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Published on April 7th, 2014 | by Mike Barnard


Vertical Axis Wind Turbines: Great In 1890, Also-rans In 2014

April 7th, 2014 by  

Vertical axis wind turbines (VAWT) continue to get attention, press and R&D funding. Antagonists of mainstream wind generation continually point at them as if they were a superior technology. People perpetually re-invent them and believe that they have found something new and exciting. However, they are undeserving of any significant attention, are an inferior technology and definitely aren’t new. Outside of a couple of niches, they are more of a distraction from deployment of effective utility-scale, horizontal axis wind turbines (HAWT) than anything else.

Screen Shot 2013-02-22 at 9.49.48 AMSimple drag vertical-axis wind turbines have a long history, and a version was used as the first electrical generating wind turbine ever, built by Professor James Blyth of Scotland to power his holiday home in 1887.

Even then, however, the advantages of horizontal axis wind turbines were being explored, as Poul la Cour of Denmark built the first HAWT with aerodynamic blades in 1891.


Fast forward 130 years, and there are about 300,000 utility scale HAWTs with a capacity of over 300 GW in over 100 countries around the world. There are exactly zero utility scale vertical axis wind turbines operating today, and yet the myth of their superiority persists.

Despite variances, there are really only two major types of vertical axis wind turbines:

  • Savonius-style turbines are basic drag machines. They typically have rounded paddles which catch wind in the cup and shed it on the rounded front, allowing the difference in drag to rotate the turbine. They have been around for centuries in one form or another, but Savonius got his name to stick to them in 1922.
  • Darrieus-style vertical axis wind turbines have aerodynamic blades which fly through the wind on their power strokes as they rotate around a shaft. Once again, origins of this are older than Darrieus himself, but he did create the patent in 1931.


The physics behind the superior generation capabilities of HAWTs over VAWTs is fairly explanatory with a couple of straightforward graphics.  The graphic on the left shows that HAWT blades are always flying in the cleanest air possible, and are turned to face directly into the wind. Wake eddies do not interfere with generation of the device but dissipate downwind. The blades are always flying at optimal angle to catch the force of the wind in the swept area.


VAWT blades, by comparison on the right are in their optimal angle to the wind in only a small portion of their entire span, and their blades fly through air that they have made turbulent the majority of the time. That is of course for the more efficient of the two styles of vertical axis wind generators, the Darrieus-style ones. The Savonious-style ones actually push air out of the way on the return of the paddle, even more severely limiting potential generation.


The graph below is from the 2006 book by E. Hau., Wind Turbines: Fundamentals, Technologies, Application, Economics. Springer. Germany. 2006. It shows relative potential (and actual) generation efficiencies for various types of wind generators, with three-bladed HAWTs unsurprisingly at in the most advantageous position. It’s actually a much older diagram than that, but merely an obvious statement to include in textbooks.

As you look at the devices, you can also fairly quickly see that for a given swept area, more material is required for a VAWT than a HAWT. Combined with the requirement for VAWTs to have a larger swept area to achieve the same generation, this drives up material costs as well. This reduces the economics of VAWTs further.

So given that physics, testing, economics and experience clearly show HAWTs to be the superior choice, why do VAWT proponents and others still get excited over them? Well, a lot of it has to do with a negative reaction to the dominant, mainstream technology, and myths that get spread, as well as a misunderstanding of the compromises involved in wind generation. What follows is a collection of debunkings of the most common differentiators VAWT proponents claim for their technologies.

1. Utility-scale wind farms are set up where winds are relatively stable, so catching the wind from any direction isn’t a particular advantage

Proponents claim that VAWTs catch the wind from any angle, making them more effective than HAWTs.  Catching shifting winds and eddies from any direction is only an advantage in small-scale situations such as urban or rooftop settings where the wind resource is so low and turbulent that potential generation is also heavily constrained.  Horizontal-axis wind turbines (HAWTs) are set up in areas with steady winds and the blades are above ground turbulence that causes variable eddies.  Wind testing is performed to establish the wind resource, and generally rooftops and low-to-the-ground implementations of any technology result in very poor generation potential.

Let’s take the Crissy Field Small VAWT Demonstration in The Presidio in San Francisco as a case study. The three types of vertical axis devices are tiny, with a combined peak generation of 6.8 KW, which is virtually non-existent compared to a single utility scale horizontal axis wind turbine which generally start at 1500 KW and go up to 5000 KW, 220 to 725 times the capacity. Given that they are low to the ground in substandard winds, their capacity factors will likely be lower than the typical 35% capacity factors (lower end) for modern wind turbines, more likely in the 20% maximum range given lower reliability. As such, a single utility scale wind turbine will likely generate 386 to 1,286 times more electricity annually than all five Crissy Field devices. As capacity factors for Category 1 wind resources now are in the 47% range and wind farms in the USA and Brazil are regularly experiencing 50%, it’s likely even worse.

2. HAWT masts don’t collapse due to lateral stress

Proponents and inventors claim that VAWTs produce less stress on the mast. This is engineering and economics.  There have only been a couple of instances of HAWT mast failures in the history of wind generation; the engineering is very sound. This isn’t a problem that needs a different solution.

3. Modern wind farms generate a lot more electricity more quietly

Proponents and inventors claim that VAWTs are quieter.  This is unproven actually, but the argument is that lower blade speeds results in lower noise, turning a problem into a virtue. There have only been two utility-scale VAWT farms or individual VAWTs built, a small farm of eggbeaters around 100 KW each and a massive 4 MW eggbeater in Canada. Neither lasted more than a decade in production, and no real noise measurements exist. 

HAWT refinements continue to keep noise emissions at the same level or lower despite massive increases in size. Let’s take a Vesta V47 660 KW device. It has rated noise emissions of 102 dB. Compare that to a modern wind turbine of 2.5 MW capacity, the GE Brilliant 2.5 – 120 with it’s sound rating of 106 dB. That is a perceptible increase in sound, and as a result, setbacks from homes are typically further resulting in the same noise levels. But the comparison is worth taking further. 660 KW devices typically had 20-25% capacity factors, while modern wind turbines are in the 35-50% range. Larger wind turbines are also spread further apart to avoid wake interference.  A comparison of single devices shows that the modern wind turbine generates about 5.5  to 8.5 times as much electricity in a year for a slight increase in noise emissions, but it’s wind farms that are important, not individual machines.

Screen Shot 2014-04-07 at 11.39.44 AM

Assuming a historical wind farm of one hundred 660 KW devices and typical spacing of ten diameters downwind and four diameters sidewind, this would spread over roughly five kilometres by two kilometres. A wind farm of only 16 modern GE devices would exist in the same space with perhaps 30% more generation  over a year. That’s sixteen 106 dB noise generators vs a hundred 102 dB noise generators for a significant reduction in overall noise near the wind farm, and on a per MW basis as well.

4. To generate the same electricity, VAWTs would have to be as tall as HAWTs, so visual impact will be virtually identical

quiet-revolution-qr5-wind-turbine-537x309Proponents and inventors claim that VAWTs have lower visual impact. This is only true for smaller wind generators, closer to the ground, which would be true for smaller HAWTs as well. This is trading off making it less conspicuous for making it less productive which isn’t particularly useful.  To make them economic for grid-scale generation, they would have to be so big that they would still be very, very visible.  As pointed out earlier, they would required a larger swept area to achieve equal generation. VAWTs only really lower visual impact in some cases as some designs are sculptural objects that happen to move, but this is also a very subjective point.

5. Shadow flicker is only a problem at dawn or dusk for few minutes a handful of weeks out of the year for any given home near a wind farm

Screen Shot 2013-02-23 at 12.04.30 PMProponents and inventors claim that VAWTs don’t generate shadow flicker that is problematic, as that is a factor of the triblade design.  Shadow flicker is a vastly over-stated concern. It will only occur for a few minutes at sunrise or sunset for a week or two twice a year at some residences near wind farms. HAWT rotation is too slow to cause epileptic seizures (and there are design studies and standards to ensure that this is true). Wind farms typically try to assess their impact on local dwellings and adjust where possible, and all three major wind farm siting tools —   WindPro, WindFarm and Windfarmer — includes shadow flicker modelling. Anti-wind advocates drum it up, but you pretty much have to be looking for things to hate about wind turbines to think it’s a problem.  VAWTs sufficient in scale to generate utility levels of electricity will still be hated by NIMBYs.

6. If all fossil fuel generation were replaced with HAWT wind farms, million fewer birds would die annually

main-qimg-976937782630ddd5b139a1b1cfd8057fProponents and inventors claim that VAWTs will kill fewer birds than HAWTs.  As HAWT bird mortality rates are typically vastly overstated and are much less than fossil fuel generation, lighted windows, cats, transmission lines, cars and many other sources of avian mortality, this is a straw man argument.  As VAWTs scaled up for utility generation capacity have not been assessed for avian mortality, it’s a straw man argument without merit, similar to the noise problem. The table below is from just one of the cross-generation form studies of wildlife impacts, this one from New York State. It points out that of the major utility-scale forms of generation, wind energy is better than most existing forms in virtually every category for birds and other wildlife.

For context, in the USA roughly one in 86,000 birds are killed annually by wind turbines.

New research is interesting, not promising

fishscalevawtarrays-5Jon Dabiri is the only researcher finding new and interesting things with VAWTs today, as he assesses interactions of more closely spaced VAWTs to see if fish schooling vortex studies apply to Darrieus-style wind turbines. He has so far found that his theory of putting counter-rotating VAWTs in more closely spaced arrays is resulting in greater generation than they would be projected to have by themselves or in more widely space arrays. However, based on a flawed underlying assumption of 100% use of land by mainstream wind farms, he’s vastly  overstating the significance of his findings. His work might result in new areas where it is economical to put arrays of VAWTs, but it is very unlikely to disrupt the mainstream wind industry.

Offshore wind generation has recently been raised as the new hope for a niche for large scale wind turbines, however assessment of all of the efforts in this space recently found only stalled research projects and small scale prototypes for remote site generation needs.

In summary, vertical axis wind turbines are historically interesting, but irrelevant to utility-scale generation and insignificant as a wedge against global warming. Continued attention to them merely distracts from the much more useful effort of deploying horizontal axis wind turbines, and is used as a wedge by anti-wind campaigners.

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About the Author

is Senior Fellow -- Wind, with the Energy and Policy Institute. He has been a deeply interested observer of energy systems for three decades. His work as a business and technical architect on large initiatives in a variety of domains gives him the systems thinking perspective and stakeholder analysis skills to engage effectively with an area as complex as the grid. He’s regularly asked to peer-review academic and non-academic publications related to wind energy by journals, organizations and individuals. Through the Energy & Policy Institute,, his blog and other venues, he focuses on bringing data-centric reality to bear in policy, siting and social license discussions related to wind around the world.

  • Al C

    Excellent, specific analysis by you Mike. I am interested in your thoughts of this new “galloping gurdie” type of technology developed by a Spanish company and reported by the Guardian on June 15, 2015.

    Can bladeless wind turbines mute opposition?

    A more efficient and less intrusive wind turbine design has been welcomed by two of the UK industry’s biggest critics and government regulators.The RSPB and the Campaign to Protect Rural England said the new turbine had the potential to open up more urban environments to the sector. Photograph: Vortex Bladeless

    A new bladeless wind turbine that promises to be more efficient, less visually intrusive, and safer for birdlife than conventional turbines has been welcomed by two of the UK wind energy industry’s most vocal critics.

    The RSPB and the Campaign to Protect Rural England (CPRE), which have both expressed concerns over the impacts of industrial-scale windfarms on the landscape and wildlife, said the new turbine was encouraging news for birds and had the potential to open up more urban environments to the sector.

    The streamlined design contains no contacting moving parts, making it virtually noiseless and less prone to vibration. Vortex Bladeless, the turbine’s Spanish developers, hopes these advantages could finally help usher in a viable consumer wind power market.

    “Wind turbines now are too noisy for people’s backyard,” says David Suriol, who co-founded the company with Raul Martin and the turbine’s inventor, David Yáñez. “We want to bring wind power generation to people’s houses like solar power.”

    Using the scientific principles of natural frequency and vorticity, the turbine oscillates in swirling air caused by the wind bypassing the mast, and then builds exponentially as it reaches the structure’s natural resonance. It’s a powerful effect that famously caused the collapse of the Tacoma Narrows Bridge in 1940, footage of which inspired Yáñez to try to build a structure to harness this energy rather than prevent it.

    “The best wind turbine will collect around 50% of energy from the wind,” says Suriol. “We are close to 40% with bladeless turbines in our wind tunnel laboratory.”

    The turbine “floats” on magnets, which as well as significantly amplifying the oscillation, also eliminates any friction and the need for expensive lubricating oils or mechanical parts. So even if newer conventional turbines are promising greater and greater power generation, Vortex Bladeless claims that the efficiency of their design will always make it cheaper at whatever scale.

    “We are using less parts so manufacturing costs will be 53% less, and the operational costs – including maintenance, land rental and administration – will be 51% cheaper,” predicts Suriol for a planned 150-metre tall, one-megawatt bladeless turbine, compared to current onshore windfarm’s most common three-bladed turbines. “We estimate that it will be 40% less expensive than conventional wind turbines per megawatt of generation.” The bladeless wind generator promises a more efficient, cost-effective and environmental friendly way to produce energy.

    This industrial-sized turbine is at least four years away from reality, Suriol confesses, but within 18 months he hopes to sell a three-metre-high version, generating 100W, paired with a 125W solar panel and small battery. This, he says, could be offered as a “really cheap system” for people living off-grid in Africa and India, supplying enough electricity for three lights, a TV and a refrigerator.

    A 13-metre, 4kW turbine for domestic use is planned within a similar timeframe, which would fall foul of current residential planning permission rules in England that stipulate free-standing turbines can be no higher than 11.1 metres high. Even if these issues couldn’t be surmounted, Suriol argues that the 13-metre turbines could be used en masse as viable alternatives to current windfarms.

    “You can put four, five or six 4kW turbines in the space of one conventional turbine, which need 5 metre diameter space around them,” he says. In fact, wind tunnel tests have shown they perform even better placed closer together as they benefit from the vortices each of them creates.

    But of most interest to conservationists is the elimination of standard wind turbine issues of noise disturbance, shadow flicker and bird strike, and the new design is arguably less visually intrusive.

    “Any development in the countryside needs proper scrutiny to ensure it doesn’t damage the environment in any way, but if [this] technology helps lower greenhouse gas emissions and doesn’t cause harm to birds, then fantastic,” says Grahame Madge, senior media officer at the RSPB.

    Nick Clack, senior energy campaigner at CPRE, agrees. “If the claims can be verified about the impacts of this new bladeless wind turbine – on carbon, the surrounding area, and cost – then it could play a really useful part in our energy mix,” he says, adding that any proposed project would still need to be properly scrutinised to reduce impact on the landscape as much as possible.

    The Department of Energy and Climate Change, whose new minister Amber Rudd recently pledged to remove subsidies for large onshore windfarms and delegate future planning decisions on them to local councils in consultation with residents, couldn’t say whether the new bladeless turbines would be exempt from such measures. But the government quango responsible for approving English windfarm developments, Natural England, said, “We could only comment on the potential landscape impact of these designs once we see where and how they would operate in any given location. However, by avoiding the use of blades, this design clearly has the potential to reduce the impact on birds.”

    With the support, among others, of Harvard University, advisers from US solar power giant SunEdison, and international design consultancy IDEO, Vortex Bladeless hopes to raise more money from venture capitalists to develop its turbines further before approaching any major energy companies to roll out for commercial generation.

    “Lots of people from around the world are supporting us, which is amazing, so we just have to work hard to do what we have to do,” says Suriol.

    • Bob_Wallace

      “If the claims can be verified about the impacts of this new bladeless wind turbine – on carbon, the surrounding area, and cost – then it could play a really useful part in our energy mix,”

      You see any performance data for the bladeless?

      “Vortex Bladeless hopes to raise more money from venture capitalists to develop its turbines further before approaching any major energy companies to roll out for commercial generation.”

      If Vortex Bladeless had the data that demonstrated that their device produced electricity at a competitive price venture capitalists would be knocking down their door. This smells more to me like someone who has an idea that doesn’t quite work and they want the public to donate some money so that they can keep playing around with things.

      It’s like the solar roadways. A far fetched idea with no solid engineering underpinnings that suggest they’re on to something. But if they can get enough people to give them some money they can keep tinkering while paying themselves a salary.

  • Helmuth G.

    Mike, I’m a little late to join the conversation, but I stumbled just today upon your excellent article. However, there is one passage I’m not clear with, and it regards the “rated noise emissions”. The figures you show for the Vesta and GE at 102 dB and 106 dB must reflect the mathematical noise concentrated at a given point in the center of the rotor, which is purely “mathematical” , but at no point, not even on the nacelle, you will be able to measure such a high value. I have measured the noise of a Leitwind LTW101 3MW turbine at 100m and 300m distances, and was measuring 56 dB at 100m, and 44 dB at the 300m distance. Now, the Leitwind is similar to the Enercon turbine equipped with direct drive, so they might be a little quieter overall when compared to turbines with gear, but nevertheless I don’t buy the 100+ dB, unless the “rating” is made the way I described before, which is purely hypothetical, and has nothing to do with reality – I mean, who is getting up to hub height to listen to the sound of a wind turbine ? 😉

  • Robert_13

    This discussion assumes large-scale industrial wind generation Small residential situations in low wind areas where HAWTs fail to pay for themselves are the only situations in which VAWTs start to make sense, but they do. They can start in extremely low winds, are self-starting and self-regulating, They produce high torque at low rpm. Some designs are more efficient in those situations that this article seems to imply, especially with well-designed air-core axial permanent magnet alternators using rare earth magnets that can generate power at very low rpm with the high torque the most effective VAWTs can produce. VAWTs are considerably less expensive all around as well. That matters.

  • Peter Gray

    Mike, I like the perspective you give with the “1 in 86,000″ birds fatality statistic. Even that might be high if we consider the future, with less deadly designs dominating. However, opponents could take justified issue if the fatality rate for certain raptors or endangered species is a lot higher than 1/86k. A little more detail could help if it’s available.

    A few years ago we took a tour of a local windfarm, and were told something along the lines that our car was more likely to kill a bird during the 40-mile round trip to the site, than the whole wind farm was during the same amount of time. I don’t remember the details, and I have no reason to doubt the claim. That was another nice way of putting this impact in perspective.

    • Mike Barnard

      The context is linked above to a full post on the subject I maintain but to bring it out, the median number for avian mortality in the USA is 234,000 annually per a big report a few months ago. Other sources out avian total population. At 20 billion after nesting (and 10 billion at the lowest point in the annual cycle.)

      That’s why we have to talk about specific species in specific sites when we talk about wind farms and birds, otherwise it’s meaningless. Altamont Pass and golden eagles is an excellent cautionary study of what not to do originally and the amazing progress over the past couple of decades in reducing mortality of that — not endangered — species. We also have to focus on endangered vs non-endangered species, mitigations and comparative harm from inaction causing continued global warming and habitat destruction from fossil fuels.

      • Peter Gray

        I agree. The first step should be to make reasonably good estimates of the value of damages from using each resource. Second step is to pay for the harm as we produce or consume the energy (it doesn’t matter which). If we did that for fossil fuels, most of the other issues would take care of themselves, and the elaborate workarounds would be unnecessary. That includes subsidies for renewables, which promote excessive consumption just as the direct and indirect subsidies for fossil fuels do.

        • Mike Barnard

          Here’s the link to my avian mortality material for reference:

          Here’s a deep dive I did on BS being spreading about whooping cranes I did as well, for specific analysis:

          And here’s a back and forth set of judgment and set of data about a very specific location in Ontario, which after all found that no bird species was in any way at risk, but that a turtle could be. It’s not a done deal yet with more court action under way:

          I disagree about subsidies for renewables by the way. All jurisdictions in the world are seeing rising consumer electricity prices. The states with the most wind energy in the USA are merely seeing the most slowly rising energy prices, similar to Australia. The merit order effect is reducing wholesale prices of electricity on average, but utilities selling the electricity onward are only passing this on as lower increases not as decreases.

          Economics will tell you that increased consumption is not linked to higher prices except for luxury outliers, not for utilities such as electricity.

          You can certainly point at gas consumption subsidies that exist in jurisdictions around the world as a problem, but not at renewables incentives such as the PTC I think.

          I write about that more fully — although it’s not the primary point of the article — here:

          • Peter Gray

            To clarify, I did not say or imply that higher prices will increase consumption. Just the opposite: all subsidies tend to reduce prices and increase consumption. I think we agree that the biggest subsidy of all is the implicit one for fossil fuels, where we do not pay for the (esp. future) enviro damage as part of the price. Eliminating that, say with a $15-30/tonne carbon tax, would be the equivalent of a higher subsidy for wind than we’ve ever seen, even if we taxed wind with a couple cents/MWh for the birds and turtles.

            So yes, given a broad failure to tax carbon, subsidizing renewables is an inefficient, second-best solution. Possibly a distant second. I don’t advocate eliminating renewables’ subsidies before the others are properly priced. If/when that happens, I can’t think of a good reason (e.g., infant industry or positive externalities) for continuing them.

          • Mike Barnard

            Apologies if I implied that’s what you believed or said. Not the case.

            My larger point is that the PTC in the USA, FIT in Ontario, Germany etc and RET in Australia do not lower consumer electricity prices, and as such do not cause increased consumption, unlike fossil fuel consumption subsidies in many countries. The incentives are indirect and only passed on to consumers as lower increases in consumer electricity prices.

            I agree that all fossil fuel incentives — direct and indirect — should be tossed, but disagree right now that incentives for renewables should be tossed.

            The position I have is the following one:
            1. Wind energy (and solar PV) is a mature, innovative and disruptive industry
            2. The negative externalities of fossil fuel generation are so great, that wind energy (and solar PV) should be incented to displace fossil fuel generation as rapidly as possible.

            It’s likely that we are disagreeing solely on tactics. Your suggestion — which is great but very, very hard to implement — is to price fossil fuel generation with negative externalities included, in addition to eliminating any existing incentives.

            Mine is to fight the easier fight and create / sustain incentives for renewables deployment that in combination with social license and merit order effect cause rapid displacement of fossil fuel generation by renewables.

            The reason that the PTC, as one example, is used in the USA is that it’s an art of the possible solution within the political and economic context of the USA. FIT in Ontario and Germany are more directive. I’ve been having a great background conversation with European energy economists on the variances between countries and the frame for thinking about this stuff.

            All answers that lead to fewer fossil fuels and more renewables are good. The necessary compromise that leads to fastest deployment is best.

          • Peter Gray

            I’m pretty sure we have the same guiding objectives, so I hope all this is taken constructively, as intended.

            Maybe splitting hairs, but “lower increases” in price are the same to me as reducing prices (and increasing consumption) from what they would have been. The size of the incentive is what counts, not so much whether it’s direct or visible.

            If we focus on a rapidly increasing percentage of all energy attributable to renewables, we can fool ourselves if we get there by promoting more consumption of all energy. For example, it sounds great if we double wind and solar from 10% to 20% in 20 years. But it only takes a 13% growth in total energy consumption (0.6% annual growth) to overwhelm that and lead to increased CO2 emissions (ignoring nuclear for simplicity).

            I agree that pushing for a carbon tax may be quixotic, but I don’t believe even U.S. citizens are as stupid about it as they’ve been portrayed by Kochs & Co. Maybe we just need to not give up so easily, and clearly explain it to them. That seems to have worked in BC, Canada.

            I’m sure you’re right that some policies work better for some countries than for others. Have you read The Climate Casino? Nordhaus gives a very clear explanation of the strengths and weaknesses of various policies, and he concedes that some of them, despite serious inefficiencies, might be the only hope for making progress.

            I agree with your 2nd-to-last sentence, except that we should recognize “and more renewables” as one of several means to the end, not an end in itself.

          • Mike Barnard

            Your point on lower increases in consumer prices leading to greater consumption is an interesting and potentially valid one, but I haven’t seen an analysis on that point. I assume it’s a continuum with some discontinuities as will all consumer behaviour models, and more obvious with business consumption than individual consumption. As I mull on that, I see an implication I hadn’t considered, which is that a lowering of wholesale prices — the price utilities pay — could lead to a reduced likelihood of utilities spending additional dollars on efficiency and conservation programs.

            I haven’t read Climate Casino. I’ll grab that one.

            Regarding your last point, absolutely. This is solely in context of my focus and the focus of our discussion, not intended to be exclusive.

          • Peter Gray

            I think very few reporters consider those broader subtle implications. It’s certain that subsidies will weaken the desired effects; how much depends on the markets involved. And lower prices will reduce the incentives for efficiency and conservation.

            A related phenomenon that is often missed is the effect of vehicle and appliance efficiency standards. We often see projections that assume no substitution – e.g., that doubled automobile fuel efficiency will cut consumption in half, or 4x more efficient lights will reduce electricity for lighting by 3/4. But people will drive a fuel-efficient car more than they would have driven the gas hog it replaces. And I know I leave my CFLs and LEDs on more than I would have used the incandescents. I use less power than before, but not 4x less.

            Yes, Climate Casino is the best I’ve seen on climate policy, by a career expert in the field, and a great writer. He describes how and why some policies are far less effective than we might imagine, and some are even counterproductive. Highly recommended for a reasoned take on what we’re facing and how to deal with it.

          • Bob_Wallace

            That holds if previous prices have been high enough to suppress consumption.

            People get a bit too carried away with Jeavons Paradox and dropping utility bills due to more efficient bulbs and TVs. People aren’t going to go out and buy more lamps and TVs for their living rooms and run a bunch of extra just because their monthly bill is down a bit.

          • Peter Gray

            >> That holds if previous prices have been high enough to suppress consumption. <<

            That's not a meaningful statement in economics. This isn't a matter of suppressing consumption, but simply the fact that demand curves slope downward – with virtually zero documented exceptions.

            I'm well aware of the Jevons Paradox, and I did not say that energy efficiency would increase energy consumption, although that can happen if demand is elastic and/or the growth effects of cheaper energy are strong. I did say that doubling energy efficiency will reduce consumption by less than half, and I stand by that.

            In cases where people are completely unaware of any connection between efficient devices and their utility bills, I would not expect them to directly respond by going out and buying more devices or running them longer. But even then, in the aggregate, people will have a little more disposable income, and we can expect them to consume more of everything. Every good or service they purchase requires some energy to produce.

            Jevons's original observation was that big advances in efficient use of coal led to rapid, sustained growth in coal consumption. He was right about that, and the same effect has applied to oil and other energy sources. The lesson is not that we shouldn't pursue efficiency, but that we shouldn't count on it as an environmental policy. In some cases it can even be counterproductive.

            This has a decent explanation:, although they're a little sloppy in using "demand" where they should say "quantity demanded."

          • Bob_Wallace

            Whatever Peter, I’m not going to play word games with you. Been there….

          • A Real Libertarian

            Bob, Peter isn’t playing word games.

            Peter, Bob is right when he says that the Rebound effect isn’t inevitable (e.g. a lot of people start thinking about how to decrease their consumption further when they start installing more efficient appliances).

          • Bob_Wallace


          • Peter Gray

            Right. I’ve been here too, where when someone disagrees with you, even a little, you dismiss everything they say as word games or something similar. That’s up to you, but it doesn’t amount to a credible argument.

            I described something that actually happens in the real world, that we might want to keep in mind when we advocate policies. Not a word game. Real consequences.

          • A Real Libertarian

            Sorry about that, but Bob’s dealt with a lot of people who attempt to cover up their lack of knowledge with jargon. (e.g. Pretty much anybody promoting liquid fluoride thorium reactors).

            He’s on a bit of a hair-trigger about that.

            I think what you were saying is that energy efficiency doesn’t lower total use as much as per-unit use? (i.e. An X using 80% less electricity only results in 70% less electricity use do to being used more often).

            Because there is evidence of countries using less electricity because of efficiency:


          • Peter Gray

            I can’t remember promoting thorium reactors, but I’ll watch out for that, thanks.
            All I’m saying is that when we double energy efficiency, for example, the common expectation is that energy consumption will go to half of what it was before, because we can get the same services with half the energy. But that doesn’t happen, because higher efficiency means the prices of those products or services falls, so people buy more of them.

          • A Real Libertarian

            “I can’t remember promoting thorium reactors, but I’ll watch out for that, thanks.”

            You didn’t but others did.

            All I’m saying is that when we double energy efficiency, for example, the common expectation is that energy consumption will go to half of what it was before, because we can get the same services with half the energy. But that doesn’t happen, because higher efficiency means the prices of those products or services falls, so people buy more of them.

            But energy consumption stills goes down, just not to half of what it was before, right?

          • Peter Gray

            >> But energy consumption stills goes down, just not to half of what it was before, right? <<

            No, not necessarily. It depends on demand elasticity in the particular markets, and on the economic growth effects of the higher efficiency. Over the past two centuries, isn't it clear that we've made spectacular efficiency gains, but per-capita energy consumption has also increased? Not uniformly everywhere: U.S. consumption leveled off and even decreased slightly since the oil price shocks of the 1970s. We've also shifted a lot of uncounted energy consumption in the form of manufacturing in Asia so even that decrease might be illusory.

            You can see the effects of policy by comparing the U.S., Canada, Australia, and some OPEC countries to Europe, where most countries imposed stiff taxes on oil long ago.

          • A Real Libertarian

            That’s from 2003.

            I mean nowadays, because it’s only been about the past decade that humanity has gotten serious about energy efficiency.

          • Peter Gray

            That’s really not true. People have been finding more efficient ways to use energy for at least a couple centuries. And if anything, the U.S. has gotten less serious in the past decade, with the Rs in control of policy.

          • Peter Gray

            One more note about that. There are good reasons to conclude that a combination of efficiency-promoting policies or mandates, along with policies that keep energy prices high, can unambiguously reduce energy consumption without reducing the quality of life.
            As I mentioned elsewhere, efficiency mandates or subsidies can be a good thing, but relying on them as our main or only policy, just because it’s more popular and politically feasiblo, is likely a big mistake. The U.S. temptation or pattern has been to do just that.

          • A Real Libertarian

            “As I mentioned elsewhere, efficiency mandates or subsidies can be a good thing, but relying on them as our main or only policy, just because it’s more popular and politically feasiblo, is likely a big mistake.”

            I thought you meant subsides of any kind (e.g. wind PTC, solar ITC, etc.) are bad and should not be supported even if carbon taxes aren’t in place.

          • Peter Gray

            Here are what I see as the bedrock principles of ideal, rational economic policy:

            1) Under ideal conditions of perfect competition, full information, and rational participants, voluntary transactions (of all kinds, not just explicit trades) in a free market will lead to efficient allocation of resources (review “efficient” in econ terms if you’re not familiar).

            2) When those conditions are not met, we have various forms of market failure; most often externalities, sometimes market power (oligopoly, monopoly, monopsony) or failure to make apparently rational investments in, say, insulation.

            3) Market failure, broadly considered, is the main if not the only good justification for government involvement in human activities. But it’s a very big deal. We could even include the legal system, contract law, regulations and standards, R&D, etc. under the same umbrella.

            4) Usually the most efficient way to deal with negative externalities is to tax the activity most closely tied to the externality, at a rate equal to the marginal external cost. Same calculation for subsidies on positive externalities.

            This means that in the ideal “first best” case, nothing that does not create positive externalities should be subsidized. This includes renewable energy, unless someone can demonstrate + externalities that they produce. Offsetting the negative externalities from a competing activity is similar, but it’s NOT the same thing.

            That brings us to consider a “second best”
            solution, where for some reason we’ve failed to tax an activity with negative externalities. Failing to tax carbon
            means we’re over-consuming coal, oil, and gas, and therefore energy in total. Adding a subsidy for wind and solar makes that market distortion worse. Part of the increased renewable consumption will take the form of reduced carbon burning, but not all of it. So in this case I’m not saying that subsidies for renewables are “bad,” only that they’re less effective than dealing with the real problem directly – maybe a lot less effective, and more wasteful.

          • Peter Gray

            I skimmed your Energy & Policy article, and you’re certainly right about the profit motive being virtually the entire driver of the anti-renewables and climate denial campaigns in the USA. I teach university economics, and one of the first principles I try to get across to students is that we can assume for-profit firms are _only_ motivated to maximize profit. For most publicly held corporations, it would even be illegal for them not to.

            For an eye-opening perspective on that, I would review the history of leaded fuel and paint. The health and social consequences of that are staggering, widely unknown, and for the sake of a relatively tiny industry. A book from 3 years ago, Merchants of Doubt: How a Handful of Scientists Obscured the Truth on Issues from Tobacco Smoke to Global Warming, is another one you might want to read.

          • Mike Barnard

            Yes, I’ve dived into MoD. I deal with Prof Simon Chapman, one of the leading lights of the global public health fight on tobacco regularly, as he’s now focussing part of his prodigious attention on the wind energy health scares front (something I’ve delved into tremendously). And of course the think tank I’m Senior Fellow – Wind with has a significant focus on unmasking the linkages between fossil fuel generation and libertarian ideologies with anti-renewables and global warming denial lobbying and PR work.

          • Peter Gray

            I’ve followed and enjoyed several of your debunking articles about concocted wind energy health scares. That kind of thing is generally a thankless task, but I much appreciate it.
            There’s an even goofier campaign against smart electric meters, which surprisingly seems to have gained traction in Australia, but not in the USA. All part of the same anti-science package, along with creationism, dangerous anti-vaccine fantasies, anti-GMO, etc.. Sad and scary that we haven’t been able to jettison all that by 2014.

          • Mike Barnard

            Yup. WiFi is a big thing in the UK.

            What’s sad is that a relatively tiny number of people can have an inordinate impact on millions or billions of people by playing on irrational fears due to the power of the technology available now.

            What’s good is that there is lots of work being done to figure out how to best use that same technology to effectively communicate reality to the same people susceptible to irrational fears. Early days, but hopeful.

          • Peter Gray

            I have the same mixed feelings about communication technology. On one hand it seems to expand the Fox News echo chamber effect, but on the other, for those (I hope many) who are willing to think, learn, and challenge their preconceptions, discussion forums like this are a good way to expose the bunk and make some progress.

            Regardless of technology, some folks are likely to be impervious to logic and evidence for the foreseeable future. Probably not much we can do about that. Or need to if there aren’t too many of them.

          • Mike Barnard

            PS: if you send me your email address at, I think you would find the discussions I’ve been having with Craig Morris, Toby Couture and Michael Hoexter of interest as you are much deeper into economics than I am. The divergence between European perspectives and US/Australian dialog on energy economics is refreshing and challenging.

          • Bob_Wallace

            I think there’s another significant component or two in the anti-renewable push.

            Part of it is a general dislike of anything “hippie” by a portion of the population. Some people have put themselves into a position of opposing anything that hints at environmentalism and have developed a hate of “pointy headed intellectuals”.

            And part of it is a basic characteristic of conservative people – they do not like change. If coal was good enough for Granddaddy, coal is good enough for me.

          • Peter Gray

            And the competing industries are hardly shy about playing on and magnifying those prejudices and fears.

  • Dave2020

    It’s nothing but cognitive dissonance when experts like Barnard put hubris above the need to re-examine their arguments. He fails the logic test even on the simple issue of bird strike. The fact that the problem is repeatedly over-stated is irrelevant. The question is – “Do birds avoid colliding with VAWTs?” If the answer is ‘yes’ – end of argument.

    He correctly points out that HAWTs are more efficient at energy capture/conversion. So what? That isn’t the problem now and it will be even less so in the future. We need to cheaply supply renewable electricity efficiently at the right time. That’s a whole-system issue.
    “The DECC, along with representatives from the industry itself, have set out scenarios enabling deployment of 8-15GW by 2020, and up to 41GW by 2030.” That’s far too much. The UK system won’t work with that penetration of variable wind power. It will often have no market.

    Worse still in Dec. 2012, “George Osborne announced huge tax breaks for the new ‘unconventional gas industries’, to ensure taxpayers fund much of their infrastructure and exploration costs, and, at the same time announced his approval for 30 new gas power plants, which will make the UK the most gas dependent country in the world.” In a UK grid made up of nuclear plus renewables, gas plants will have no market for their electricity, 90% of the year! Truly, the lunatics have taken over the asylum.

    For very simple engineering reasons, when you take marine renewables as a whole, with floating wind/wave and energy storage in particular, offshore VAWTs are fit for that particular purpose. HAWTs aren’t.

    If you exclude disruptive innovation as Mike does, for no good reason, then – “Alpha Ventus may be as good as it will ever get.” and that’s not good enough for a sustainable Green Revolution.
    See Siemens’ graphic – “How Offshore Wind Measures Up.”
    The fact of the matter is, it doesn’t measure up and it never will, with these designs as they stand. (expensively driven into the sea bed.)

    Barnard does us all a gross disservice by clinging to his conviction that there’s no alternative.

    • Mike Barnard

      HAWTS are the disruptive tech along with photovoltaic solar. They are reducing fossil fuel generation profits worldwide, innovating business models and causing utilities to drastically revise their approaches. They consistently outstrip IEA forecasts. And they are giving a subset of people such as Dave conniptions.

      No need to look for disrupters when they are right in plain sight.

      • Dave2020

        I have no conniptions whatever. It is of zero consequence to me that guys like you refuse to entertain the potentially transformative nature of a sensible level of energy storage. That is the truly disruptive technology. Billions of people may have cause to reflect “Why on Earth didn’t people like Barnard see that?”

        HAWTs are pretty much mature. That’s the basis of your case. You can’t contemplate the possibility that the industry standard has flaws. Why is that?

        • Mike Barnard

          Dave seems to be having an argument with someone else, about something else. There is nothing in this article or other articles on CleanTechnica for that matter written by me about energy storage. I’ve written about it briefly on Quora and in a couple of other places simply as something which is overstated as a need, and better supplied via grid interconnections and passive rather than active storage.

          However, that’s not what I was talking about above, in my response to Dave, or in the links in the article or in the link in my comment.

          Further, he’s then extended this complete non-sequitor with another straw man, that I consider HAWTs to be without flaws of any kind. How odd. The material on avian mortality is clear that wind turbines kill birds, just fewer than any other form of generation. This is a comparative harm vs benefit statement. As this continuing story around Ostrander Point shows, I’m clear on the need to protect endangered species where there would be impacts that couldn’t be mitigated.

          And if I truly considered HAWTs to be perfect, I likely wouldn’t continually address them in context of a very mixed set of generation sources, with likely limits on total generation capability.

          Since he can’t seem to argue usefully with what I actually say, I guess he has to make stuff up, put it in my mouth and then win arguments that way.

          I prefer to actually deal with what people actually say and do, personally.

          • Dave2020

            “There is nothing in this article . . . about energy storage.” My point exactly. I was drawing attention to that omission! It has a crucial bearing on the future design of wind power, I think.

            “something which is overstated as a need.” Maybe so, but perhaps you should review your stated position? You seem to be very reluctant to do that – closed mind?

            Nobody’s gonna win a debate by making stuff up. You think I’m making stuff up?

            You put across this very plausible point that R&D you don’t approve of is a waste of time and money. I wonder, do you approve of this:-

            “This ring is packed with 648 22cm-long neodymium magnets laced with another rare-earth element, dysprosium, which makes them much less liable to become demagnetised.” That’s not progress, even if you’re convinced that it is. Disruptive innovation would do away with the ‘generator-driven-directly-by-the-turbine’ altogether. It wasn’t mentioned above, so I shouldn’t bring it up? Is that how it works?

          • Mike Barnard

            So if I understand Dave’s argument, an article about comparative technologies didn’t mention a technology that was in the same very general space, so this is an omission.

            Let’s see what other technologies I didn’t mention: nuclear, coal, long-distance transmission lines, SCADA, fracking, hydro, smart meters, autonomous grid-balancing distribution points from GE, wind resource projection simulations such as Anemos, distribution grid tie-ins for smaller scale wind project, etc, etc, etc, etc, etc, etc.

            That Dave thinks one specific relative minor player is missing indicates that he’s got an obsession with that technology, not that its an omission in this article.

            To be clear, it’s as if I wrote an article about tank warfare tactics in Africa in World War II, and Dave took me to task for not mentioning asymmetrical warfare in Afghanistan. Yes, the two are related thematically, but there is zero need to talk about one when talking specifically about the other.

            VAWTs are a dead end outside of minor niches where aesthetics or Dabiri’s results gives them a value proposition. The comparison is to HAWTs. Storage doesn’t enter into this discussion.

            Or perhaps Dave just is an adherent that wind energy requires storage to penetrate grids to major levels, although his response indicates that he didn’t bother to follow the links to find out what I actually said. If that’s the case, he’s just wrong. I’ve provide links to my writing on storage specifically. Here’s some of what I maintain on backup in more general terms for him to ignore.

            Certainly his next statements jump to another frequent anti-wind energy myth in which he worries deeply about the same materials that are in the computer he is typing on, probably the smart phone he carries and likely in the LCD or plasma TV he watches movies on at home, the bizarre belief that because wind turbines use rare earths just like a ton of other things, that makes wind turbines somehow the cause of a specific problem. I’ll leave this with the quotes he doesn’t use and likely didn’t read from the same article.

            “The neodymium exists in large abundance outside China. There are a couple of companies outside China that could keep us running for thousands of years.”

            “It turns out you can tweak the way you deal with your alloy so you need less. In today’s magnets we have 0.7% dysprosium, and in a few years it will be all gone.”

            Oops, not such a worrisome issue after all. But Dave is unlikely to admit that, just as he is unlikely to admit that non-sequitor straw men arguments are a ludicrous debating tactic.

            Dave, I’ll tell you what. Please stick to what I wrote in this article. Find flaw in that specific material. Point out where I made technical or factual errors and I will happily correct them.

            If you are unable to do that, please understand that your continued kitchen sink of arguments is merely indicative that you are in opposition to one of the best two forms of large scale generation of electricity we have available to us, a form that needs to be built out around the world as part of the fight against global warming, a form which will reduce unnecessary deaths and disease due to pollution and global warming, and a form which is economically viable. In other words, you are part of the problem, not part of the solution and should consider getting out of the way.

          • Dave2020

            You don’t understand my argument. That’s plain to see.

            You lump me together with “critics of wind energy” who claim “that it requires complete backup” and from that false assumption conclude that I’m “an adherent” who is “obsessed” by one “anti-wind energy myth” or another. Nothing could be further from the truth. You wilfully misrepresent everything I write, because it differs in minor respects from your conventional view.

            “you are in opposition to one of the best two forms of large scale generation of electricity we have available to us, a form that needs to be built out around the world as part of the fight against global warming.” Nothing could be further from the truth. You wouldn’t make such a risible statement, if you got off your high horse and allowed reason to rule your evaluation instead of blind prejudice. Radical innovation can roll out wind, wave and/or tidal around the world that would have a far superior performance, due to dispatchability, so it could serve mega cities and remote communities at many more locations than conventional kit does.

            My proposals are founded on the benefits that accrue from NOT installing an over-capacity. Trawl through any studies you like and show me one that doesn’t predict a future of over-capacity. Several European grids have already reached that point, and interconnectors won’t deliver a cheap solution. Even a modest amount of energy storage would cut that waste significantly. (both capital and operations’ costs) My argument has nothing to do with ‘back-up’. You suggest that off-shore wind may not be “economically viable” and RWE would agree with you. My designs make marine renewables “economically viable”. (most probably)

            “Please stick to what I wrote in this article.” Just to please you? So you don’t have to engage with any dissonant ideas? Why do you feel so uncomfortable about that? It’s the scientific method.

          • Bob_Wallace

            Dave, you attempted to hijack the thread in order to pimp your Rube Goldberg floating VAWT/CAES/gen later idea.

            Do not do that.

            You’ve had plenty of opportunity to present your idea and no one bit. If you believe in your idea go raise some money and build a prototype. Produce data.

          • Dave2020

            Hijack? Pimp? Rube Goldberg? Give it a rest Bob. You can do better than that. You know very well that people in the industry likely concur with your views and they never will bite, so no feasibility studies. That’s more a reflection on them, than on the ideas.

            As for designs that “perform a very simple task in a complicated fashion”, the conventional kit fits that bill quite nicely. You don’t want to see that do you? Mike’s accusation of “non sequitur, straw men arguments” lowers the debate. He’s been resorting to argumentum ad hominem, as are you.

            My inability to produce the data has nothing to do with this. You know that too. Are you aiming to moderate a forum of free speech? Do not do that.

          • Bob_Wallace

            Do not attempt to hijack threads.

          • Mike Barnard

            And now you throw in tidal and wave tech that just isn’t there. And from Bob’s comments you are a serial offender with your hypothetical gizmo.

            Kitchen sink arguments by an obsessive aren’t worth debunking. Economics and geopolitics are even less worth discussing with someone stuck so far down the stack. Apologies, Dave but you have proven yourself incapable of having a useful conversation. I’m sure you are a smash at social gatherings though.

          • Dave2020

            “On one day in August 2013, £1.84m was paid to operators of 28 wind-farms in Scotland to turn off their turbines. Between 2011 and 2012, constraint payments from National Grid to wind farm operators totalled more than £34m.”

            There are plans for at least 3-4 times current wind capacity.

            Energy storage is off-topic? No, it’s just not on Mike’s radar. You can build the most efficient wind turbine known to man. It still generates no electricity when it’s turned off.

            “Government must recognise that energy storage cannot be incentivised by conventional market mechanisms.

            Read more:

    • Peter Gray

      Mike Barnard has been clearly, logically reporting the reality of what works in wind power, and what has failed – repeatedly. If he’s “clinging to his conviction” that 3-bladed HAWTs are the only way to go, then so is 99% of the thoroughly researched, highly engineered, competitive wind power industry. Politely, that strains credibility.

      >> The question is – “Do birds avoid colliding with VAWTs?” If the answer is ‘yes’ – end of argument. <<

      Huh? Even if the answer is "birds absolutely never collide with (real or imaginary) VAWTs," the argument would hardly be over. It would be just one small part of an overall cost-benefit analysis.

      I'm with Mike and Bob Wallace on this. VAWTs have been extensively explored, and they don't add up. If you can refute that by building and proving a design, then do so. Otherwise don't waste the rest of our time.

      • Dave2020

        Yes, it strains credibility. That’s the problem, but it’s not my fault.

        I did write “HAWTs are more efficient at energy capture/conversion.” didn’t I? That is NOT the issue.

        The industry needs to address EVERY issue besides that, which it is failing to do. Chief of those is economic viability. I’m not making it up. Read of the very real problems:-

        A single interconnector between Scotland and Norway is costed at £1.5bn. People assume that to be cheaper than integral storage? Not necessarily so. The PHS is yet to be built anyway.

        “urgent action needs to be taken by the Scottish government to halt the expansion of energy capacity, especially offshore wind, which would produce intermittent power for which there’d be no market. Currently UK energy policy is an almighty mess.” Doesn’t impress as a business plan, does it.

        I’m not giving you advice for the benefit of MY health, or MY bank balance, or on an ego trip. It is for your benefit. If you can’t be bothered to think about the whole-system issues I’ve raised, that’s your funeral. You may think the US won’t reach this point? Good luck with that.

        • Peter Gray

          Lack of storage or complementary energy sources might or might not become a crucial issue in transitioning to renewables. But that’s not what the article here is about. It looks to me as if you’re using this as an opportunity to shoehorn your favored technology into a place where it doesn’t belong.
          You seem to be saying one of the following:
          1) HAWTs are generating too much power, so the solution is to use less-efficient VAWTs. Or
          2) VAWTs are better suited for floating on wave or tidal generator platforms.
          I don’t care to get in a debate about something off-topic, but I don’t see how either of those makes a lot of sense. Surely the turbines don’t need to be colocated in exactly the same spot to help solve the whole-system issues. The articles about Scotland’s supposed energy crisis don’t seem to offer much support for VAWTs, either.

          • Dave2020

            Your point 1. is just being silly.

            Point 2. is getting closer to making sense, but it’s not co-location of wind and wave, it’s interdependent, total integration of both with before-generator energy storage vessels. The floating turbine won’t be stable without the wave energy converter, which also gives the vessel a shallow draft. (ergo, much cheaper installation than sea-bed fixed turbines) So yes, all three elements DO need to be included.

            The fourth factor, tidal, is part of the package where the geography is suitable. It would always be a VERY useful addition, because the energy harvest is utterly predictable. In the Bristol Channel, just South of where I live, an intelligently located barrage would save billions on flood damage from either storm surge or heavy rainfall. What’s wrong with joined-up planning?

            Wave energy comes in pulses, so you need to smooth that out before you drive the generator. Energy storage does that anyway, so ‘while you’re at it’ you may as well put your wind energy through the same (pressurised water accumulator) system. In this way, the sensible engineering option is to remove all electrical generation from the vessel, and transmit the energy in cheap steel pipes, instead of expensive high voltage cables.

            To improve the whole-system economics you need to remove the generators from the nacelles 100 metres above the waves and replace them with a variable displacement water pump at or below the surface. A very low c of g is simply sound engineering, for a floating vessel, hence a marginally less efficient VAWT is perfectly good enough (if not better) for this particular application.

            “Obviously, the electricity from these is dispatchable. (1GW from five 200MW generators, NOT 200 5MW generators!)”

            Energy storage isn’t a side issue. It’s an intrinsic factor in running renewables economically. To dismiss this as being ‘off-topic’ is quite bizarre. Mike and Bob only insist on calling it that because my ideas question their convictions. Cognitive dissonance is a very uncomfortable feeling, so they slip into personal abuse instead of debating the issues in a calm and rational manner. You don’t ‘need’ to go ‘there’, do you Peter?

            Thorium, “the history of leaded fuel and paint”, energy efficiency and communications technology are ‘on-topic’? OK. I don’t feel that my presence among 66 comments really amounts to a “hijack”!

          • Peter Gray

            You make some reasonable points about the discussion, Dave, but I’d suggest reviewing the earlier comments to see who started making it personal by accusing others of being closed-minded, defending the status quo, etc.. When you do that, don’t be surprised by the kind of reaction you saw. As an observer, I’d say Mike wasn’t being closed-minded; he was following Carl Sagan’s advice to “keep an open mind, but not so open your brain falls out.”

            Based on a wealth of available data, it makes good sense for Mike and others to be skeptical of VAWTs as anything more than a niche or decorative generator. I don’t know enough about the particular wave/tide/wind/storage issue you allude to, to argue the details. But it’s not Mike’s or Bob’s or my job to refute your idea – esp. when your documentation consists of a couple of vaguely related press accounts of a coming energy oversupply problem in Scotland, and another about rare earths. The rest is handwaving and unsupported, undisprovable assertions.

            If you have a clear statement of a problem, and a great idea for solving it, the next step is not to try defending it in a discussion forum here. It’s to build a detailed model showing how your system will work, entirely of components with known performance (so it doesn’t need to be a physical model). If you’re relying on any unproven components with higher performance than known analogs, you of course need to build working prototypes before anyone should take you seriously.

            Bob might have gone overboard with language about your hijacking the discussion to support a Rube Goldberg idea. But I agree with him that you haven’t contributed anything substantial to our understanding or appreciation of VAWTs. There’s only so much patience you can expect.

            Write a serious proposal with a clear, focused problem definition. Build a realistic model with all the inputs, outputs, environmental conditions, and capital and operating costs. Convince some investors to support a prototype system. Then you can have a whole cleantech blog page devoted to your idea. But before then, you’re better off keeping it to yourself.

          • Dave2020

            Hi Peter,

            Thank you for your thoughtful comment. Your opening remark is very reasonable, but you see, there’s history here – two years with Bob and since last year with Mike. The overarching point is it’s not even about the comparative merits of HAWTs versus VAWTs. They seek to limit the debate to that, otherwise they’d lose the argument, but wind power isn’t something working in isolation, and “understanding” VAWTs is of little relevance here. It’s about understanding the new electricity market and the technology that goes into its efficient operation.

            I have repeatedly explained all the issues and the rationale for the designs to Bob, but he wilfully misunderstands virtually every part of it, witness his dismissive description: VAWT/CAES/gen later idea! If it was CAES, why would it use a variable-displacement WATER pump?

            “gen later” makes no sense on any level. Before-generator energy storage allows you to generate any time you like, at any level you need to, in response to demand. Dispatched power could even exceed the name-plate ‘capture’ capacity, by simultaneously drawing off stored capacity. No data is required to understand the logic of that and it can all be built to proven engineering principles.

            Mike makes stuff up to excuse his character assassination – “. . he is against onshore wind turbines in the UK, obsessed about some gadget . .” As I wrote previously; “Nothing could be further from the truth.” The mountain landscape around here is dotted with (small scale) windfarms and the local opposition to a few more infuriates me. Their concerns are irrational. No turbine is proposed anywhere near residential property. I’d put one up, if the planners would let me. It would be a HAWT, because the ‘Quietrevolution’ is too expensive. Google it and judge for yourself the pros and cons, without any “obsessive” or irrational bias.

            Mike can no longer deny that there may be a role for a new VAWT with floating wind, so he pretends I’m some kind of nut with a hatred of HAWTs, even onshore. The cognitive dissonance and hubris are all too evident, same as before. It seems that nothing will ever be “clear” to either Mike or Bob.

            I tried to post this link and comment:-

            “more than £340m was paid in constraint payments to all UK electricity generators, amounting to approximately £13 per household.” With well designed kit that would drop to zero.

            You can build the most efficient (biggest?!) wind turbine known to Man. It still generates no power when it’s turned off.

            They censored it. Draw your own conclusions. It is an undeniable fact that a product with an inherent tendency to over-supply will never be attractive as an asset. “No market” isn’t some ‘off-topic’ issue of little concern to wind enthusiasts (like me). It is a fundamental problem, which every economist has to address sooner or later. All I’m saying is “sooner” is the smart option. They both ignore actual grid OPERATIONS and empirical evidence which shows that storage is a very important component of a viable electricity supply. The ‘design’ of the ‘market’ is also critical.

            “Government must recognise that energy storage cannot be incentivised by conventional market mechanisms.” Spain does not give constraint payments to wind generators. They’re not too happy about that! Nobody offers ANY incentives for the Rdd&d of energy storage. Where would I get the money from Peter? I don’t want to be better off (I’m pensioned off). I want all humanity to be better off. John Houbolt wanted Apollo to succeed. He had a well supported case – I don’t. It took over two years to get his idea (LOR) adopted. His opponents said he was an idiot. (His figures lie, he doesn’t know what he’s talking about) Any evidence I gather will be treated the same.

            The Spanish ‘market framework':- So-called free markets don’t do co-operative joined-up planning. We need all the best brains to work together to deal with AGW.


            A tidal enthusiast berated me for advocating energy storage, as he mistakenly believes it serves no purpose with (intermittent) tidal! He is anti-wind and argues that it’s a poor technology, because it ‘needs’ weeks of storage to make it work! (cognitive dissonance writ large?) This is what I call internecine competition – it is a gross disservice to the Green Revolution. My ‘whole-system’ design philosophy makes wind, wave and tidal complementary and that also reduces the whole-system energy storage capacity you require. Electricity storage can’t compete at grid scale.

            Roger Faulkner | 22 Nov 2012 4:26 pm.
            “It is not nonsense to consider multiweek storage schemes. Aggregated wind output from entire regions…such as North America or all of Europe, varies on about a three-week cycle. In current thinking, the remainder that cannot be balanced by pumped storage will have to be made up by dispatchable generators.” Naturally, “current thinking” always excludes new thinking!

            Tidal power, PHS and to a lesser degree wave, are all ‘geographically constrained’. Wind and/or solar are readily available over far more of the planet. Now compare the opposing views of two German experts. In my view they are BOTH wrong, but of course that is yet to be proven!!! Killing off debate gets us nowhere. Anybody who does that should be ashamed, not proud of themselves.

            Focussing on the remote possibility of widespread ‘low wind’, obscures the real issue, which is the inevitability of frequent widespread ‘good’ wind events, that will generate a huge over-supply.

            Nobody will profit from an over-capacity. Before-generator energy storage solves both problems, but due to the laws of physics (i.e. engineering) it’s only viable as ‘cold’ mechanical storage when integrated with marine renewables.

            Offshore installation not only accounts for 40% of turbine cost, it supports an entire industry that becomes redundant once self-contained, stable floaters are adopted. Easy to understand why established industries hate disruptive technology, and the costly 80 metre long turbine blade has seen it’s heyday (offshore). Sorry, but that would be transformational progress. (why am I apologising?)

          • Mike Barnard

            More bizarro world stuff. I’ve been posting on CleanTechnica for eight weeks, not a year.

            Water pump? Digging a deeper hole.

            Once again, storage is necessary in small amounts when there are very large penetrations of renewables. GE’s Brilliant turbine has a good niche with very small amounts of local storage for a group of turbines to smooth grid feeding: intelligent, data-driven and real. Since Dave refuses to read references left earlier and respond to them, I’ll post this again. In reality, storage is only a small part of the energy smoothing and backup equation, and it’s needed in small amounts at a grid level, not a device level.

            Regarding offshore VAWTs, actually I have written about them and Dave just doesn’t realize it. Unsurprisingly, the overview was dismal. One of the two prototypes to make it into the water sank.

            Basically, Dave is a techno-enthusiast who has a magic bullet for non-existent problems. The cognitive dissonance is all his.

          • Dave2020

            On BusinessGreen – last year.

            “Digging a deeper hole.” If you say so, it must be true.

            I read the referenced material and the counter-arguments are contained above, but these points don’t support your views, so you think I didn’t read what you’ve written.

            How do past failures have any bearing on the discussion, other than to note that people learn from their, and other’s mistakes. This is a good thing, but one first has to be able to recognise one’s mistakes.

            The problems certainly exist, but I don’t have a magic bullet. Whichever development options are chosen, it’s a long hard slog. Foresight, and forward planning are always helpful.

          • Mike Barnard

            So, likely under a different moniker a year ago you disagreed with something I said and I’m supposed to remember this and you? Get a sense of reality, Dave. You are a pseudonym on the internet right now. Apparently I loom large in your world. As far as I’m concerned, you have popped up on CleanTechnica arguing about irrelevancies for the first time in my recollection. If we ever interacted before, I don’t remember, and there’s no reason I should.

            Pro tip: If you want people to remember you, use your real name and own your identity. Oh, and author some stuff. Comments on the ‘net are rarely memorably by author.

            You make no counter-arguments. Sorry, but inside your head a different conversation is happening. Then you write down some statements based on an argument you are having with an internal fiction. A conversation requires a coherent set of responses on both sides. You started with non-sequitors and continue with them. You aren’t having a coherent conversation, you are having at best an occasionally externalized internal monologue.

            Pro tip: stay within the confines of the conversation and be clear when you are introducing new topics.

            The failures of offshore VAWTs are current, not historical. They haven’t been proven to work any better offshore than on, it’s a side bet at best and the current research efforts are dead in the water. Recognizing mistakes would include recognizing that VAWTs are pretty much a dead tech. Recognizing mistakes would mean accepting that, but you are apparently incapable of understanding when statements you make about others are actually reflective of you.

            Pro tip: don’t make statements that are blatantly wrong about what someone says directly to the person who wrote them and referenced them. He’ll likely know you are wrong.

            You have this magic tech you allude to, and that apparently you’ve been throwing up at every chance for a while as CleanTechnica moderation is deeply tired of it. You reference tidal power, mixed with VAWTs, mixed with floating, mixed with water pumping, mixed with a fairy dust for all I know. If that doesn’t describe a magic bullet, it’s unclear what would.

            Pro tip: be honest and transparent about your intent and goals. If you have a tech, say, “I have this cool tech idea that I think is the best thing since slice bread.”

            Bluntly, the grid works on a series of components which together balance the overall grid. Generation of various types is a big set of components. Transmission across and within jurisdictions is another big set of components, apparently one you don’t like and refuse to accept when it crosses political boundaries. Distribution of electricity is another big set of components. Storage today and in the future is a minor set of grid components that will have advantages in terms of balancing the grid. It’s not nearly as important as tying grids together and sharing generating and demand loads according to every data-centric study I’ve seen. So far you haven’t said anything coherent on the subject. Optimizing components is a great thing. The best wind generation is the best wind generation. And the best transmission tech is the best transmission tech. Nothing makes VAWTs particularly worth bothering with outside of tiny niches.

            Pro tip: learn about the grid and the actual economics of it. At present you are arguing against economic reality, not with it, and not from an interesting and challenging perspective. I’ve been having discussions with European and North American energy-focussed economists who have nuanced and difficult arguments. You just don’t like connecting grids and putting components where they make sense.

          • Dave2020

            No, I didn’t expect you to remember, but it was under the same moniker. The Engineer comment threads have my name on them. No technology develops in an isolated bubble. It is all promoted or buggered up by political choices, received bias and vested interests. Dual purpose designs are more economical than building stuff to do only one job:-

            My proposals combine three jobs in one design and improve on each. We need renewables that work so much better the sceptics don’t have a single plausible (to them) alternative.

            “VAWTs are pretty much a dead tech.” Again, if you say so. The Technip engineers responsible for the ‘Hywind’ spar buoy think that the compromises and cost of floating a HAWT outweigh the compromises of using a VAWT, so they started the Vertiwind. Yes, it’s a struggle, and Statoil spent 12 years and £50m to develop one Hywind, but the US lost interest and Scotland’s not sure. Maybe it’s dead in the water, as a commercial design? We need something far better.

            You write of “magic tech . . mixed with a fairy dust” and you expect readers to take you seriously? I have described the designs above in terms any engineer would understand. The whole thing could be ‘reverse’ engineered with a little imagination. Naturally, the possible value of patents precludes putting too much detail in there. That problem frequently enters the discussions. I’ve referred you to some articles giving more details. Here’s another one:-

            The most recommends go to a guy who slates wind power. Too many policy-makers do the same. To win them over we the best we can devise. The best wind generation doesn’t impose over-capacity, it’s perfectly balanced in a system with a minimum total installed capacity. I think we’ve spent enough time on here, don’t you?

          • Mike Barnard

            “Dual purpose designs are more economical than building “stuff to do only one job”

            False. The example you provide is a custom niche, not a manufactured and scaled up grid solution. If dual purpose were always better, a lot more cars would also double as boats. As a useful rule of thumb, combining functions typically sub-optimizes both of the functions. This can be an effective overall solution — smartphones are a prime example –, but it doesn’t apply to singular devices for utility scale generation.

            “My proposals combine three jobs in one design and improve on each.”

            Extremely unlikely, closing in on impossible.

            Wind resources and tidal resources rarely overlap in the same location with the same quality. By definition then, one or the other will be sub-optimally sited. Second, tidal resources are frequently strongest at the narrowest points of larger bodies of water, which are incidentally favoured for bridges as well, hence the attempted implementation basically under the Golden Gate bridge. This further reduces places where a tidal + wind combination might be useful.

            Many tidal solutions are completely submerged with nothing even particularly close to the surface of the water. As such, they do not provide barriers to other uses or obstacles. Requiring that they have a large scale turbine on top of them would once again minimize potential siting for tidal.

            Storage has a completely different scale factor. Pumped hydro requires significant reservoirs. Battery storage requires a warehouse of batteries, typically with climate control. Pumped air storage requires underground caverns. Attempting to add significant storage to a singular device is a guaranteed way to minimize potential storage to the point where it isn’t of any particular value.

            GE has this figured out. They have a storage component that works with several of their wind turbines to smooth power to the grid, maximizing profits. But they don’t put the storage device in the turbine. It’s a component.

            Similarly, UGE and other major suppliers of home systems have separate inverter components because it’s the most economical and sensible way to provide storage with generation. This has remained true at every scale, regardless of the pipe dreams of backyard tinkerers.

            “The Technip engineers responsible for the ‘Hywind’ spar buoy”

            The Hywind / Vertiwind team hasn’t managed to float a prototype and their only claimed win was a new website design in their last annual update. There is nothing close to a realistic product there. That some engineers think that they might get somewhere is relatively immaterial. One of my acquaintances thinks Makani is the coolest thing ever, knows it will likely never generate any useful electricity but wants to work on it anyway because it’s so cool. Enthusiastic geeks don’t mean that what they are enthusiastic about is viable in any way. Referenced here as I’ve already assessed it of course:

            As for magic tech and fairy dust, you have made some arm waving statements with provably false starting assumptions, claim to be withholding material because of concerns that someone might steal it — who would bother given the above? — and have provided zero details of any relevance. If you actually tried to build your tech, you would rapidly run into the massive compromises it entails. Because you haven’t built it, you still believe it’s magic. Your sprinkling of irrelevant articles like Ms. Emshey’s is the fairy dust. Distributed small scale wind energy isn’t particularly relevant or worthwhile because slow, low-to-the-ground, turbulent wind resources are crap not because the technology to capture them is bad. Putting up a big wind turbine at the edge of town, not a bunch of little ones on the houses is the sensible approach because physics.

            As for minimum installed capacity, gas generators are often at 10% capacity factors because they provide peak power. Fukushima dropped its entire fleet of nuclear reactors which provided 30% of demand and didn’t have a blackout, mostly because they spooled up excess generation capacity that they already had (and partly due to efficiency measures). Every developed country has hot standby capacity of one sort or another to deal with the loss of its major generating assets due to technical or transmission failures. Building overcapacity is required and done where it makes sense to build them.

            You seem to be back on this silly obsession with the UK not building more wind generation capacity onshore because you are against wind generation onshore, not because of grid realities or economics, as far as I can tell. If you actually understood grid reality and economics of energy generation, or for that matter engineering, you wouldn’t be obsessing about a three-in-one floating VAWT with tidal generation and storage.

          • Dave2020

            In a future grid reality, gas peaking plant is displaced by storage. I thought that was obvious. Why would we still have fossil fuels and a ‘capacity market’? It’s uneconomic and open to gaming. We need to get rid of it.

            There are none so blind as those who refuse to see.

            “it doesn’t apply to singular devices for utility scale generation.” If you say so, it must be true. But actually, you fail to understand that BGES is NOT a singular device – that’s the whole point. Each unit is but a part of the total storage capacity, shared by multiple sources.

            “Extremely unlikely, closing in on impossible.” Not if you open your mind it isn’t.

            “There is nothing close to a realistic product there.” Ah, a point of unanimity. Yes, I couldn’t agree more. The Vertiwind is a weak design, but not because it uses an inefficient VAWT. It’s because the vessel it floats on is a totally unproductive substructure. It should double as a storage vessel and be stabilised by a four-float WEC. This makes it self-contained and towable, as a finished unit, thus lowering O&M and installation costs considerably. (Hence no call for jack-up barges.)

            But Mike hasn’t got any understanding of the benefits of before-generator energy storage, so this simple engineering solution must be impossible. He also chooses to overlook the cost of the direct drive technology developed for next-generation HAWTs, never mind the fact that the generator is replaced by a variable-displacement water pump.

            This pump is all that’s required to maintain optimal rpm of the turbine, from very low wind to running during gales and also as a brake to stop it. This is low-cost, low-maintenance and very durable engineering, ideal for the marine environment.

            The frequent high seas and wind around the Atlantic Array, plus the difficult sea bed, were factors given by RWE for its cancellation. Do you think that’s a sub optimal site for a combined wind/wave floater? I very much doubt it and I’m certain there are many more like it, the Argyll Array to name but one. The new designs would be a fairly benign presence and create less disturbance during installation. Maybe the basking sharks won’t notice.

            RWE said it would focus on “other less technically challenging offshore projects”. “As the offshore wind industry develops over the next decade and on the back of more viable technologies being demonstrated, expected innovation and cost reduction may in the future open up opportunities in the more challenging areas, such as in the Bristol Channel,”

            We have the innovation. Let’s get on with it. You insist I must do the R&D. You’re joking, right? You reckon I’m a millionaire entrepreneurial genius? Sorry to disappoint you. Why do you think I need to try to inspire ANYONE who can be bothered to listen? Read again:- Even the professor feels that the (innovation) situation is hopeless.

            There is such a huge surplus of energy out there to harvest, “optimal” is next to irrelevant. A HAWT has to feather its blades when the wind speed rises, so that potential energy just flies by. Ignoring the wave energy is dumb. You’re putting in expensive infrastructure to transmit power to the grid, so harvest every available source. It’s less variable and cheaper that way.

            The Swansea Bay Lagoon is a short distance away and could easily have an umbilical link to a new design of Array. Constructing a solid breakwater makes no sense, when you could use hollow caissons instead and store loads of energy.

            There are none more damaging to progress than those who are too stubborn to change their minds.

          • Mike Barnard

            And down the rabbit hole Dave goes.

            Build it. Test it. Get someone else to test it to actually prove something.

            In the meantime, you are just a time waster on the internet who is trying to delay or defer actually viable wind generation from being built.

            Your opposition to actually working wind generation is part of the problem, not part of the solution.

          • Dave2020

            To return to the headline topic – what made VAWTs so great in the 1890s? Why are they “also-rans” in 2014? It’s nothing more than a journalistic trick to bolster Barnard’s obsession, which permeates all his writings. They have a niche role, yes. It just so happens that that niche role is a teeny weeny bit bigger than Mike wants it to be. His hubris can’t cope with that, so he has to undermine vital work on innovative energy storage. Your erroneous analysis is a barrier to human progress Mike.

            Then you try to obscure your multiple mistakes (on engineering, economics, innovation strategy, grid operations) by portraying me as the fantasist. Investing massively in renewables, without a commensurate level of BGES is really, really dumb. Get real for heavens sake. The fossil fuel fat cats will be delighted to see the introduction of energy storage delayed (by you) for several decades. That strengthens their business case and political influence, in advocating fracking, UCG, and drill baby drill.


            My £50k seed investment would never build a (minimum) £50m pot to cover the Rdd&d of storage-integrated marine renewables. That’s the reality. I have to be realistic and pragmatic.

            The whole project could have been launched five years ago, when I put my proposals to the National Grid ‘operating2020′ consultation, but these parasites demand an annual profit of one or two billion, and strict limits on R&D spend. (£13m in one year = 0.01% of turnover) Don’t tell me to spend my pittance of savings for my old age, on R&D – tell them not to be so effing greedy.

          • Peter Gray

            Thanks for trying, Dave, but no amount of quantity overcomes a shortage of quality, and I don’t see much of substance that supports your arguments (such as I understand them). I didn’t pore over every one of your linked articles, but the second-to-last is a fairly well known account of the utilities’ transition due to disruptive technology, with no clear connection to your tide/VAWT notion, and the last one seems to be far afield; something to just toss in randomly.

            At that point I don’t have enough time or interest to explore and refute your whole catalog – with that sample you discredited yourself.

            You still haven’t replied to Mike’s or Bob’s or my versions of requests that you do the real work of building a proposal and model, with clear problem and solution statements. I haven’t seen any explanation for why you’re ignoring that step.

            I’ve seen the same kind of thing far too many times, starting with the perennial inventors of perpetual motion machines, and continuing to all varieties of conspiracy theory devotees (that’s kind of why I mentioned the anti-vaccine, anti-GMO, climate denialists, and their ilk). When their ideas are not accepted by the genuine experts in the relevant field, it’s always because of rigidity, ideological blindness, current thinking excluding new thinking…

            It’s a big world out there, with lots of creative people in it. If you have a good idea, it’s your job to demonstrate how it solves a real problem. Then you’re likely to find investors who can help make it real. After all, plenty of investment $Ms go into really stupid ideas, like mining the asteroids for platinum.

            If you don’t do that, but continue tossing out grab bags of unrelated links and rhetoric, you’ll likely find a lot less patience than you’ve seen here, by people you’ve been so quick to denigrate.

          • Mike Barnard

            Dave’s opening comment included:
            – “cognitive dissonance”
            – “hubris”
            – “fails the logic test even on the simple issue of bird strike”
            – “exclude disruptive innovation as Mike does, for no good reason”
            – “does us all a gross disservice”

            Then in his last statement after he spilled many off-topic and irrelevant comments and words he says:
            “Cognitive dissonance is a very uncomfortable feeling, so they [Mike and Bob] slip into personal abuse instead of debating the issues in a calm and rational manner.”

            To be clear, he’s shown that he is against onshore wind turbines in the UK, obsessed about some gadget which he feels is ‘the answer’ despite no technical papers or proofs-of-concept, and ignores actual grid studies and empirical evidence which shows that storage is only of future and relatively minor importance in renewables deployment. And he’s made all of those statements in the comments thread of an article about vertical axis wind turbines being an inferior technology which should stop getting press, so he’s just off topic generally.

            Dave starts with a-factual abuse, then complains about receiving factual corrections. Dave is the one with the closed mind who doesn’t understand what disruptive innovation means — I recommend Christiansen and Raynor’s excellent The Innovator’s Dilemma for his edification — and is abusive. Dave is the problematic element in this discussion, but doesn’t understand that either.

  • Mike Barnard

    Note: somewhere along the way, the two graphics of turbulence from HAWTs and VAWTs were reversed on the page left for right. Please read it as such.

    • Peter Gray

      I figured that out, but thanks for catching and noting it.

  • JamesWimberley

    Mike Barnard is the (necessary) house sceptic here. I’d be interested in his take on other technologies with promise but not yet there commercially, and maybe never: concentrating solar power, wave, biofuels, and (my favourite) EGS geothermal. I take it that wet geothermal, thermal solar with storage, tidal, and biomass are mature commercial or near-commercial technologies, with the usual cost issues but not really subjects of hype.

    For connoisseurs of perpetual motion machines, try Blacklight Power (; Hydrino transitions! It’s all based on nonstandard (i.e. wrong) quantum mechanics, so the scam is not disprovable by you and me.

    • Mike Barnard

      Well, I’ve said a couple of things about oceanic power systems on Quora. Suffice to say that there just aren’t a lot of production units of any type anywhere as they tend to be removed as nonviable after a year or two. This is true for both wave and tidal, so I’d disagree about the hype on tidal.

      Biofuels work in Brazil where sugar cane is very high in sugars so ethanol output is high, they grow enormous amounts of it and the government is happy to mandate that all vehicles be dual fuel. Elsewhere, not so much. It’s quite arguable that corn-based ethanol in the US is an unmitigated waste of money.

      I’m a big fan of geothermal, but I happen to know enough about plate tectonics and geology to know that large concentrations of it are not available widely and other areas have much higher costs. Useful where it’s relatively cheap and easy. Elsewhere, not so much. On the other hand, small scale heating and cooling assistance is interesting and easy to implement for low rises. Scaling gets expensive rapidly.

      EGS geothermal in specific I hadn’t looked at, but a quick glance tells me that it will likely have the same challenge that tracking does, which is rapid well drop off of potential after the first year. This is viable for extraction of shale gas but redrilling or relocating an electricity generating unit annually doesn’t seem that viable to me. Perhaps there’s an answer for that, but I haven’t dug into it enough to figure it out, and likely won’t. I’m a bit of a wind energy obsessive, in the event you hadn’t noticed. 😉

      Haven’t dug into concentrating solar power particularly or thermal storage with solar, so I don’t have an opinion.

      In general, I’m in favour of large scale and rapid deployment of working technology over R&D in areas which haven’t proven viable after decades. Lomborg and others keep pushing the R&D over deployment argument and it’s seductive. The troll needs to be dragged out into the sunlight so that the thickly caked, cheap makeup can be seen for what it is, and the warts and cracked skin under the fishnets show up clearly.

      Global warming needs working solutions, not future hopes.

      • A Real Libertarian

        AFAIK biofuels are worth investing in for airplanes, but otherwise?

        Not worth it.

        • Bob_Wallace

          Oceanic shipping. Remote construction. Some agriculture. Legacy ICEVs.

          • A Real Libertarian

            Those too.

  • Shiggity

    I think after all the ‘good’ places are taken for wind with the giant horizontal turbines, we’ll start seeing VAWT’s more. VAWT’s don’t scale quite as well yet.

    There is a bank near where I live that has these.

    • Bob_Wallace

      If by scale you mean size, the US installed over 200 very large egg-beaters back in the early days. They were all taken down after a while.
      China started a large-sized VAWT program a few years back and, so far, nothing has come from it.

      Every few months someone announces a new, wonderful VAWT but generally never produce any performance data. Then they fade away.

      If someone produced a VAWT that performed better than a HAWT then you know wind farms would be using them. Performance wins.

    • Omega Centauri

      If the goal is to make a fashion statement rather than to generate practical power, the VAWT makes sense. I think your bank put a a sculpture, that it can claims makes them green.

    • sault

      If all the “good” places for wind power generation are taken by HAWTs, we’ll probably already be generating more energy than we need with just these turbines:

      While transmission of this energy to load centers will be an issue, that is a lot easier problem to fix than trying to shoehorn VAWTs into the energy mix instead.

      • Bob_Wallace

        Heck, let’s use an even prettier picture. One that includes our most excellent offshore wind resources.

        Do remember, roughly 80% of the people in the US live within 60 miles of a coast. And that number probably doesn’t include those living close to the Great Windy Lakes.

  • D Wright

    Once in a while two-blade HAWTs are mentioned and even built. Apparently those are not as efficient as three blades or they would be developed too.
    What about a double-sided two blade turbine? The downwind blades could be larger so the nacelle would always face into the wind. The rotors would be set apart (front to back) for the optimum energy production and minimum turbulence.
    Wouldn’t this theoretically almost double the capacity on one foundation?

    • Bob_Wallace

      What I seem to remember about two-bladed HAWTs is that they ‘ran rougher’ because there’s some change in wind pressure right in front of the tower. That caused uneven loading. With three blades the mass is spread so that there’s less tower effect loading.

      Downwind blade suffer even more from the tower effect. They have to run through an area of disturbed wind on each rotation as them pass behind the tower.

      • Peter Gray

        I think the other, maybe bigger problem is that when the blades are vertical, the upper one is more heavily loaded, putting stress on the rotor shaft and a lot of torque around the tower axis.

      • Hans

        Another argument against two blade turbines is that they are less pleasant to look at. Viewed from the side it seems like the blades appear if they are vertically aligned and dissapear when they are horizontally aligned.

    • Mike Barnard

      Three things.

      1. Downwind turbines have sound emission problems as blade pass through the wind shadow creates stall conditions, just as a tiny subset of wind turbines in some areas see stall conditions above the wind shear line creating thumping sounds. This was discovered in testing in 1987 and the few wind turbines that were built based on that premise have all be decommissioned. Of course, the paper outlining the testing is cited very regularly these days by antis as ‘proof’ that governments know wind turbines are killers because idiocy. The electricity generation characteristics were likely worse as well due to reduced efficiency and higher maintenance due to the vibrations, outweighing the trivial electricity required to rotate a nacelle into the wind.

      2. A guy named Doug Selsam designed, built and still tries to sell a multi-rotor on a shaft turbine, with the shaft facing into the wind. Paul Gipe tried to test it in California at his test facility but it was extraordinarily finicky, requiring so much maintenance and tuning that it was non-viable. Selsam still makes grandiose claims for it, but there are zero in production today.

      3. Facing into the wind is easy in good wind resource areas. The wind have strong seasonal prevailing directions, are laminar and non-turbulent. It just doesn’t take much electricity to rotate the nacelle to point in the right direction, and brakes mean that it takes no electricity to keep it there.

    • Peter Gray

      As noted in the performance graph, the theoretical maximum power from any turbine is the Betz Limit of 59.3%, and that’s with an infinite number of zero-drag, infinitely narrow blades. Of course that’s a structural impossibility. There’s little to be gained, and a lot to lose, from using coaxial rotors. As you can see from the graph, the best 2-blade performance is already close to 80% of the theoretical max, so there’s not much left for the second rotor to harvest, aside from the problems of turbulence and a long, heavy shaft.

      Ignoring structural issues, more blades gives more performance, but with diminishing returns. Going from 1 blade to 2 can increase efficiency by ~6%, from 2 to 3 can yield 3%, and so on. But the cost and weight of the blades goes up steeply.
      I haven’t found any theoretical justification for 3 blades being ideal, so I’d interpret that as the best known compromise between all the cost and performance factors. Perhaps if someone comes up with an extremely strong and very cheap material, we’ll see turbines with 4 or 5 blades. But it would have to be a huge gain in material properties per $ to make it worth going after 1-2% higher efficiency.

      • Bob_Wallace

        Here’s an interesting piece from Paul on one-blade HAWTs.

        And it looks like Aerodyn Engineering is building a 8 MW two-blade downwind turbine.

        • Peter Gray

          I don’t have data to prove it, but one blade would seem to create horrendous mechanical problems. What’s the point, other than to save a fairly small amount on materials?
          Maybe 2 blades downwind would have some simplicity advantages, and no worries about noise off-shore. I wonder why nobody seems to have considered mounting a self-aligning fairing on the tower? That could greatly reduce turbulence and wasted energy.

  • Michael Berndtson

    Nicely done. Explained very well.

    Speaking of vertical axis wind turbines. The shopping “mall” near my house installed ten vertical axis turbines after a major face lift. Ignoring the efficiency issues and all – the problem is not putting anything into operations and maintenance. So they sit idle frequently or have been taking down.

    The shopping mall is owned by a weird dude. Here’s one of the infamous art sculptures:

    And the vertical axis wind turbines that rarely spin:

    The car-kabob or skewer was featured in the movie Wayne’s World and has been preserved and put in storage. So it’s available if anyone’s interested. This sculpture and others were an expression of man’s reliance on the automobile and our wasteful culture. There was a sculpture of a big hunk of trash. Actually, the mall owner wanted to simply tease the good folks of Berwyn back in the day.

  • Omega Centauri

    It think its just that VAWTs look really really cool. And they are non-intuitive with exotic names, so you just feel that there must be sure genius behind them. Sort of a designer (artist) version.

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