Technical and Economic Analysis of the European Electricity System with 60% RES – A Review

Guest post by Dr Phillip Bratby who reviews the EDF R&D Paper ‘Technical and Economic Analysis of the European Electricity System with 60% RES, by Alain Burtin and Vera Silva, 17 June 2015’

Dr Phillip Bratby BSc, PhD, ARCS, MNucI has spent most of his career in the civil nuclear industry, working in the areas of the safety and operation of water reactors.  Before retirement he was an in independent energy consultant.

Download the EDF report Technical and Economic Analysis of the European Electricity System with 60% RES from Energy Post.


The EU has a strategy to increase the amount of electricity that will be generated from renewable energy sources (RES) to 55% by 2050. About 57% of the RES in Europe is currently hydro and there is little opportunity to expand hydro. Thus most of the projected increase in RES, which constitutes about 10% of electricity generation in 2014, will be from wind and solar PV, reaching 20% in 2020 and 30% in 2030. The EDF paper examined the future impacts, challenges and changes to the power system of increased wind and solar PV renewable energy sources (variable RES) on the European electricity grid…..

The paper examined a High RES scenario taken from the EU Energy Roadmap 2011. Assumptions concerning low carbon generation (RES and nuclear) were taken from the Roadmap, with 60% of electricity coming from RES by 2030, of which 40% would be variable RES.

In this review I have not examined the financial implications of the high RES scenario.

Analysis and Results

The intermittent (variable and uncertain) and non-dispatchable output of wind and solar PV are well understood. Using 30 years of weather data across Europe, the EDF paper studied the impact of 60% RES (40% variable RES) generation across Europe at differing timescales, from hourly, to seasonal and to inter-annual.

As expected, this showed for wind power that the intermittency is greatest at a local level, but is reduced at regional, national and European level.

Seasonal variability is such that load factors average about 25% but vary from 15% in summer to 30% in winter. Even at a European level, wind regimes show a strong correlation and there remains considerable variability. For example, with 280GW installed wind capacity across Europe, the average daily wind generation in winter varies between about 40GW and 170GW (a range of about 130GW, incorrectly labelled 90GW in the graph below).

Similar results were obtained for solar PV, with less variability as the geographical area is increased from a solar farm to a county, to a region and to a country.

With a total European installed capacity of 220GW, the average load factor is 13%, the daily variability is less than for wind power, and the load factors are 5% in winter and 20% in summer.

It was concluded that the integration of wind and solar PV poses two challenges:

  1. managing intermittency at the local distribution network level (not part of the study);
  2. handling variability at a fully developed Europe-wide interconnected distribution and transmission system (the handling of variable RES within national distribution and transmission systems is not part of the study).

Currently, variable RES (wind and solar PV) have priority access to the system, and the volume of production has so far only had a marginal impact on the system. However, the large scale introduction of variable RES will have a marked impact on the structure and operation of the electricity system at all levels. The paper examined the infrastructure requirements (inter-connectors, reinforcements), on existing generators, on the flexibility (storage, stability and demand) and costs/profits in order to accommodate 40% variable RES (wind and solar PV).

For the study of the high RES EU scenario of 60% renewable electricity by 2030 it was assumed that 20% of the electricity would come from hydro and biomass and 40% of the electricity would come from variable RES (wind and solar PV). The remaining 40% would come from nuclear and fossil fuels, with a nuclear capacity of 90GW, as given by the EU Energy Roadmap 2011. The EDF paper examined the feasibility of integrating this level of variable RES into the system and what the impact on fossil fuel generators would be.

It was assumed that variable RES across Europe would be distributed to prioritise best usage of the resource, whilst accommodating land usage and other social constraints. Thus onshore wind is spread across the whole of Europe, with offshore wind mainly in the north and solar PV mainly in the south. Interconnector developments were assumed necessary to transfer production to demand centres and reduce back-up requirements.

The study recognised that because wind and solar PV are variable and difficult to forecast, because electricity cannot easily be stored and because generation has to be balanced with demand at all time, the integration of a high proportion of variable RES will pose a number of challenges across the entire electrical system. A variety of computation tools were used to perform system-wide studies.

In the study it was assumed that in 2030 total demand is 3600TWh/year with a peak demand of 600GW.

The 40% of electricity (1440TWh/year) from 700GW of variable RES is provided by:
220GW of solar PV with a load factor of 13%
280GW of onshore wind with a load factor of 22%
205GW of offshore wind with a load factor of 36%
20% of the electricity (720TWh/year) is from hydro, biomass and geothermal.
40% of the electricity (1440TWh/year) is from fossil fuels and nuclear.

The results of the study showed the following:

1. Variable RES contribute to providing electricity but make a minor contribution to capacity.

2. 700GW of variable RES displace 160GW of baseload but increase backup by 60GW. The 700GW of variable RES thus lead to reduction in conventional capacity of only 100GW. The reduction of 100GW is solely due to wind since solar PV displaces 20GW of baseload and requires 20GW of backup (the capacity credit of solar PV is zero). Thus the capacity credit of wind is 20%, a figure which falls as wind capacity increases.

3. Nuclear capacity is assumed to remain unchanged at 90GW, as given by the EU Energy Roadmap 2011. Coal capacity is reduced by 170GW from 250GW to 80GW. CCGT is increased by 15GW from 70GW to 85GW. OCGT is increased by 65GW from 35GW to 100GW.

4. There will be periods (unspecified) when variable RES exceeds demand and curtailment is required in order to maintain generation/demand balance and to allow the provision of reserves and ancillary services required to ensure the security of the system.

5. Operation of the electricity system will be challenging, with traditional flexible sources no longer available and limited providers of ancillary services.

6. CO2 emissions are significantly reduced (1Gt/year) compared to a scenario without variable RES. However this figure is derived simply from the net reduction in fossil fuel usage from 40% of generation to 20% of generation (a reduction in coal usage but an increase in gas usage) and does not take account of the carbon footprint of the variable RES and of the infrastructure developments. The impact on backup emissions is low because backup is mainly provided by dispatchable hydro. There is limited usage of the OCGT for peaking, with operation only being necessary for a few hours a year. Coal usage continues at a much reduced level, but is not eliminated because the price of CO2 is not high enough to remove all coal plants. Further reductions of emissions would occur if the coal usage were completely replaced by gas usage.

7. Variable RES increase the system variability that needs to be managed by conventional generators. The net demand (defined as the real demand less the variable RES generation) is much more variable than the real demand, consisting of more frequent large variations in net demand. Upward hourly variations larger than 20GW and downward variations larger than 10GW increase by 50% and extreme hourly variations of >70GW now occur. Real daily demand varies by between 100 to 200GW, whereas net demand varies by over 400GW.

8. The variable RES are dependent on weather conditions such that the electricity generated can vary by 5TWh between the same day in different years (equivalent to 200GW capacity). The demand variation due to temperature conditions is only 2TWh (equivalent to 80GW) in winter and 0.7TWH (equivalent to 30GW) in summer. Increased load balancing is necessary to cope with this increased sensitivity to weather conditions and there will need to be a significant increase in operating margins.

9. Improved weather forecasting would reduce the operating margins and reserves needed to cover the uncertainty in variable RES generation. An integrated system across Europe would reduce the uncertainty by a factor two.

10. An island grid, such as that of the UK, would benefit from the further interconnectors, the reduced uncertainty of an integrated grid and increased security margins. However, with HVDC interconnectors, the management of frequency control would pose particular difficulties for the UK at 40% variable RES. An operating reserve of about 6GW would be required in the UK at 40% variable RES.

11. The increase of asynchronous generation (an electronically controlled interface between the generator and grid) of variable RES will lead to a reduction in system inertia and thus reduce the robustness of the system to faults. This is of particular concern during periods of low demand.

12. Demand response mechanisms and storage increases only have a small impact on the need for backup capacity, but can contribute to management of the system in terms of frequency control and grid balancing.

Key findings

1. Regardless of how much variable RES is installed, thermal generation remains necessary in order to ensure system stability and security of supply.

2. Nuclear power is a necessary part of the thermal generation if CO2 emissions reduction targets are to be met.

3. New (unspecified) mechanisms will be needed to manage a large amount (40%) of variable RES, to maintain stability and ensure security of supply.

4. To achieve 60% of Europe’s electricity generation from RES (20% from hydro and biomass and 40% from variable RES (wind and solar PV)), about 500GW capacity in total of thermal (350GW), hydro (120GW) and biomass (30GW) and about 700GW of variable RES capacity will be needed.

5. 700GW of variable RES will result in large variations in daily variable RES production, by up to 50% of European total demand. Extreme hourly variations in net demand (>70GW/hr) will occur, with frequent upward and downward variations of >20GW/hr and >10GW/hr respectively.

6. There will need to be an increase in network infrastructure at local (distribution) , national (transmission) and intra-national (inter-connectors) levels.

7. Demand response mechanisms will need to be developed.

8. The security of supplies will become a more important issue as synchronous generators are replaced by asynchronous generators.

9. Island grids (such as Ireland and the UK, connected to Europe by HVDC interconnectors) will have particular difficulties with frequency control.

10. In order to meet CO2 emissions targets, low carbon conventional generation is needed; increased usage of nuclear power is the best option.

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78 Responses to Technical and Economic Analysis of the European Electricity System with 60% RES – A Review

  1. Euan Mearns says:

    Hi Phill, thanks for this interesting summary. A couple of observations. In the first figure the order of “variability” seems to be:

    1. Farm
    2. France
    3. Brittany

    I’m not sure I understand what the following means:

    Thus the capacity credit of wind is 20%, a figure which falls as wind capacity increases.

    Can you perhaps explain.

    And from the map, its not clear to me that an additional 7.5GW of interconnection between UK and Europe will do much to get rid of 82GW of offshore wind supply.

    And I like the last diagram. I think many of us would benefit from further clarification of “system inertia” and “asynchronous” supply. For example, are nukes more sensitive to trip in a metastable supply situation?

    Finally, EDF really ought to get more pro nuclear IMO.

    • Peter Lang says:


      If you haven’t seen it there is an excellent post by Planning Engineer on Climate Etc.: Renewables and grid reliability

      Key Points

      • There has been a high value placed on having an extremely reliable bulk grid as the costs and consequences of bulk grid outages are severe
      • The bulk grid supports and is supported by conventional rotating generators (Coal, natural gas, hydro, nuclear, biomass) which provide “Essential Reliability Services” (ERSs)
      • Wind and solar provide increased reliability risks because they are new changing technologies, they are intermittent and they do not as readily provide ERSs
      • Current high levels of reliability depend upon experience gained over time through the gradual adoption of new technologies
      • Wind and solar can be made to provide approximations of ERSs, but that requires significant increased costs and reduced generation output
      • Because of the complexity of impacting factors and the high level of reliability maintained for the US grids, systemic degradation of the reliability of the grid is hard to detect and measure
      • The amount of renewable penetration that can be accommodated will vary from area to area and power system to power system – There is not a single answer
      o Because conventional resources produce an abundance of ERSs, accommodation of low levels of renewables may be accomplished with negligible risks
      o Because current renewables do not provide adequate ERSs high penetration levels provide significant risks
      o Between the above two levels there is a gap of (wicked?) uncertainty.
      • For assessing grid reliability, the maximum penetration of wind and solar during times of stress is the key number not the “average” contribution of wind and solar
      • Increased penetration of such asynchronous resources, all else equal, will likely adversely impact bulk grid reliability
      • As the penetration level of asynchronous generation increases this will either increase cost, limit operational flexibility, degrade reliability or most likely result in a combination of all three factors

      The above statements have the following important caveats

      • In some situations renewable resources may have some practical benefits and better support reliability in some limited applications For example:
      o Air quality standards often prohibit the location of new generation resources in congested areas. If renewable resources are allowed to be located close to load centers –the system may see benefits
      o Electronic emulation of ERSs in some cases will not be as good as actual synchronous machines, but with proper controls it may also be better in some cases
      • Given time the reliability risk associated with new technology can be reduced as more experience is gained so that penetration levels can be increased

    • Euan: Peter Lang has essentially answered your question. The capacity credit is based upon risk, i.e. the Loss of load Probability (LOLP). Essentially, the more wind there is and the more dispatchable capacity has been removed, the more likely is the risk of loss of load when more wind capacity is added, hence its credit is less.

      The 82GW of UK offshore wind would be a disaster. Even with the increased interconnectors it would require massive curtailment. I don’t think that the study goes into the depth of whether the proposed interconnectors are compatible with the assumed distribution of variable RES. The interconnectors shown are those which have been determined to have a positive cost-benefit.

      From memory, the reactor protection system for Sizewell B is is such that it is sensitive to grid frequency and stability. Protecting the reactor is more important than protecting the grid.

      As I understand it, I think EDF has two problems: the current French Government is anti-nuclear and seems determined to stop further developments in France, even though nuclear is the best ‘low carbon’ technology; secondly, it only has the EPR design of AREVA to sell, and it is proving to be a disaster at Olkiluoto and Flamanville and is far too expensive at Hinckley.

      • David McCrindle says:

        I have never understood why we (or the French) are going for very expensive EPRs. Why are we not just replicating the existing successful, safe PWR designs? Sizewell B, Gravelines or whatever. The argument seems to be based around passive safety, but reliable well designed active safety is just as good really. After all, we (apart from the Germans – and there is still time for them to change their minds) are quite happy to run the existing PWRs for many years to come.

        • robertok06 says:

          Greenthink has permeated so well the institution of Europe that the existing reactors’ design would never pass the veto of the various nuclear safety agencies… just think of France after Fukushima… the ASN (Agence pour la Surete Nucleaire) has obliged EDFto install “Fukushima-like” safety measures!… even for reactors placed away from the sea/ocean…

          • David McCrindle says:

            Yes, but don’t we need to change this by campaigning and educating our nuclear regulators. They are after all well paid, intelligent people and the concepts of balancing risk and overall ALARP across the whole of society should not be beyond them.

            They are there to prevent large scale accidents such as the Windscale fire and Chernobyl, but in practise they have also forced large expenditure on the prevention of minor things (accidents that might give small operator doses or criticalities in well shielded facilities). I think that they are now learning that this approach is sub-optimal. Large sums of money have been spent preventing minor consequences, money that from a risk point of view would have been better spent on improving road safety or employing more doctors.

            They might therefore be open to persuasion that making power stations cost too much by overregulation will mean that none are built at all, something that may be very bad for society.

          • robertok06 says:


            “Yes, but don’t we need to change this by campaigning and educating our nuclear regulators. ”

            I wish they listened to you but…



        • cafuccio says:

          Don’t forget that Siemens was part of the design before they left. Parts of choices were made in a German context, not French one. That said, concerning the Finnish one, the regulatory context explains most of the delay: the plant is paid by paper industry, not the Finnish state. They knew nothing of nuclear safety at first (and not much now neither). They asked for the moon. Moreover areva wanted to lead, without experience.
          For the French one, there was engineering issues and planning mostly, but finally come to an end. The plant was initially planned in Penly, but Mr Fabius decided not to go. Flamanville has different geography

    • Willem Post says:

      Wind and solar only have a capacity credit for LONG TERM planning of generator population for a grid.
      Texas, which has over 15000 MW of wind capacity credits 8.7% of that capacity for long-term planning. See page IV.

      It has nothing to do with dispatch to produce energy at a moments notice.

      With increasing wind and solar and less traditional, there will be much less synchronous, rotational inertia on the grid, which acts as a stabilizer.

      Various studies have been made regarding simulating synchronous inertia. Implementation of it may occur in the future.

      • Peter Lang says:

        Capacity credit of wind power in South Australia and Victoria are about 8% and 3% (forgotten which order that is).

  2. Peter Lang says:

    Dr Phillip Bratby,

    Thank you for this informative post. I have a comment and a question about two sentences.

    However this figure is derived simply from the net reduction in fossil fuel usage from 40% of generation to 20% of generation (a reduction in coal usage but an increase in gas usage) and does not take account of the carbon footprint of the variable RES and of the infrastructure developments.

    More significant is the reduction on CO2 abatement effectiveness of variable renewables as their penetration increases. CO2 abatement effectiveness decreases to about 50% at around 20% penetration. It is important to take CO2 abatement effectiveness into account in the analyses of CO2 amissions avoided – very few analyses seem to do so.

    The impact on backup emissions is low because backup is mainly provided by dispatchable hydro.

    Does the analysis take into account the hydro storage capacity limitations? Hydro is very valuable for grid stabilisation and black-start capability – without knowing anything about the European grid I would expect the role hydro plays now could not change much as it’s share of electricity does not increase.

    • Peter: I agree with you that CO2 abatement effectiveness decreases to about 50% at around 20% penetration. This has been shown by analysis of the grid in Ireland. I agree that It is important to take CO2 abatement effectiveness into account in the analyses of CO2 emissions avoided, but it has so far been impossible to convince the Government of this. They are too influenced by the wind lobby and civil servants – or they realise the truth but daren’t admit what an expensive folly wind power is. I suspect the former.

      With regard to hydro, I don’t think the analysis goes into that detail. It assumes that the current hydro capacity in Europe will continue and that it will be used as a dispatchable backup to variable RES to maintain stability.

    • Willem Post says:

      Here is the situation regarding the effectiveness of wind reducing CO2 emissions. Brussels knows about it, but prefers to stick with its ad hoc/arrived-at-in-committee factors approach.

      Ireland’s Power System: Ireland had an island grid with a minor connection with the UK grid until October 2012. Eirgrid, the operator of the grid, publishes ¼-hour data regarding CO2 emissions, wind energy production, fuel consumption and energy generation. Drs. Udo and Wheatley made several analyses, based on 2012 and earlier Irish grid operations data, that show clear evidence of the effectiveness of CO2 emission reduction decreasing with increasing annual wind energy percentages.

      The Wheatley study of the Irish grid shows: Wind energy CO2 reduction effectiveness = (CO2 intensity, metric ton/MWh, with wind)/(CO2 intensity with no wind) = (0.279, @ 17% wind)/(0.53, @ no wind) = 0.526, based on ¼-hour, operating data of each generator on the Irish grid, as collected by SEMO.

      If 17% wind energy, ideal world wind energy promoters typically claim a 17% reduction in CO2, i.e., 83% is left over.

      If 17% wind energy, real world performance data of the Irish grid shows a 0.526 x 17% = 8.94% reduction, i.e., 91.06% is left over.

      What applied to the Irish grid would apply to the New England grid as well, unless the balancing is done with hydro, a la Denmark.

      Europe is facing the same problem, but it is stuck with mostly gas turbine balancing, as it does not have nearly enough hydro capacity for balancing.

      Fuel and CO2 Reductions Less Than Claimed: If we assume, at zero wind energy, the gas turbines produce 100 kWh of electricity requiring 100 x 3413/0.5 = 682,600 Btu of gas (at an average efficiency of 0.50), then 682600 x 117/1000000 = 79.864 lb CO2 are emitted.

      According to wind proponents, at 17% wind energy, 83 kWh is produced requiring 83 x 3413/0.50 = 566,558 Btu of gas, which emits 566558 x 117/1000000 = 66.287 lb CO2, for an ideal world emission reduction of 13.577 lb CO2.

      In the real world, the CO2 reduction is 13.577 x 0.526 = 7.144 lb CO2, for a remaining emission of 79.864 – 7.144 = 72.723 lb CO2, which would be emitted by 621,560 Btu of gas; 621560 x (117/1000000) = 72.723 lb CO2.

      To produce 83 kWh with 621,560 Btu of gas, the turbine efficiency would need to be 83 x 3413/621560 = 0.4558, for a turbine efficiency reduction of 100 x (1 – 0.4558/0.50) = 8.85%.

      Below is a summary:

      Ideal World…………………………..Btu…………CO2, lb…….Turbine Efficiency
      No Wind gas generation………..682,600………79.864……………0.5000
      17% Wind gas generation……..566,558……….66.287…………..0.5000

      Real World
      17% Wind gas generation……..621,560……….72.723…………..0.4558

      Actually, Ireland’s turbines produce much more than 100 kWh in a year, but whatever they produce is at a reduced efficiency, courtesy of integrating variable wind energy.

      For example, in 2013, natural gas was 2098 ktoe/4382 ktoe = 48% of the energy for electricity generation; see SEIA report. This likely included 2098 – 2098/1.0855 = 171 ktoe for balancing wind energy, which had a CO2 emission of about 171 x 39653 million x 117/million = 791.4 million lb. This was at least 791.4 million lb of CO2 emission reduction that did not take place, because of less efficient operation of the balancing gas turbines.

      The cost of the gas, at $10/million Btu, was about 171 x 39653 million x $10/million = $67.6 million; it is likely there were other costs, such as increased wear and tear. This was at least $67.6 million of gas cost reduction that did not take place, because of less efficient operation of the balancing gas turbines.

      In 2013, the fuel cost of wind energy balancing was 5,872,100,000 kWh of wind energy/$67.6 million = 1.152 c/kWh, which would become greater as more wind turbine systems are added.

      It must be a real downer for the Irish people, after making the investments to build out wind turbine systems and despoiling the visuals of much of their country, to find out the reductions of CO2 emissions and of imported gas costs, at 17% wind energy, are about 52.6% of what was promised*, and, as more wind turbine systems are added, that percentage would decrease even more!!

      *Not included are the embedded CO2 emissions for build-outs of flexible generation adequacy, grid system adequacy, and storage system adequacy to accommodate the variable wind (and solar) energy, plus all or part of their O&M CO2 emissions during their operating lives; in case of storage adequacy, all of O&M CO2 emissions, because high wind and solar energy percentages on the grid could not exist without storage adequacy.

      NOTE: Gas turbine plant efficiencies are less at part load outputs. If gas turbines plants have to perform peaking, filling-in and balancing, due to variable, intermittent wind and solar energy on the grid, they generally operate at varying and lower outputs and with more start/stops. Such operation is less efficient than at steady and higher outputs and with fewer start/stops, just as with a car. Operation is unstable below 40%, hence the practical limit is about 50%, which limits the ramping range from 50% to 100%. Here is an example:
      Simple Cycle………………….100%……….38%……………..40%………….26%
      Combined Cycle……………..100%……….55%……………..40%………….47%

      Australia’s Power System: The Wheatley report states, with 4.5% wind energy on the grid, CO2 reductions were about 3.5%, which means the effectiveness was about 3.5/4.5 = 78% in 2014. The Wheatley report states, if wind energy were 9%, it would be about 70%. By extrapolation, if wind energy were 13.5%, it would be about 62%, and at 18%, it would be about 54%, i.e., the more wind energy, the less its effectiveness reducing CO2 emissions and fuel consumption. This would be similar to the effectiveness of 52.6% at 17% wind energy of Ireland’s power system. The laws of physics apply to Ireland, Australia, etc.

      • Peter Lang says:

        Willem Post, you don’t need to keep telling me about the Wheatley study of Ireland as if I don’t know. In case you don’t remember I told you about that analysis initially. I’d been one of the reviewers and had previously asked to do the analysis (you may recall all that) – but it was way beyond my capabilities. Wheatley’s analysis is brilliant, He followed it up with a brilliant analysis of CO2 emissions avoided by wind and CO2 abatement effectiveness in the Australian National Energy Market (NEM) for calendar year 2014:

        The Australian study is a substantial improvement on the Irish study because whereas Ireland can be dealt with as one region, Australia had to be analysed as five separate regions connected by interconnectors. The effect of the interconnectors on emissions avoided is important. He showed that wind power in South Australia was largely being backed up by black coal in NSW rather than by higher emissions intensity brown coal power stations in Victoria (and by OCGT gas of course and by hydro although hydro only delays the timing of the emissions). Furthermore, whereas Ireland has trivial hydro and pumped storage, the delaying effect of when emissions are avoided by hydro had to be analysed in Australia. Very interesting study.

        In case anyone is interested, here is a short op-ed (by me) explaining the economic consequences of CO2 abatement effectiveness:
        What’s the cost of CO2 emissions abatement with wind turbines

      • PhilH says:

        Euan looked into this impairment of fossil-fuel generation efficiency for the UK a while back:
        and concluded: “There is absolutely no evidence from these numbers that the efficiency of large coal and CCGT plant is being impaired through cycling to balance the increasing load from wind and solar.” My analysis of the numbers for 2013 and 2014 continue to show no evidence (see Table 5.3 in DUKES 2015).

        In 2014 the UK had roughly 9% wind, 2% solar & 2% hydro generation, well into the penetration levels for renewables investigated in the Wheatley reports. So what is the UK doing right and Ireland & Australia doing wrong?

        • Peter Lang says:


          Your comment is on a different matter. It’s not about efficiency. It’s about CO2 abatement effectiveness. I’d suggest you read the Wheatley papers to understand. There are links to them here:

          • garethbeer says:

            And these Coal and Gas plants are not making money due to being pushed aside in priority with so-called renewables – the business case for then is not there! They are not selling enough Electric to be sustainable (oh the irony)!

            Hence them being shutdown, mothballed, destroyed etc. Or changed to burning North American forests – where they get double the market rate per MWh.
            There no money being made, therefore no capital to invest only 1 conventional CCGT in being built when we need 20!!!

            To ‘keep the lights on’ not only are billions been wasted subsidising useless wind and solar, now a billion is being thrown at Gas, Coal & Diesel plants in fy 19/20!

            While all this is going on, Industry is lost, industrial output is dying, productivity is crap, & jobs are going to countries that don’t run-round worry about mythical problems that don’t exist – we don’t burn witches anymore we burn jobs & wealth of the masses!

          • PhilH says:

            Peter – I think it’s a component of the overall matter.

            When I read the Wheatley papers a while ago, they seemed to be combining two components that I was interested in and one that I wasn’t.

            What I want to assess is: if 1 kWh of RE (wind, PV, etc) is put into an electricity system

            (a) what marginal fuel is being displaced – as if it’s run-of-river hydro there’s no point, at least from a CO2 / AGW point of view

            (b) how efficient the displacement is, ie for each kWh of RE, how much is the displaced marginal fuel generation’s fuel burn being reduced (DMFGFB), compared with what is normally burnt to produce 1 kWh from that marginal fuel

            (c) the Wheatley papers include in their assessment what proportion of the electricity system’s overall CO2 output is represented by the DMFGFB. But this depends on the characteristics of the rest of the system – to see what I mean, consider two simplified electricity systems:

            i) one supplied by 90% nuclear/hydro and 10% gas – introduce 1% RE to reduce the gas by 1 percentage point – this reduces the overall system CO2 by 10%

            ii) one supplied by 90% coal and 10% gas – introduce 1% RE to reduce the gas by 1 percentage point – this reduces the overall system CO2 by ~0.5%

            So there is a different overall system CO2 reduction from the same action. Worse, this number perversely appears to make it more effective to add a unit of RE to an already-low-carbon system, and less effective to a high-carbon system.

            For the case of Ireland, from the Wheatley (2013) study, it’s [see (a) above] primarily gas that is the marginal fuel being displaced (pp 2 & 12), with [(b)] a CO2 reduction efficiency of 0.28 tCO2/MWh / 0.35 tCO2/MWh = 80% that of gas.

            Euan’s analysis for the UK shows that increasing wind & PV has been displacing gas & coal burns with [(b)] 100% efficiency, whereas the Wheatley studies show that Ireland & Australia’s abatements have been significantly less than 100%. So my question remains: why is the UK’s experience so much better than that of Ireland & Australia?

          • Peter Lang says:


            You have not understood the Wheatley papers. They are empirical analyses of what actually happened’. Danniel Kaffine did similar empirical analyses for ERCOT. There have been many others. but Wheatley’s is the ‘gold standard’, IMO. You are confusing efficiency and CO2 abatement effectiveness and confusing modelling studies and studies of empirical data. There is no point discussing it until you have a good understanding of the analyses and also of the Sustainability Energy Authority of Ireland’s study in response to Wheatley’s (but covering a different geographical area and for a different year). If you are prepared to study these and others and understand them so you can correctly summarise what they say, then it might be time for a discussion, but not until then. I certainly cannot go through your long comments arguing with and correcting all your assertions here.

            Wheatley’s analyses have not been refuted and there’s been a lot of debate. So, I am fairly confident I can trust them.

  3. Graeme No.3 says:


    As you crowd turbines closer together you get interference from the turbulence generated e.g.

    Also as you search for more sites for turbines you find the best one have already been taken, so the output per turbine capacity will fall.

    • gweberbv says:


      please have a look what crowded really means:

      The average wind farm that I know looks more like that:

      I really doubt that limited space is an issue. However, due to the relatively low capacity factor of onshore wind turbines you cannot achieve high penetrations levels anyway (see me comment below). You can it compare to PV, if you like. Once you have so many solar plants installed that they can completely cover demand during the peak time in summer, it makes not much sense to build more of them. Thus, for PV capacity factor of 10%, you can conclude that the maximum achieveable penetration is of the same order.
      To get much higher, you either need waste amounts of storage capability or you need to increase the capacity factor. The latter is quite easy for wind, just go offshore. But once you go offshore, the argument of limited space obviously collapses.

      • robertok06 says:


        “I really doubt that limited space is an issue.”

        Guess what, Guenter? You are wrong on this one too!..

        “The results give roughly 1TW for the top limit of the future electrical potential of wind energy. This value is much lower than previous estimates and even lower than economic and realizable potentials published for the mid-century (e.g. DeVries et al., 2007, EEA, 2009, Zerta et al., 2008).”

        • gweberbv says:


          world electricity production is something like 2.5 TW (assuming continuous production over the year). Thus, a potential for wind of 1 TW looks not too bad in the first place.

          Moreover, it turns out that Northern Europe (and some other regions) exhibit relatively good conditions for wind:
          As a consequence, these regions can harvest a far greater share of the global wind potential than other parts of the world. Thus, it is unlikely that they will ever run of space for wind power (even if we take the 1 TW global potential from above at face value).

          A study by IWES (Institute for Wind Energy) for the Federal Environmental Agency of Germany from 2013 concludes that for onshore wind about 14% of the land could be used and if you cover this area with 3.4 MW wind turbines (being either optimized for low or heavy wind locations) that have the minimum necessary distance to each other, this enormous wind fleet would produce about 2900 TWh per year (from 1200 GW of installed capacity). Thus, Germany alone would harvest about 1/3 of of the 1 TW of continous wind power production being the worldwide potential according to the study you are referring to (if in addition we completely cover the exclusive economic zone of Germany in the North Sea with offshore wind farms, we might even reach 50%, I suppose).
          This is just to point out the variation of those studies, depending on the assumptions that are being made.
          Here is the link to the IWES study (unfortunately I found it only in German): (look at table 9 and 10 for installed capacity and production)

          Side remark: Figure 11 is very intersting because it shows how drastically the potential shrinks down when one increases the minimum distance between wind turbines and housing areas. Set this to 3 km and you will find that there is no space left for a single onshore wind turbine. Playing with such paramters allows you to produce any desired result.

          Disclaimer: By no means I am implying that Germany should build something like 1000 GW of wind power.

          • robertok06 says:



            world electricity production is something like 2.5 TW (assuming continuous production over the year). Thus, a potential for wind of 1 TW looks not too bad in the first place.”

            1) “TW” is not electricity produced, Guenter… that’s measure in TWh, eventually… you talk of energy and use units for power!… need to go back and study a bit the basics…

            2) Anyway, 1 TWe means 8760 TWh/y.. while just the European consumption is 2300 TWh/year, China’s is > 4000, same for USA… Japan 1000, India desperately increasing it… total worldwide is, if I remember well, 23000 TWh… yes, here it is:


            See… it’s a mission impossible, I told you!

          • robertok06 says:


            “A study by IWES (Institute for Wind Energy) for the Federal Environmental Agency of Germany from 2013 concludes that for onshore wind about 14% of the land could be used and if you cover this area with 3.4 MW wind turbines ”

            Guenter: nobody will ever be able to cover 14% of Germany’s land with turbibnes!… the real greens will come to the rescue and object into transforming a beautiful countryside into one of those virtual-reality video games.

            Keep the lignite power plants up and running, you’ll need them for a looooong time, I assure you… cough!… cough!… cough!…

          • Bernard Durand says:

            gweberbv, the CF of onshore wind turbines in Germany is around 0,17 on average, which means roughly 1500 GWh produced annually par MW. With 1200 GW, you produce 1800 TWh a year, not 2900. A rule of thumb is that you can install 10 MW of wind turbines/km2. Therefore 1200 GW means 120 000 km2, which is roughly 1/3 of Germany, not 14 %. If you want to produce 2900 TWh, you need 1900 GW and 190 000 km2.
            1200 GW means 400 000 turbines of 3 MW, 150 meters high including the rotor, a little bit more than 1 giant turbine/km2 of Germany on average !
            This means that nearly all Germans, except those living in big cities, would see a wall of giant wind turbines surrounding them day and night. Have the Greens fooled them so much that they would accept that ?May be will they awake one of those days? But, as said Mark Twain, it is easier to fool people than to make them recognise that they have been fooled

          • gweberbv says:


            1) Look at the manuscript that you were referring to. This guy did neither state installed capacity nor harvested energy (per year). Instead he stated an average power production – which is measured in W (or W_e as he calls it). I compared this to the average power production on the planet, which is something like 2.5 TW (agrees well with your number of 23000 TWh for one year).
            By the way: How often do you pointlessly correct your colleagues that the rest mass of the electron is NOT 511 keV, but 511 keV/c^2?

            2) Look again at your source. Mr. Castro did not discuss the socioeconomic limits of installed wind turbines. Instead he aims for an upper estimate of wind power that could be harvested if one ignores all restrictions besides pure physical constraints. From this top-down approach he ends up with 1 TWe (=8700 TWh per year). The IWES study takes a bottom-up approach and ends up with 1/3 of this number only for Germany – and using ‘only’ 14% of the space. So, the IWES study is even more restrictive with its assumptions that the Castro study.

            The point is not that nobody wants to cover 14% of Germany with wind turbines. The point is that two studies with roughly the same scope (=upper limit for wind potential) result in a huge deviation with respect to the wind potential. (I hope you care for the quality of a study independent from the fact that the result makes you feel fine.)

            However, I think it is not too complicated to get an idea where Mr. Castro probably went wrong. The assumption that only the energy dissipation in the first 200 m of the atmosphere can be used seems rather unphysical to me. What happens, if a wind turbine (or thousands of them) extracts kinetic energy from the first 200 m of atmosphere? Most probably there will be energy transfer from air moving at 201 m to air that got decellerated/distorted at 199 m, right? (Just in case you really had a deeper look into the study and did no just found the title/abstract suitable for your purposes.)

            Otherwise you would expect the first 200 m will literally become depleted in areas where a lot of wind turbines are in close vicinity. 100 TW of the first 200 meters equals to only 200 kW per km2 (surface of the world is 500 mio km2). But obviously you find several places where you can extract more than 10 times this value (and as a physicist you probably understand that this means, there is probably 100 times more power in the air as the harvesting procedure is much less than 100% efficient within this area of a km2). Whoops!

            Bernard Durand,

            you are right and wrong at the same time. Frist, you state the CF roughly correct. In reality it seems to be slightly higher (19%), see here:
            But the IWES study is not about turbines that were built, but about turbines that could be built. For example for low wind locations they are assuming ‘low wind turbines’, which basicly are huge turbines with a relatively small generator. Thus higher CF, but also higher costs. If you take the study at face value, you could scrap 99% of the existing wind farms as they are not optimized for highest output in kWh but for highest yield in €. For example, the study places a 3.4/3.5 wind turbine every 0.65 km2 (minimum distance is roughly 450 m between each other).

            But in the end it is just a study for give an upper limit for the wind potential. Yielding a value which you could simply translate into: Much more than we ever will be wanting to build. And showing how questionable the world limit given by the Castro paper (referred to by Roberto) really is.
            I doubt that Germany will ever install more than 100 GW of onshore wind. It just does not make sense, even when optimized turbines might yield a capacitiy factor of 0.25.

          • gweberbv says:


            For example, the study places a 3.4 or 3.5 MW wind turbine every 450m. This results in roughly 20 MW per km2. So 14% of Germany is roughly 1000 MW.
            And they assume a median capacity factor near 27% (using state-of-the-art onshore turbines with very large rotors).

  4. gweberbv says:

    The amount of additional interconnector capacity that is demanded by this study looks small too me. At least this aspect seems to be manageable.

    On the other hand one has to realize that the times of a national energy (electricity) policy are over in such a scheme. Too much interdependencies between the countries to allow one of them not to march in line. To me this is a good thing, not a bad one. But other people might fierceful oppose such a system.

  5. Gerard says:

    Ant thoughts on the “glut of gas” coming to Europe even without UK shale gas?

    • Euan Mearns says:

      Its too long to read. But this caught my eye:

      The price of Russian gas at the German border has dropped from around $11/mmBtu to around $6.50 in July 2015:

      The reasons for these downward trends are well known: the economic crisis in combination with competition from renewables, cheap coal and energy efficiency. (Warm weather is usually not mentioned; it would be interesting to know what the effects of climate change on European gas demand will be.)

      They may be well known but not to the author. My understanding is that Russian gas prices are linked to oil price and so the real reason is collapse in oil price. Send out 1000 rigs fracking shale oil in USA and send the Russian gas price into a tail spin – I’m sure its a coincidence.

  6. singletonengineer says:

    How right Graeme #3 is!

    I live in Australia, which is far less crowded than, for example, UK. Thus, crowding of wind turbines would at first glance appear to be less of a problem here than elsewhere, but it is only a matter of time.

    However, your second comment is spot on. Some wind apologists claim future advances in wind turbine efficiencies as though they were guaranteed and available today. These same folk have never, to my observation, allowed for the effects of future crowding of the best sites and/or of availability of only lower ranked sites as time progresses.

    Others have pointed to the limitations of various levels of penetration of wind and PV in stable networks, including studies which suggest that the maximum economically effective penetration of wind power in a network is the fleet’s nameplate rating multiplied by its average capacity factor. (

    I am yet to see pro-wind advocates include in their analysis the costs and system effects of declining capacity factor of new wind turbines due to the best sites having been already taken. If a capacity factor of, say, 30% is achievable by wind power in 2016, will the same capacity factor be achievable at a later date, when there are twice as many turbines crowding the best sites? Or will it be closer to 25%, thus reducing by one sixth the projected income for the whole national wind power fleet? I don’t know, because the available discussion papers ignore the declining attractiveness of future sites, either due to congestion, lack of wind resource, or remoteness from existing transmission line connection points and instead base their calculations on projections from the historical costs for accessing the best sites, which tend to be already occupied.

    • gweberbv says:


      even with a capacity factor of 30% which is quite good for onshore sites, you won’t have much fun once wind penetration is growing into double digits. I assume that for having wind as a major backbone of electricity production, you want to have more than 45%.

      At least in Europe this means you have to go offshore – and I mean real offshore (not just a few km away from the coastline). The first German offshore test site yielded capacity factors above 50% for several years. See here:
      But when you go offshore, you have plenty of space available with very good wind conditions.

      So, I think the problem you are discussing will not show up in reality. Once you want to build so much wind turbines that you are running out of nice onshore locations, you will be forced to put a good portion of the turbine offshore anyway. Otherwise you will not achieve high penetration levels.

      • Graeme No.3 says:


        Many of the wind farms in Australia (or say they can) operate at a CF of 30%. The one in Albany in WA is an ideal site and was claimed to be capable of 40-41% but actually achieves 31-33%.
        A few years ago a large project was announced for NSW at 25%, they couldn’t find a better site. With changes in the Government never went ahead.
        Yes, you can go off shore – but the further off-shore the more likely you are to run into bad weather. You certainly get higher construction & maintenance costs to go with the better output, but overall the output is far more expensive than the already uneconomic shore based turbines.

        There must be a limit to the amount that people are prepared and capable of paying to meet what is STILL an unproven emergency.

  7. Bernard Durand says:

    In this document, is there an analysis of the consequences of a one week wind lull at the scale of Europe ?

    • The figure showing daily wind variation based on 30 years of weather data shows that the wind turbines are sufficiently dispersed across Europe such that there isn’t a complete daily lull. There are days when 280GW of wind capacity are producing a daily average low of about 18GW (a load factor of about 6%). The data are not there to show whether this can last for more than a day or up to a week.

      • Euan Mearns says:

        I got a figure of 3% from “The Wind in Spain Blows”, EDF are close enough, its effectively zero.

      • Roger Andrews says:

        The figure showing daily wind variation based on 30 years of weather data shows that the wind turbines are sufficiently dispersed across Europe such that there isn’t a complete daily lull. There are days when 280GW of wind capacity are producing a daily average low of about 18GW (a load factor of about 6%). The data are not there to show whether this can last for more than a day or up to a week.

        Grid wind generation data are available for a number of European countries, and Energy Matters has already linked to and analyzed these data in the following posts:

        The analyses show that there are periods when the wind dies almost everywhere, and that some of them coincide with peak demand periods on winter evenings when a cold high-pressure system covers Europe (February 8, 2013 is an example). Windless periods that coincide with peak demand aren’t a serious problem at current levels of wind penetration, but at planned future levels Europe will at some point find itself in a situation where everyone runs short of power at the same time on a cold winter evening and no one has any spare power to export, whereupon interconnectors become worthless. And if there is insufficient backup power to cover the wind shortfall then the lights go out.

        • Roger: Perhaps the reasons that the EDF study does not exhibit a complete lull are that the data are daily averages rather than for just a few hours and also that there is a wider geographical spread, including Poland and Italy.

        • Euan Mearns says:

          And some of us face what may be a difficult black start that may take weeks. The more I learn, the more I am amazed at the cavalier attitude of those who govern us. I’m quite sure that none of them have a clue what they are doing.

          • Euan: I think this excerpt from the EDF report confirms what you say:

            The results of the performance of the European system integrating a high penetration of variable RES do not provide clear economic justifications for further wide-scale development of centralized storage for managing the generation-demand balance, given the volume of storage that already exists.

        • Grant says:

          The lights going out for a few hours would be a relatively minor problem.

          The heating going off for a few hours may have significant impact on some people – ditto aircon going off should the ever increasing temperatures that are predicted result in the “balancing” of electricity consumption through the year as Europe adopts air-conditioning more widely.

          A few billion computing devices going off line or crashing badly and requiring extended efforts to recover them and their data files may be a greater threat and potentially a huge cost. A truly extended disconnection could be a greater threat to business, jobs and therefore social stability (in so much as it exists) than people are prepared to consider.

          Now, large organisations will likely have, in theory, generator backup systems (typically diesel and here in the UK maybe part of the UK STOR fleet) that cut in automatically to retain supply.

          However in the 2 situations I have been aware of where backup resources of that type had been implemented for organisations I was working with at the time, both failed to work on first test. Both resulted in several hundred hours of re-work and downtime for the systems in use when the test was performed.

          Bad planning? Certainly. But both companies were at the time at the forefront of IT development and should have known better suggesting, perhaps, that either they pay less attention to internal processes and projects than to those of customers OR the whole concept is, for most people, not thought to be a “real world” issue offering great risk. Alternatively one might wonder whether such systems as as full proof as the sales teams claim when the customer is negotiating the order.

          I would not trust a project on the scale of those proposed by the EU/European governments to produce anything like a robust outcome and landowners and “Energy Companies” rush to build subsidies farms pointing to cries of “Urgency” to justify any shortcuts they can think of all the way through the process. Even if the entire plan was fully thought through and assessed by entirely competent and realistic people something would occur to damage it during the time of deployment – lack of available funds for the “energy security” part of the project should be assumed. It would not be considered an upfront need – indeed in a warming world should not be needed at all …. – and so could be allowed to slip and slip and eventually hardly happens at all. Major projects tend to be like that.

          • gweberbv says:


            if it is really the case that a lot of backup schemes based on emergency diesel (or something else) are flawed because people do not realize that in the end they may be really needed, then integrating these devices into a regulated backup scheme on a national level is a very good development.
            At least if you assume that people will take this topic much more serious when they can earn money with their backup systems and on the other hand will be fined if the systems fail a test run.

          • Euan Mearns says:

            Generating any electricity from oil is a regressive step for society. Wouldn’t have happened if oil price was still over $100.

    • Willem Post says:

      No, there is not.
      There is a post on Energy Matters which exhibits the lull situation all over western Europe.

      Example of CSP Energy Lack of Reliability in Spain: CSP w/storage is weather-dependent AND seasonal, therefore unreliable for peaking, filling-in, and balancing. The below URL shows a cloudy period in Spain reduced CSP energy production to near zero, and in winter energy production is much less than in summer. CSP w/storage in the US southwest would have a similar production profile.

      In light of the Spain experience (see URL), CSP w/storage, after 15-20 years of development, appears to be nowhere near ready for prime time. It required great cost to implement, $million/MW, (which Spain could not afford) and provides just a little of unreliable, expensive energy!!

      Example of Wind Energy Lack of Reliability in Europe: The wind energy output, MW, is less than 10% of total installed capacity over an area from northern Sweden to southern France many times each year, as shown by the published records of simultaneous hourly wind outputs. For example, during September – October 2015, 60 days, there were four deep regional lulls when the combined output of the 50 GW of installed capacity was less than 5 GW. The lowest combined output was on October 3, at 2074 MW (4.2% of capacity) and the longest lull was October 18, 19, 20, about 72 hours.

      What if that area of Europe decided to have 50% of ALL of its energy, not just electrical energy, from wind energy, per the Jacobson Plan? How much extra capacity and storage would be needed, including for peaking, filling-in and balancing? CSP with at least 10 h of storage* in the Sahara Desert (vulnerable to terrorists), and an HVDC overlay grid covering the entire area would be required (the offshore energy systems require energy, even when they are down). What would be the capacity? How much would it cost? How many years to implement?

      * 10 h of storage is understood as 10 h of “full-load” storage, or about 16 h of “60% of full-load” storage, which, in winter, would be barely sufficient for continuous operation, even if the next day has average sun, and if less than average, it would be insufficient. Energy would need to be available from other sources.

  8. Confused Mike says:

    Fascinating study and a lot to absorb.

    A couple of thoughts and it is understood that no financial assessment the Euros, Pounds and other currencies which are and will be spent even to achieve this “nirvana of EU planning”. I believe this is needed since eventually it will come back to haunt us all in power bills:


    1. I’m struggling to put into simple language for a peak demand of 600 GW we require X GW of total generating capacity divided into Solar on and offshore wind, Nuclear, Coal, CCGT and OCGT and do these figures then cover the huge weather annual variance (200 GW) quoted. A simple (?) cost per GW of each power source could then identify what is the incremental cost over the next 14 years (to 2030) to get to this presumed RES target from today’s disjointed European power portfolio even if what is there today maybe too much in calmer or less sunny countries relative to this study?

    2. I understand the presumption that the right RES has been located in the correct geographical area for wind and sun but we know that Europe is not doing this – Each country is ploughing its own furrow and hoping or expecting its neighbours to take the surpluses when a strong wind blows.
    Is there enough information to say that if , say a ten per cent larger RES generating capacity (and associated backup) than this study assumes is needed was built because new generation capacity build is not going to happen in the optimal place how much that incremental cost would be and how it compares to a cost estimate of the presumed incremental interconnector capacity assumed in this study?

    • gweberbv says:


      obviously the study took into account what renewable capacity was already installed by the various countries and then the authors put some capacity on top of that. At least, I can imagine no other reason why Germany should have 3 to 4 times more PV than France.

      • Roberto says:

        ‘At least, I can imagine no other reason why Germany should have 3 to 4 times more PV than France.’

        I can!… Just look at the % of votes to the German green parties and the French ones, at the latest elections…

  9. Dave Ward says:

    Good article, Philip. A thought has just occurred to me: How much easier would it be to run a high proportion of variable generation if the entire grid and main distribution system was DC? With high power inverters available now, the actual conversion to AC could be undertaken at local substations.

    Or even go a stage further and convert the entire grid and distribution network to DC! I know this was the typical supply in the early days of local power companies, and AC took over mainly because it enabled transformers to be used to step voltage up and down. However, now that switch mode power supplies have virtually taken over in domestic equipment, and variable frequency inverter drives are widely used in industry (both rectify the AC input to DC), the potential is there to do away with AC altogether. I know it would be prohibitively expensive to convert an existing network, but could (theoretically) a DC only grid and distribution network be constructed and operated with modern semiconductor technology?

    As to whether this technology would be as robust over the long term as traditional transformers and switching equipment is a moot point – I’m just curious if it’s feasible, and if this approach would avoid the known problems Philip has mentioned of maintaining frequency in geographically separated “Island Grids”

    • Willem post says:

      Small problem.
      The synchronous rotational inertia, which acts as a stabilizer on existing grids and connected grids, is eliminated with an all DC system.

      • Dave Ward says:

        “Is eliminated with an all DC system”

        Not entirely, as switch-mode conversion systems normally incorporate large capacitors between the primary and secondary stages. It’s primarily these which determine the short term surge capability. If (and I know it’s a BIG if…) these were large enough to provide the same amount of stabilization that is currently provided by the thousands of tons of rotating machinery in existing AC grids, would an all DC system now be feasible? Think of the new breed of portable “Inverter” generators. These don’t have to run at a fixed (frequency related) speed, but can slow down when the load is low. I don’t imagine that multi megawatt power station gensets would operate in quite the same manner, but small variations in shaft speed with changing grid loads would no longer be a problem if maintaining synchronisation was not required.

  10. stone100 says:

    What hope is there that liquid air energy storage might provide peaking capacity and storing wood pellets might provide for longer lulls in the wind? Coal power stations could be converted to wood pellet firing and then paid to sit on standby as long term energy storage rather than viewing them as active power stations. I’m no energy expert, I’m just asking as a naive outsider.

  11. garethbeer says:

    Wood pellets from where, how are they transported, how much subsidy is thrown at it, how high do bills go, how many jobs lost??

    • garethbeer says:

      Sorry Stone, bit bitey today, all Q’s I had years ago, many answered on this blog, look at old articles..
      You will find many of the memes thrown at the innocent public are simple slogans repeated enough by enough shills and useful idiots in the media – it becomes a truth, but sadly isn’t and vox pop answers are not answers at all!
      This renewable sham has cost multi-billions across uk (and world) and what has it achieved, more expensive power, old or poor people choosing heating or eating, a declining industrial base with it good jobs in decline!

      Our CO2 emissions haven’t declined they’ve been exported with the jobs! The ‘plant food’ is now in China, Vietnam, India…

      WTF – 10-15 years later we are still dependant on Gas / Coal and soon diesel plants for 90% of power!

    • stone100 says:

      Gareth, my off the cuff, ignorant, imagining was a future scenario where we had a regulated utility with a fleet of on shore and off shore windturbines that provided 30GW (averaged output over long periods) and that utility was compelled to also keep on standby 30GW of Drax style woodchip powerstations that were only used during prolonged lulls in the wind (liquid air might provide shorter term senergy storage?).
      Apparently the best that can be hoped for is a wood production of 0.5W/m^2 . Since wood can at best be converted to electricity at 30% efficiency, we’d need a wood supply of 100GW to get our 30GW of electricity. Area of UK is 2.4×10^11 m^2. So, if it was all optimal woodland that would give 120GW. Perhaps having say 25% of the UK being woodland would enable us to cover prolonged lulls in the wind. We wouldn’t be sure when a lull was going to transition into being a prolonged lull and so we would inevitably sometimes fire-up and then discover that the lull didn’t outlast our shorter term storage (eg liquid air) but the aim would be to have the woodfired electricity generators purely as a standby.
      The Drax style power stations have a capital cost per kW that is in the same ball park as the windturbines. So that standby capacity would simply double the cost of energy supply (leaving aside the storage cost for the woodpellets and other shorter term energy storage etc etc). That would be getting into the ball bark of being more competitive with Nuclear (given as $4646/kW in…/assumptions/pdf/table_8.2.pdf).
      The woodchips could come from coppice grown in the UK on what is currently sheep grazing and just as with sheep grazing it would be paid for as a support for rural communities and landowners (sheep make no sense in any other respect). Wood pellets have 4.9 kWh/kg and 650kg/m^3 so 3.2MWh/m^3. It would be 2.6 million cubic metres of storage space to store 10TWh to provide the UK 30GW electricity supply for two weeks. It’s the size of the O2 arena in London…/List_of_largest_buildings_in_the…. I haven’t found any pointers as to how much it costs to store wood pellets. They have to be kept safe from fire and from rotting. The current system is to import them continuously but the real need is for vast amounts at immediate notice once every year or so. I don’t know whether it is at all comparable but the Tescos Ireland warehouse cost 70m euros and has 1.55 million m^3…/List_of_largest_buildings_in_the…. Going by that, storage space for 10TWh of woodpellets might only cost £100m and so not dent the overall capital cost for the energy storage challenge.

      (good links on FT about woodpellets needs googling for “energy forest fuels by Guy Chazan” and “wood pellets add fuel to fire in Liverpool port expansion” to get around pay wall.)

      Really sorry if this is all stuff that has been debunked in previous stuff that I’ve missed.

      • stone100 says:

        Correction to my comment above (very sorry). My guestimate for the storage size needed failed to take into account that need 3x as much wood to get that much electrical energy. So it takes THREE O2 arena sized stores of would to give two weeks of 30GW(electric).
        I did take that into account for the land area guestimate.
        I don’t think that effects the feasibility though since that is not a big part of the overall difficulty.

        • Graeme No.3 says:

          And what happens if Germany, the USA or China decides to switch to generation to wood? And once you switch the Greens will want electric cars made compulsory.
          Coppice output would be helped by the increase in CO2 but enough to cover the demand? But you are assuming that demand won’t increase, though with the increased cost of electricity that may not be a problem.

          • stone100 says:

            I guess my hope was that 25% of UK land area would be ample to provide enough wood for our needs here (Area of UK is 2.4×10^11 m^2. So, if it was all optimal woodland that would give 120GWt). Passive House building standards might mean year round demand is no higher than summer demand (as space heating might not then be needed). Perhaps energy efficiency might match increased electrification. Electric cars and liquid air trucks might be able to use energy stored at times of low demand. I know I’m mustering as much optimism as I can. I’m also far from convinced that we shouldn’t have a lot of nuclear (as much as Sweden???) but I’m just looking for a way that renewables might possibly work in the UK.

      • gweberbv says:


        why are you considering wood? Wood pellets for electricity/heat generation are a byproduct of the processing of wood for far more valuable goods. Producing wood for the sole pupose of burning it, this is very inefficient.
        Moreover, I do not understand why we are not happy with simply using fossil fuels for backup of renewables. As long as most homes are heated by gas/oil/etc, it seems ridiculous to me to put huge efforts into eliminating the last – let’s say – 30% of fossil fuels from electricity generation.

        But to verify your numbers: German ‘biomass plants’ are currently generating 30 TWh per year from roughly 15.000 km2 of farmland. If my math is correct, this comes done to roughly 0.2 W/m2. Probably to will have a hard time to significantly improve this number (in Central Europe).

        • stone100 says:

          I was taking the 0.5W/m^2 value for short rotation coppice from . Is that a bogus value? Are the German farmers just providing that biomass as a side product or is it short rotation coppice like that? Like I say, I’m new to all of this.

          • gweberbv says:


            I am sorry. I am not a native speaker. I thought that ‘wood’ is something like that:

            The number of 0.5W/m2 under optimal conditions is not bogus. In fact, I wanted to support this number by real data from large scale biomass production already happening in Germany. As reality happens most of the time under sub-optimal conditions, the number of 0.2 W/m2 is more or less in agreement with what your are citing.

            However, I think it is useless to consider biomass as a main backbone of electricity production (or more general: a source of energy) for dense-populated industrial countries. The potential is too low and there is too much competition with other important issues regarding land usage.

        • stone100 says:

          My impression was that if we are going to move to renewables then we will need Passive House building standards which provide such stringent heat conservation that barely any (if any) heating will be needed.
          Wood from short rotation coppice is not valuable timber, it is basically just a way to gather and store solar energy with the lowest possible capital cost.

          • Euan Mearns says:

            You have 6 out of the last 20 comments on this blog. You may not realise it yet, but you are a green troll. I’m looking at your publication record and see that your specialisation is a million miles away from energy research which explains why you don’t seem to have anything to contribute to this blog apart from wasting my and everyone else’s time. I’ve put you to comment moderation which means you can still comment, but I will have to approve all comments first. Your comments will have to contain something of value to be approved.

  12. stone100 says:

    Sorry Euan, I wasn’t meaning to troll at all. Like you say I’m a molecular biologist. I know nothing about this. I’m also a Green Party member. I’ve been converted to being pro-nuclear over the past few months. I’ve done my dambdest to try and get my head around possibilities for getting off fossil fuels with and without using nuclear. I’m very willing to see them debunked if they deserve it. Even if I’m banned from commenting on here (due to my lack of expertise) I’ll still value the content you put up.

    • Euan Mearns says:

      You’re not banned, just moderated.

    • Peter Lang says:


      There are many analyses by authoritative sources, and empirical evidence, showing that a large proportion of nuclear can and in necessary to achieve large reduction of GHG emissions for electricity – e.g. 50%, 80%, 90% reduction in GHG emissions intensity. There are no valid studies I know of that demonstrate renewables can do it.

      The ERP, 2015, report shows that 31 GW of new nuclear and no new weather-dependent renewables or CCS would be the cheapest option for GB to reduce its emissions to the government’s target of 50 g/kWh by 2030.

      The emissions intensity of electricity in France was 42 g/kWh in 2014 according to RTE figures . GB could achieve this with 32 GW new nuclear and no new weather-dependent renewables or CCS.

      Nuclear has been generating 75% to 80% of France’s electricity for some 30 years. It has near the lowest emissions intensity of electricity in Europe and about 10% of Germany’s.

      The evidence is clear. You just need to do objective research, not be persuaded by irrational, ideologically-motivated, nonsense.

  13. Bernard Durand says:

    Peter, it is also interesting to note that this is also an efficient way to strongly decarbonize the entire economy, by increasing the use of decarbonised electricity in transport and house heating. France has still this capacity. This is no longer the case of Germany, for long!

    • Peter Lang says:

      it is also interesting to note that this is also an efficient way to strongly decarbonize the entire economy, by increasing the use of decarbonised electricity in transport and house heating.

      Yes, , but not just using decarbonised electricity for transport and heating, but also using it to produce unlimited liquid transport fuels from seawater. Effectively unlimited electricity and effectively unlimited transport fuels. What more could we want?

      Also see US Navy Research and Audi research. Both estimate the cost to produce pure versions of the fuels we use now (without any contaminants) at $3-$6/gallon.

  14. Bernard Durand says:

    Peter, concerning US Navy and Audi, a chemist knows how to synthetise a lot of various molecules from CO2 and H2, but for mass production, he has to consider carefully costs and energy efficiency. Energy efficiency is determinant for the quantity of energy, and therefore the size and cost of the plants which will be necessary for the processing.
    An example is given below for the gas-to-power process, which is claimed by the Greens to solve the problem of renewables intermittency!

    The Greens (Fraunhofer Institute) are claiming an efficiency of 33 % in the process renewable power-to gas-to power. This means that you need three wind turbines to produce efficiently the production of one.
    This paper shows that the efficiency would be only half of that in a really industrial process. This means a doubling of the number of wind turbines and of the occupied land, but also of the size of processing plants, to obtain the same results.
    As we say here,” l’enfer est pavé de bonnes intentions” (hell is paved with good wills)

  15. Peter Lang says:

    Bernard Durand,

    Thank you. You didn’t mention if you had followed the debate of the synfuels from sea water and the basis of the estimates of the cost of the fuel. I’d be interested if you can refer me to authoritative studies that refute the estimates.
    Here’s one analysis of the cost estimates:

    Over half the cost is for hydrogen using hydrolysis. however, High temperature nuclear reactors can be designed to produce hydrogen as well as electricity for much lower cost. The $3-6/gallon estimate could be close to halved if high temperature reactors are used. I recognise that all this is decades from being commercially viable and may never be, but it is one example of a technical solution to unlimited transport fuels produced by nuclear energy. Therefore, nuclear can potentially supply most of the world’s energy for thousands of years. We don’t have a technical constraint, just a political block to progress.

    • Peter Lang says:

      Audi diesel from CO2 and electricity

      Key points for the estimate of cost per tonne of diesel:
      • Hydrogen: $1,176 (but 50% higher for the process they assumed)
      • Electricity = $55.20
      • Thermal energy: $90.35
      • Total: $1,322 (to $2,000)
      • 1 tonne diesel – 352 gallons
      • Cost per gallon: $3.76 (to $5.43)

      These are within the range estimated by the US Navy for producing jet fuel from seawater and nuclear power on board nuclear powered aircraft carriers (i.e. $3-$6 gallon). However this is the cost of the feedstocks only. We need to add “several more dollars per gallon” for the capital cost and O&M costs of the processing plant and then distribution costs.

      For comparison, “the current spot price of diesel in the U.S. is under $2/gal.

      Points I noted and questions:

      1. The article says:

      This is also $17.25 per ton of carbon dioxide captured, which is much lower than other numbers I have seen — especially considering they are proposing to extract the carbon dioxide from air.

      1. $17.25/t cost of extracting CO2 from air is about 2% of the $1000/t cost a friend sent me a couple of years ago for my critique of this post on “CO2 sequestration in Antarctica”: . (Unless I’ve misunderstood something). The email included this:

      * A paper came out in December last year on thermodynamic limits to the energetics and the cost of direct air capture of CO2, and operational experience with industrial separation processes. While the thermodynamic limit is about 20 kJ/mol CO2 for air extraction, actual processes use around 400 kJ/mol. A cost of ~$1000 per tonne was estimated. […] The paper is here (free): . A summary is here:

      2. Natural gas is used to heat the steam. That makes it not renewable and also a CO2 emitting process.

      3. Hydrogen production comprises 90% of the total cost of synfuel production (i.e. $1,176 / $1,322). The cost estimates assume hydrogen at $4/kg ($4,000/tonne) based on an NREL report. However, estimates for the cost of hydrogen from high temperature nuclear reactors are around half the cost, e.g.:

      The economics of hydrogen production depend on the efficiency of the method used. The IS cycle coupled to a modular high temperature reactor is expected to produce hydrogen at $1.50 to $2.00 per kg.

      Therefore, using hydrogen from high temperature nuclear reactors could halve the estimated $3-$6 per gallon estimated cost of diesel and jet fuel.

      4. A point near the end of the article provides an important reality check”

      If everything works as hoped, they will then need to scale up again to something in the 100 to 1,000 barrel per day range. These scale-up steps are like gates that must be successfully passed, and historically most seemingly promising processes fail to pass through those gates for various reasons. As a result, one should never take too seriously a cost estimate for fuel production from a commercial plant when the data is derived from experiments at a much smaller scale.

      I am surprised the author didn’t consider the option of using high temperature reactors to produce the hydrogen.

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