuke plants are performing much better that what was assumed in LCA.
        If you compare at the rate of building new wind and solar to the rate of decrease in wind and solar power production, too much wind and solar will never be a problem. To put it simply, stuff breaks. When a nuke plant breaks, it gets fixed ASAP because replacement power is on the order of a million dollars a day. When a wind turbine or solar panel stops working, it gets put on a to-do-list. If the cost of fixing it is more than value of the power produced, it never gets fixed.

      • Roger Andrews says:

        Nigel: Thank you for that explanation.

        I’ve been doing some work with the numbers and have found that capacity factors for conventional generation in Europe have decreased over the last few years while electricity generated by wind and solar has increased roughly in proportion. This tends to confirm that wind is indeed displacing generation from existing sources rather than adding “new” electricity.

        Although as you point out, generation from existing conventional facilities can always be increased if demand increases, provided of course that the facilities are still there.

        I’m beginning to think of wind power as a loose cannon rolling around the deck of the European electricity market, taking off in unpredictable directions, crashing into bulkheads and now threatening to sink the ship altogether. I’m not sure the people who let the cannon loose in the first place had any idea of what was going to happen, but if the big generator companies in Germany really are close to collapse because zero-marginal-cost wind and solar power is making their business unprofitable, and if wind and solar surges really do make it cheaper to mothball perfectly good generation facilities than to keep them running then the situation is serious indeed.

        • Nigel Wakefield says:


          I must stress that it’s the gencos within the German utilities, rather than the utilities as a whole, that are struggling. The transmission and distribution businesses are doing very well and the supply businesses are holding their heads up.

          One of the reasons for falling wholesale margins is that residual demand (i.e that portion of demand not catered for by nuclear, hydro, wind and solar) has fallen more quickly than the amount of conventional generating capacity capable of meeting it. The conventional generators are therefore competing more aggressively between themselves to keep their kit “on the bars”. Ostensibly, such competition is a good thing, and, I would think, an intended consequence of the Energiewende and other renewable build-out programmes.

          The problem arises when numerous assets are mothballed or shut down entirely, as this will reduce competition between generators and, potentially dramatically, increase the price of power during demand spikes or renewable shortfalls, thereby once again raising average wholesale prices and bringing mothballed plant back online. That’s how things are supposed to happen with free-market capitalism…. though I think critical and essentially mono/oligopolistic utilities (power, heating, water) do not belong in a “free market” system: free markets create short term price signals and knee-jerk reactions, the absolute opposite of what is needed when planning multi-billion [$, €, £] investments to operate over several decades. The more uncertain the financial operating environment, the more expensive the finance available to build the asset…. of course, the banks love it….

          I tend to agree that there have been a lot of unforeseen consequences as a result of the massive increase of renewable energy, and in particular wind. Solar is far more predictable both on a seasonal and shorter-term basis and serves well to meet higher demand periods in summer. With a wide geographical spread of solar installations, intermittency caused by passing clouds is not much of a problem and cloudy days can be forecast and therefore prepared for in advance.

          Forecasting for wind has improved massively over the past decade, such that reasonable forecasts can now be made 10 days ahead, and forecasts with >95% accuracy 24 hours ahead (this is claimed by National Grid in the UK). Scheduling other plant to come online (or offline) in strengthening and weakening winds is therefore not too much of a problem… it’s the continued availability of such plant is such a dire operating environment that’s causing the headaches. As I said, capacity pricing mechanisms are being introduced to ensure that such assets will continue to be available.

          There is a clear feel of “making it up as they go along”, but I don’t think the situation is as bleak as some make it out to be.

        • Roger Andrews says:

          Nigel: Some comments on your comments:

          “I must stress that it’s the gencos within the German utilities, rather than the utilities as a whole, that are struggling. The transmission and distribution businesses are doing very well and the supply businesses are holding their heads up.”

          But if the gencos go belly-up there’s no electricity to transmit and distribute.

          “I think critical and essentially mono/oligopolistic utilities (power, heating, water) do not belong in a “free market” system”

          I’m inclined to agree with you. In the US the historic approach of granting a state-regulated utility a monopoly over power distribution in its service area and a guaranteed return on investment (which it didn’t always get) worked pretty well. Then along came privatization, and Enron ….

          “The conventional generators are therefore competing more aggressively between themselves to keep their kit “on the bars”. Ostensibly, such competition is a good thing, and, I would think, an intended consequence of the Energiewende and other renewable build-out programmes.”

          I very much doubt that this was an intended consequence. The Energiewende is described by Wikipedia as “the transition by Germany to a sustainable economy by means of renewable energy, energy efficiency and sustainable development” with the “final goal (being) the abolition of coal and other non-renewable energy sources”. The Green visionaries who come up with utopian plans like this don’t think in free-market terms. If they did they wouldn’t come up with them.

          “I tend to agree that there have been a lot of unforeseen consequences as a result of the massive increase of renewable energy, and in particular wind.”

          The increase in wind energy that caused these unforeseen consequences has actually been very small. In 2010, the last year for which I have EIA data, less than 5% of the electricity generated in Europe (153 of 3,610 Twh) came from wind. And if a 5% increase can cause so many distortions what’s going to happen in 2050, when wind is scheduled to supply 50% of Europe’s electricity?

          “Solar is far more predictable both on a seasonal and shorter-term basis and serves well to meet higher demand periods in summer. With a wide geographical spread of solar installations, intermittency caused by passing clouds is not much of a problem and cloudy days can be forecast and therefore prepared for in advance.”

          Solar in Europe is a pimple on the elephant’s backside. In 2010 solar, tide and wave power combined supplied less than 1% of Europe’s electricity (24 of 3,610 Twh, and at a capacity factor of less than 10%, incidentally).

          “Forecasting for wind has improved massively over the past decade, such that reasonable forecasts can now be made 10 days ahead, and forecasts with >95% accuracy 24 hours ahead (this is claimed by National Grid in the UK). Scheduling other plant to come online (or offline) in strengthening and weakening winds is therefore not too much of a problem… “

          Wind forecasting, no matter how accurate, won’t allow us to smooth out wind power surges. All it will do is tell us a day or two in advance how large the surges will be. As discussed upthread it’s impossible to smooth out wind power surges in Europe by interconnecting wind farms or installing smart grids or anything else. The only way wind power can be made dispatchable is by storing it in pumped hydro plants or batteries for reuse. Otherwise wind surges can be integrated into the grid only by shutting other generation sources down, and there are obviously limits as to how far we can go with this.

          “There is a clear feel of “making it up as they go along”, but I don’t think the situation is as bleak as some make it out to be.”

          I agree with the first statement. On the second, I acknowledge that crisis situations rarely turn out to be as black as they’re painted, but from a distance of 5,000 miles it sure looks to me as if Europe is heading off a cliff.

          • Bernard Durand says:

            Roger, forecasting for wind, and even for solar is never acurate to the point that you can predict the exact number of GW you have to put or to substract instantaneously into the grid if reality is not in agreement with prediction.
            Flocard has shown for the German case that the gap coud be as much as 11 GW, that is to say about 20 coal or gas fuelled power stations! This was 2 years ago! Now it should be more.

  12. Nigel Wakefield says:

    Following Roger’s comments re wind and solar penetration in Europe as of 2012, I tried to find some more recent numbers – surprisingly difficult to get anything up to date…

    Best guesses for European installed capacity as at end 2013 are as follows:

    Wind 116 GW (~38% higher than end 2010)
    Solar PV 80 GW (~176% higher than end 2010)
    Concentrated Solar Power 2 GW (300% higher than end 2010)

    There’s some very up-to-date data for Germany here:

    Germany: total installed capacity and production as at end 2013:
    Wind 33 GW, producing 47.2 TWh,16.3% average load factor, ~8% of total consumption
    Solar PV 35.5 GW, producing 29.7 TWh, 9.55% average load factor, ~5% of total consumption

    The load factors for wind are fairly dire, for PV they are pretty much what I’d expect.

    Total subsidy cost for ALL renewables (i.e. including hydro and biomass), which account for ~25% of all electricity production was approx €19 billion on production of ~150 TWh.

    “German power prices extended their downward trend in 2013 with spot power on average 13% lower than in 2012, while year-ahead prices fell to their lowest level in over eight years due to oversupply from renewable and conventional sources as well as cheaper generation costs and falling demand.

    According to Platts data, German day-ahead, over-the-counter power prices for baseload delivery averaged Eur37.51/MWh in 2013.

    The average 2013 closing price for OTC year-ahead baseload power was Eur39.06/MWh, down 21% or more than Eur10 from the 2012 average of Eur49.27/MWh.”

    If you smear the €19 billion renewable subsidy cost across total consumption of 596 TWh for 2013, the effect of renewables is to add ~€32/MWh to wholesale baseload prices of €37.51, leading to an average subsidy-included baseload price of approx €69.40 for 2013.

    This is, of course, a simplistic way of looking at things, since very little of the 150 TWh of renewable output would have been baseload power (most of the biomass, some of the hydro and a very small part of the wind), but it does go to show that the cost of renewables exceeds the reduction in wholesale costs, probably by about €20/MWh or thereabouts.

    That said, the renewables-included cost of €69.40/MWh compares favourably to the price agreed by the UK government for new nuclear power (£92.50/MWh or ~€111.0/MWh) in 2013 money.

    There are obviously differences between the German and UK markets (UK baseload prices are higher and installed renewables far lower as a percentage of total generation both by output and capacity). As an example, year ahead price assessments for UK baseload are at €63.00 and for Germany at €37.65, a difference of €25.35/MWh.

    I estimate renewable energy subsidies and programmes to comprise about 11% of UK retail power prices, which equates to roughly £14/MWh or €17/MWh. In Germany, for 2014, the cost will be about €35/MWh.

    All in, therefore, wholesale + renewables subsidies, German prices for 2014 are roughly €72.65/MWh and UK prices are €80.00. The major difference, however, is caused by the fact that UK peak prices are generally set by CCGT whereas in Germany they are predominantly set by coal units.

    Either way, both look cheap in comparison to the CFD strike price for new nuclear build. Of course, if gas prices rise, as I expect them to over the next decade, nuclear may wind up looking comparatively cheaper, though it should be noted that the strike price of £92.50/MWh will rise with inflation (CPI, I think??) until the plant is actually commissioned some time in the mid 2020’s….

    • Roger Andrews says:


      According to the Platts report “Power consumption (in Germany) fell 2013 for a third year in a row, down 1.8% year on year at 596 TWh.” Is this a result of the ongoing economic slowdown or are other factors at work?

      This report hot off the press might be of interest to you:

      “Solar and wind advocates often point to the falling electricity prices in Germany as a sign that the Energiewende is working and intermittent renewables are not as expensive and impractical as critics claim. However, as this article will strive to demonstrate, quite the opposite is true. Falling electricity prices offer a good demonstration of how quickly the market discounts intermittent renewables as penetration increases, thereby further eroding the already poor competitiveness of these electricity sources.”

  13. Nigel Wakefield says:

    I think the drop in power consumption is both a product of both the economic slowdown and a reflection of the fact that the increase in distributed generation (i.e. onsite power, whether renewable or not) leads to a reduction in grid power requirements. As an example, my own grid-imported electricity use has reduced dramatically in the two years since I installed 4 kW of PV at my house – this is because I use my own power when I’m generating it and also I have changed my usage patterns to maximise the use of the PV electricity I generate.

    The report was interesting to read from a statistical point of view, but hardly news to me. It is self-evident that increased penetration of renewables will lead to lower wholesale prices, since wind and solar are zero marginal cost producers. I have made this point before.. Given that the majority of income from these renewables comes from the Feed In Tariffs, the lower income from wholesale prices is largely irrelevant to them (though obviously not for conventional generators). Since the cost of the FITs is smeared (mostly) across the residential sector, the lower wholesale prices are not reflected in lower retails prices – another point I have made previously.

    This results in a situation where relatively high retail prices (circa €0.25/kWh in Germany) are sufficiently expensive to encourage increased installation of renewables (particularly PV) irrespective of the low cost of wholesale power and irrespective of much lower FIT subsidies. Indeed, with lower PV installation costs and higher retail prices, it is arguable that PV at a residential level in Germany is probably already at grid parity and more capacity would continue to be installed even if FITs were reduced to near zero levels.

  14. Bernard Durand says:

    Nigel, grid parity can be obtained either by decreasing the cost of solar PV or by increasing the retail price. Both are done in Germany. Grid parity is still not obtained in France, where retail prices are for the moment half of german ones. Nevertheless, there is a limit in such a system, which is the very low load factor of solar PV. Nobody can be electrically autonomous this way in Germany especially during winter, even by changing completely his consumption pattern. Is not there a risk to see the development of generating units powered by Russian gas to assist PV or wind in “autonomous” communities?
    Germans have so much developped PV and wind in a few years that they have already a power capacity of roughly 65 GW . This value is roughly the same than for nuclear in France, but with a mean load factor which is 5 times less! This will result in an increase of the retail price of electricity not only in Germany, but also in the countries which are connected to Germany by the European Grid!

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