Invest carefully; wind energy ‘innovations’ are rarely kosher

Last update: August 14, 2014

Wind energy is a big business world-wide, with billions of dollars flowing around at various levels. And as in any large and growing market, a wide variety of people are attracted to it.  Most are solid, competent professionals. Some are superstars.  A slightly larger percentage than in other fields are engaged in part because it’s the right thing to do, not just something they can do well and make money.

Along with all of the professional people, there is a physically/economically optimal design that the vast majority of wind generators have converged to: the three-bladed, horizontal-axis wind turbine. This is the most efficient design due to pure physics: the blades are always flying in clean air, at the optimal angle to the wind, at the height of strong wind and have the added component of aerodynamic lift as another vector of force.

There are about 240,000 of them worldwide in sizes ranging from a few kilowatt capacity to 7 megawatt capacity both onshore and offshore, in rural and urban areas. Four out of five of the top selling small wind turbines are horizontal axis two- and three-blade wind turbines (only one 2-blade one, but it’s a reasonable choice at this scale.) They are generating all but a tiny fraction of a percentage of the electricity harvested from the wind in the world. They are undergoing constant incremental improvements in design including:

  1. Low-wind vs high-wind models
  2. Variable pitch blades
  3. Gearless vs geared nacelles
  4. Slight variants of blade design for aerodynamic efficiency
  5. Leading edge coatings
  6. Tower design
  7. Base design – rock-anchor vs concrete-base vs tethered floating vs. bottom-mounted offshore

As examples of the types of innovations that are constantly underway, yet aren’t particularly sexy, here are three recent stories. In the first, a duo at an aeronautical university realized that they had a design for a gearbox that would last longer than current gearboxes and are looking to put it into wind turbines. In the second, software-based predictive maintenance that has been used for years in other industries is being applied to wind farms to optimize maintenance schedules, purchases and hence costs. Both of these make gadget geeks and a lot of enthusiasts yawn, but there is enormous money in shaving a percent here or a percent there off of costs when the costs are in the billions. The third is more exciting to your average tech-head, but it’s still incremental supply chain innovation: a giant, specialized ship for installing offshore wind turbines that can transport and install eight to ten, 6 MW wind turbines in a single trip.

Sandia Labs, the pre-eminent wind generation test facility in the world, got out of the business of testing and developing vertical axis wind turbines (VAWTs) in the 1990’s due to their proven ineffectiveness compared to horizontal axis wind turbines.  They are re-opening their historical research to see if some of the design characteristics of VAWTs might make them more suitable for offshore wind generation, where the different compromises might be economic, but it’s unlikely that VAWTs will capture more than a tiny fraction of the market compared to HAWTs even if they prove to be equivalent for offshore wind. Kickstarting a new technology and new supply chain for one niche when that niche is well served by existing technologies that also work on land is likely not optimal. This is a counter-example to the rest of the examples below; it’s thoughtful, it’s being done with full knowledge of prior art, it’s being done by a top notch organization with a long history in wind energy and it’s being done because they think that the compromises might favour VAWTs for a specific niche. It’s a stretch, but no one is spending big bucks on this yet, just enough money to dust off the research and think through applicability to the niche.

There are, of course, people who don’t fit into the wind industry categories in one way or another. Perhaps they aren’t particularly intelligent or competent. Perhaps they aren’t professional enough to carefully assess prior art to see if their great idea has actually been fully assessed and declared unworkable 15 times before. Or perhaps they just see the opportunity to make a fast buck off of people who think that a disruptive new wind generation technology will be worth a lot of money. A subset of these people come forward with ‘innovative’ and ‘new’ wind energy technologies which they claim solve the mostly non-existent problems associated with the current leading technology.There are a few dozen designs in play at any given time, which have perhaps tens of thousands of instances with very small generating capacities world wide. These include variations of savonius windmills, darrieus wind turbines and a variety of flying or compressing designs. Almost none of them are producing electricity right now anywhere in the world at anywhere near utility scale; most of the ones that are producing any electricity are for off-grid applications such as sailboats or local-residence supplemental electricity (both of which are very well served by small scale horizontal axis wind turbines or HAWTs).

As a thought exercise, look at the picture of a simple savonius windmill below and guess reasons why it’s never going to be as efficient as a horizontal axis wind turbine.

The challenges include the drag of the concave surface rounding into the wind, the lack of an aerodynamic component to the force, the limitation of speed of rotation to maximum of the speed of the wind, cyclical change in load on the bearings as the unit rotates, the lack of optimal angle of attack for their scoops the majority of the time and the sheer volume of material needed to harvest energy from a volume of wind. At that, however, it’s a very cheap, high-torque unit that a farmer can make and maintain themselves out of materials at hand to pump water. That’s about all the savonius wind turbine is really good for; that’s its niche. It’s moderately foolish to try to make it more than it is.

Yet one ‘inventor’ created a version of this that used injection molded fiberglass with dimples for aerodynamics on the leading concave edge, magnetic levitation and a handful of other ‘improvements’ that merely resulted in it being a very expensive ineffective generator of electricity. He even claimed that wind would somehow fill the inside of the hollow structure generating additional force. And he was actively peddling this intellectual capital for sale. The only good thing about this situation was the business niche that was being targeted: charging backup batteries for remote communication towers using low-maintenance renewables instead of diesel generators. This is a design point and market that could be worked toward using existing solar and wind generators, and there might be a nice small business in there.


A higher profile ‘innovation’ is Saphon, which actually got a TED spot for something that is so obviously deficient that any one remotely related to the wind industry would have laughed it off the stage. Professionals’ comments regarding it are invariably brutal.

Its failures include inability to scale due to mass of the conical device they use, no ability to feather the cone so it will likely fall over in high winds and a mechanical piston actuator that also won’t scale and introduces massive inefficiencies. The patent it claims represents its breakthrough is actually for a different device than the one they are promoting. They explicitly call out many of the myths denigrating wind generation as real in their promotional video and then claim their design solves these almost non-existent problems. The two principals have no background in wind energy, but one is a former investment banker who specialized in getting people to invest money in companies. Is there a niche where their product is better than a tri-blade HAWT? It’s extremely unlikely in our physical universe, yet this doesn’t stop them from seeking new investors, creating prototypes and getting a remarkable amount of fawning press including being shortlisted for an African innovation award recently. The principals are much better at PR than engineering.

An idea what won’t stay buried is shrouded or cowled wind turbines, where a bulky external shroud concentrates air flow on a smaller wind turbine. This idea is challenged in ways similar to the Saphon, in that scaling up typically produces a massively heavy and shear susceptible bulk on top of a tall, relatively slender pole. Effective harvesting of wind requires getting the generator up into the air where the wind is stronger and having a broader surface area to harvest from. All the shrouding does is reduce efficiency of a three-blade HAWT with the same diameter and much less material than the shroud. Yet this is re-invented with prototypes being funded regularly, as if no one in the history of wind energy has ever in the past thought to apply the Venturi effect to wind generation.

High-altitude wind is another area with a lot of funding spent on research and development and no production generation of electricity.  Some products such as Makani put solid and relatively heavy wings with blades and generators at the end of long tethers / transmission cords (for my full assessment of Makani, please see this: Google’s Makani airborne wind generator flies a bit lower when you look at it closely). Other such as Kite Gen Research put all of the hardware on the ground and use a relatively simple and much safer parafoil kite to haul line out in the power zone, and reel it back in out of the power zone.  Others use blimps with either blimp-shrouded turbines or variants of airborne savonious turbines. They all promise to tap into the greater potential energy of wind at higher altitudes. There are any reasons why these technologies haven’t taken flight in the market. The complexity of launching, controlling and retrieving a flying object autonomously is enormously more difficult and has a much higher likelihood of failure than just building a taller, stronger mast that doesn’t move. Modern, utility-scale wind turbines are already in higher and steadier wind altitudes, so differential gains aren’t as great. These designs require unobstructed downwind ranges that are quite long. They fly higher and have longer tethers, effectively creating a much larger and potentially varying no fly zone than fixed position, tower-mounted wind turbines. Especially for the solid flying wings, the potential liability in case of failure is much harder to certify and insure, greatly increasing the cost of business. Once again, there’s a small niche for some of these in very remote sites with temporary facilities where the downsides don’t matter and the ability to pack them into small spaces has strong advantages. There is a business model, but it’s not a mass market one.

Many of these innovations claim to have found a way to exceed Betz’ Limit of 59.3% of potential energy harvested from a volume of wind.  None have stood the test of third-party, independent testing. Some claim that Betz’ Limit doesn’t apply to VAWT technology and then point to Sandia Labs documentation which clearly says that it does. Virtually none have performed ISO standard full lifecycle cost assessments, published them and had them audited by independent third parties.

Most claim to be quieter, although virtually none publish side-by-side noise evaluation tests with similarly scaled HAWTs to prove it.  Many claim to kill no birds, although there is no proof of that claim either (and of course utility scale wind generation is the best form of generation for birds from a species perspective.) Some anti-wind lobbyists have internalized these claims without understanding them and actively promote the idea that there is a better alternative for their pet concerns.

Then there are the situations where there doesn’t even appear to be a physical product of any sort. A firm in the western US received $4 million up front a handful of years ago from the municipality to build a factory for savonius-style wind turbines. It has delayed breaking ground on its factory for four years, doesn’t have a working website and is saying delays are due to bird tests (not true according to the agency that was performing them), a completely unrelated scandal many states away and the need for more money in the bank. It appears to be nothing more than a large scale scam that has already netted them around $4 million and they are hoping to get $10-11 million more. All for a conceptual variant on that barrel split in two above.

There are minor niches where alternatives to tri-blade horizontal axis wind turbines are effective.  There is a vertical axis design, for example, that self-stalls in high-winds, making it effective for remote locations with regular very high winds, e.g. Antarctica.  There are a few darrieus variants that are remarkably attractive kinetic sculptures that happen to generate electricity as well, where the aesthetic value makes the high cost per KWh palatable. Some of the blimp-based design are good for remote locations.

Image courtesy of

So, how can you inoculate yourself against putting money into a bad wind energy product?  Ask these simple questions and if any of the answers are Yes, be suspicious:

Technology Red Flags

  1. Do they claim to exceed Betz’ Limit?
  2. Is it an old technology claiming to be a new technology?
  3. Is their product just a design concept as opposed to at least a working and tested prototype?
  4. Are the only test results from tests that they have performed as opposed to independent, third-party labs, and do they expose the numbers?
  5. Are claimed patents for devices other than the one they are demonstrating?
  6. Are they claiming greater efficiency than existing generation technologies based on anything other than an ISO standard full lifecycle accounting that has been independently assessed?
  7. Are they claiming to integrate storage into their wind generation device without a market niche need?
  8. Do they respond to documented criticism of their technology with factual rebuttals, or do they attempt to discredit the authors of the criticism?

Business Model Red Flags

  1. Do the principals have backgrounds entirely in fields unrelated to wind energy?
  2. Are they starting from a product as opposed to a specific and tightly targeted market niche?
  3. Are they claiming that their product will replace utility-scale three-blade wind turbines?
  4. Does the product introduce major new liabilities e.g. downwind throw of solid flying wind turbines and cable, or varying flight obstructions?


  1. Do they disparage other wind generation technologies to establish their technology’s superiority?
  2. Do they have an online presence that is merely a static web-site or missing entirely, without normal means to contact them such as email or Facebook?

For a rating of currently active wind technologies, have a look at the companion post to this one, Good and bad bets: new wind technologies rated.

The wind industry is disruptive because it is supplanting fossil fuel generation at a reasonable cost. That reasonable cost is due to decades of incremental innovation and major supply chain and business innovations, not radical technical innovations. The most effective technology was chosen a few decades ago, and it’s been getting steadily better ever since.

The wind industry isn’t going to be disrupted by someone with an idea and a Powerpoint pitch. If someone is approaching you with a great investment opportunity based on a ‘new’ wind generation technology, be aware.

A short version of this post has been published on at The fee for the published piece was donated to, which is devoted to building a strong global climate movement.


  1. Lyn Harrison, InsightWind · · Reply

    Well done Mike. This has needed saying for a long time.

    1. Thank you, Lyn. Saphon being short-listed for an African innovation award tipped me over the edge in terms of moving material from Quora to here and sharpening my points.

  2. aerofox · · Reply

    11.Are they claiming to integrate storage into their wind generation device? (Special case: GE is allowed to do this because it has proven it knows what it is doing and the market.)

    I don’t understand this claim in your top 11 caveat emptors. Are you designating this 1 company as the “be all know all” that can inter- tie in energy storage to its renewable product line. There are several other companies besides this one that can integrate storage (net metering grid-or battery backup) with their renewable energy technologies Big Wind or small wind, although the scale of storage may vary. Pls. explain if something else was meant by claim 11.

    1.Do they claim to exceed Betz’ Limit?

    This is also possible and has been done in turbo-machinery (real performance in some ideal case environments), or in an inviscid or theoretical environment (wind-tunnel) because of flow perturbation. A common, but true claims of ducted machines is the ability (at least on paper) to exceed the Betz limit in the wind space, more particularly in the water space where volume is finite as opposed to infinite (air). . There is no shortage of science on that, whether reference area is the exit diameter or the “frontal area” (turbine disc). No ducted machine (air), non-turbo has shown in practice however to exceed Cp~.593, after viscous effects (friction, shear, turbulence, mechanical losses from load applied, heat and wiring losses), but then again, neither has any HAWT (un-ducted) either. I would also argue that is very possible for an unducted HAWT to exceed the Betz limit as well depending on terrain siting, ground effect, and in the water space (tidal basin depth)-it goes back to flow perturbation, which is a premise of the Betz theorem-unperturbed flow upstream and downstream of the actuator disc (Froude), uniform pressure distrbution on a frictionless actuator disc (of infinitely thin blades).
    The reason why turbines (non Brayton cycle) rarely if ever meet the limit is due to the impossibility of a friction-less prop, but flow can always be altered and controlled.

    I would suggest you read up on the specifics of the Betz limit , and its basis as a guideline and to what machines it applies to. Fluid Dynamics 101. And no, Kutta-Joukowsky condition is not techno babble.

    1. Thanks for your comments, aerofox.

      Regarding storage, I’m using GE merely as an example of an existing company with proven insights into the market and knowledge of where integrated storage of limited capacity has a market niche. In my experience, wind innovations by new companies claiming integrated storage for utility-scale generation are a red flag; the principals have internalized the myth that wind farms need storage and are claiming to have solved the problem. In reality, there is very little storage on the utility grid today with over 200,000 wind turbines generating electricity. It just isn’t necessary until very high levels of penetration. It’s an indication that you should assess the claims more carefully, not a statement that the company’s solution is necessarily wrong.

      Regarding Betz’ Limit, thanks for the details, but my point stands. No one who is grounded solidly in the real world would claim that their device exceeds Betz’ Limit in real world testing regularly, or that they are 2-3 times more efficient than utility-scale HAWTs. Both of these claims have been made by the Saphon principals in the past year, as well as by a VAWT peddler recently to me. While it is theoretically possible, under improbable ideal conditions to exceed Betz’ Limit for a very short period of time, in reality the claim is another red flag which should cause people to view the product and company very skeptically.

      1. aerofox · ·

        well, thanks for clearing that up. and I would agree that after “viscous” effects or real world operations as you describe it, very few non-turbo machinery (i.e. no Brayton cycle) if any, wind turbines (new or old design) under ideal conditions, can “routinely exceed the Betz limit” .

        the allure of the ducted wind turbine has been the rosy lab results and paper results that show mathematically it is possible to exceed the Betz limit with a ducted design , but in operations, unsteady aerodynamics take over and the friction loss (flow separation) from ducts are well known to negate the benefits of the ducted genre. only so much can be done with passive and active mechanical load controls on any type of wind machine. the thrust effect is often misinterpreted as beneficial, it may or may not be. All that matters is the rotor pressure drop and rpm improvement. That’s where all the work is done. Or just make the prop diameter bigger on an un-ducted machine. (van Bussel).

        I would disagree with you on the water space. however, constant flowing water (Hydropower) and marine hydro kinetics when in a finite space are capable of exceeding the Betz limit, but then the flow is nearly ideal in the hydro space. Finite volume and controlled flow changes the actuator disc theory-which really is a theorem for air (wind) in a dimensionless volume. water is 832x more dense than air, it sinks, and cavitates. there are several existing machines in the water environment that do exceed the Betz limit-because of flow perturbation, ergo Kaplan turbine and others, as an example – which is a reactive turbine (non-Brayton cycle). The machines geometry (non-symmetrical) plays a role as well, but not all non-symmetrical designs can exceed the limit. And that is not opinion, but science fact. feel free to look up water turbine efficiencies.

        As far as some of these “questionable designs” well it’s up to the yahoos and the yahoo’s investors to prove their claims in the real world. Especially the one DAWT about being 2-3X more efficiency (you know the one I’m talking about). It’s apparently bird safe too!, although no scientific studies have been done to prove that claim. None of their working prototypes have any public information posted / power curve. Again the proper reference area is the duct exit area, or the “inference area” or “area inscribed by the circle” I will take the “range where the deer and the buffalo roam”, a log cabin and my own small wind turbine design over that “Betz Beater” any day. Maybe you should call them to have them post their numbers. I tried and got zilch from them…other than ” it’s is not yet ready for market and still under development”

        No matter the claims of any new wind machine, however one may judge them to be outlandish, we need more RE equipment out there, whether VAWT, DAWT or conventional HAWT. It’s clear that Big Wind is scalable and diameters keep on increasing. But even at 200,000 globally installed, its not nearly enough. It is approx. 3% of installed capacity generation in US. (EIA). Lets not forget hydropower is the largest single renewable energy source in the US (5%), not wind, not solar and it’s cheaper than NatGas. Pls. factcheck my numbers. And if we list Big Wind and Big Solar by their net capacity factor or net installed capacity factor and generation, that number gets cut by more than 1/2. More reason for more equipment Big or Small. I apologize for the long post.

  3. zevkirsh · · Reply

    what about kite power generally? There have been numerous failures so far. Im of the opinion that kite systems are simply dealing with overwhelmingly powerful winds with no robust method of harnessing that energy.

    Fundamentally i dont think kite power is a scam but simply put….going above 200meters to capture high speed wind as an energy harvesting strategy is not ready for primtetime yet. Thoughts?

    1. I cover aspects of high altitude power in a related post which talks about the most efficient design for wind turbines. I’ve been considering extending this post with a paragraph on high altitude wind. For now, I think the important question to add to the existing eleven is that of degree of additional liability due to the generation device. For high altitude wind that includes both air traffic obstructions and downwind reach of debris in the event of failure.

    2. Kuba Ober · · Reply

      If it’s done by actual engineers who know their stuff, then yes, most certainly kite-style power is doable. Makani Power was recently acquired by Google. I’d have no problem hiring any of their people, they are top notch. They are not fooling around, they actually do hard core engineering across the whole project: controls, structure, aero, etc. Just last year they have demonstrated fully autonomous flights that include deployment, hover, power generation and retraction. Look mom, no hands.

  4. mphase · · Reply

    I want to start by saying that I agree with all of your main points about the alternative/innovative wind turbine designs that individuals are flogging. The one thing I would argue is your use of “physically optimal design” in the second paragraph. I would say that the typical horizontal three bladed design in an “economically optimal design.” You are getting your best bang for your buck but there are alternative designs that may be more efficient based on the physics (this is why the shrouded designs “won’t stay buried”) and the only thing keeping them from getting scaled up is the huge cost. But I’m really just arguing semantics since I agree with all your main points.

    1. That’s a fair statement. I’ll consider amending it.

  5. Pat Kelley · · Reply

    It’s good to see some technical observations that recognize how much “snake oil” is being peddled with respect to “innovative” wind turbines. One thing I would like to point out is that no one seems to be taking a systems engineering approach to evaluating these wind power technologies. By that I mean there is an obsessive focus on unit turbine efficiency, rather than the output and cost of an entire power generation site. VAWTs have an inherent unit inefficiency when compared to individual HAWTs, but because the VAWTs can be clustered in a tighter configuration with more units on a given acreage, the power produced per area will be higher. The HAWTs have a problem with turbulence when placed close together, while the VAWTs can benefit from a “flocking” effect that amplifies the individual turbine efficiency.

    From a systems perspective, considering the cost of real estate, transportation, construction, and maintenance (generators at ground level are easier to maintain), I have a subjective suspicion that a careful study would favor the VAWTs.

    1. Those studies have been done actually. There is one recent study that indicates with a very specific type of vawt in a very specific configuration at a specific wind angle then it is possible to have an effect similar to the v of geese flying through the air. When those stars align, the theoretical output is greater than a set of hawts. Note all of the caveats and the lack of real world testing however.

      1. Pat Kelley · ·

        Note that your emphasis is still focused on efficiency of conversion of wind energy to electrical energy. A real systems analysis takes into account all of the development costs, which still haven’t been rolled into the assessment.

  6. Michael · · Reply

    I agree with your main points, but I think your overall attitude is detrimental to the growth of innovation. If this planet and our culture is to survive (literally) we need as many energy generation solutions as possible, so we must continue to try new things, and/or rework old ideas with new technology.

    1. I disagree obviously but can see where you are coming from.

      It’s important, in my opinion, to contrast incremental with disruptive innovation. Wind energy technology is mostly mature and is seeing as a result substantial incremental innovation in coatings, height, blade profiles, business models, supply chains and construction techniques. These are responsible for driving the price of wind energy down to the point where it is cheaper than anything except shale gas, and they are doing it on the most appropriate technology framework as proven by testing and real word experience.

      Disruptive innovation might come from a new wind harvesting technique, but it is much more likely to come from a completely different technology. For example, if cheap fusion is ever perfected, this would be very disruptive to wind energy.

      My annoyance with these also ran technologies being dusted off and announced as the next great hope is that this typically does two negative things:
      1/ supports the idea that there is something substantially wrong with wind generation today, feeding into anti-wind campaigners’ campaigns
      2/ trivializes the extraordinary incremental innovation still ongoing

      Of course, innovation is a very poorly understood subject with most people assuming a new gadget is innovation.

    2. TIMTIM · · Reply

      Michael argues the logical fallacy of ‘argument from adverse consequences.” I can not prove that it works, but failing to agree with my argument will have the dire consequence of preventing innovation.

      1. Michael · ·

        When the topic is that of investment advice that could be viewed by a number of different people, thus steering the course of opinions and technology growth from the public and private sector in a negative direction, it very well could have dire consequences in the real world. Not a fallacy. This planet is not sustainable.

  7. […] Published by Barnard on Wind. View the original article.  […]

  8. AeroFox · · Reply

    Although, I can understand where your are coming from on your claims about innovation-items 1 and 2 in last comment, I can’t help but disagree. New designs, hype or no hype, can co-exist with traditional or conventional design (3 bladed HAWT). I think the “don’t feed the anti-wind crowd” may be paranoia. Despite the charlatan cries from the “anti-winders” wind has grown globally (Big and Small). New research on “anti-wind” folks essentially equates them to “conspiracy theorists” and other crack-pots (see that should be under psychiatric care. Machines constantly improve over generations and that’s what competing designs or other designs highlight-the flaws in the conventional design. it’s a machine after all-they aren’t perfect-don’t take it personally. Some non-conventional designs may have a specific niche or application (ducted, VAWT). In any event, no challenging design, has replaced the 3 bladed HAWT. Eventually, another design may do so or may co-exist. Technology is usually not disruptive until it is at its most mature point in its life cycle (i.e Big Wind), not at a prototype stage. Either way, we all benefit if COE drops comparable to fossil fuels (NATGAS). But at 400ppm (Mauna Loa GHG levels), should we really care about design preservation? Deploy all RE machines as fast as possible (IMO). We don’t have much time to count pennies.

    1. Michael · · Reply


    2. Matt · · Reply

      I may be wrong, but more than anything I think Mike is trying to emphasize that there are a lot of shoddy operators out there looking for gullible victims to rob. Personally, I’d read this article as: “If you aren’t absolutely certain of what you are doing, don’t invest in technology which makes extraordinary claims.”

      1. Thanks. The comments have led me to realize that more of a diversion into disruptive vs incremental innovation, invention vs innovation and the wisdom of Christensen and Raynor is required, but until then your comment will do nicely.

  9. Great article,

    I’m actually creating a project to work with inhabited remote stations, which you agreed, are the only places where VAWT are useful or can compete.
    To start I chose my provider (thinking on urban environments), UGE, because of aesthetics, for me their designs are compatible with architecture and cities where wind tends to be irregular.
    They are as you said, generating sculptures and their are used to shown a public commitment to green energy.

    That is the catch but then I realized that our market does not have the support and enough money to pay, so we need to exploit an industrial market, whose production facilities are located in remote land without any road or grid.

    Thanks to your article I could realize that the project shall not be pushed away from that niche.
    Remote stations.


    1. I’m very pleased that my post helped you think clearly about your market and business model. Thanks for the comment and good luck with your business.

  10. It is highly likely, based upon reports from Sandia Labs (floating wind technology) and Garrad Hassan (on VAWT and floaters from Europe’s largest renewable energy consultancy, part of the KEMA-DNV and Germanischer Lloyd group) that VAWTs placed upon floating units in water depths as low as 25 m will be the future of offshore wind. The current status quo 3-bladed aircraft propellor HAWT’s will disappear eventually. All onshore wind turbine sitings should be phased out rapidly as these will become unecessary. The most recent floater comes from MITSUI-MODEC. This could represent the “beginning of the future” for offshore wind floaters. The 1st serious player development, with intense Japanese Govt. backing and support post-Fukashima decision. This what it looks like at present and MODEC will deploy this at the end of 2013. They (MITSUI and the Japanese Universities) have been working on floaters since at least 2006 and have published a fair bit already, although not the interesting stuff which they do not want to fall into the hands of the Chinese! (or anyone else probably).

    The MITSUI-MODEC design, which has been accelerated hugely since Fukashimi, together with NENUPHAR in France are the leaders in VAWT floaters at present:

    MODEC are of course a big oil & gas Contractor organisation. Frankly, I do not like either of the Darrieus turbines shown here (3 blades, too many struts, just like the Windspire I saw rattle itself to pieces once, and I do not know what they have done with regard to resonance assessment and control or vibration (nothing?). Excessive vibration and bearing failures are what killed VAWTs in the past.

    Chris Golightly
    Offshore Renewable Energy Consultant
    Dr.C.R. Golightly, BSc, MSc, PhD, MICE, FGS.
    Geotechnical and Engineering Geology Consultant
    Rue Marc Brison 10G, 1300 Limal, Belgium
    Tel: +32 10 419525 Mobile: +44 755 4612888

    Linked In:

    1. Thanks for the detailed response Chris.

      I am much, much more optimistic about the future of HAWTs for offshore and much less optimistic about VAWTs actually being of value in that area than you are. The Sandia material I’ve seen — and referenced — is merely dusting off 20 year old research and doing an initial assessment to see if the trade-offs might finally favour VAWTs in this instance. Sandia’s $1.4M investment is hardly going to change the industry, but I am watching this space to see how it plays out. I’m certainly not ruling it out, but as I look across the full system of wind energy from cradle-to-grave, I see much more economic likelihood of HAWTs existing supply-chain being a deciding factor if VAWTs actually managed to achieve technical equity with HAWTs in this space, which is far from proven yet. Innovation is about more than just the tech, after all.

      As for phasing out onshore HAWTs, I have no idea why you would think that is a likely or reasonable scenario. Your comments and materials don’t support this rather extreme suggestion. The world needs a ton of carbon-neutral energy, and onshore wind is an excellent and economically viable source of it. Regardless of anything else, the cost of constructing and maintaining onshore HAWTs is always going to be lower than offshore, so while the economics may shift a bit, they will not eliminate onshore HAWTs.

      If offshore VAWTs do become the dominant offshore generation technology, they will become another technology, not a displacing technology for onshore generation of various types in my opinion.

  11. Michel Gingras · · Reply

    Do remember that by publising the failures of alternative wind technologies, we are effectively killing any real hope in improving future conceptual development in the Industry. Also be reminded that the community is still debating how aircraft fly. Stunning, but absolutely true.

    1. I disagree. By pointing out obvious non starters we free up fairly limited research and development dollars for inventions with real promise.

      As for debates about aerodynamics, please share references.

  12. Sunflower · · Reply

    Re SAPHON Energy:
    I came to same conclusions:
    a non sense. not feasible. To beat Betz limit, is like to exceed speed of light !!!
    IMO: charlatan at best, huuuge SCAM at worse.

  13. Michel · · Reply

    Sometimes we are led down certain technology paths because somebody up-front made an observation and jumped to a rash conclusion, which continues forward. Take for example when Ben Franklin established that current flows from positive to negative. We continue to use wrong theory, and have made accommodations for the science, so that we can understand it the wrong way. BTW…electron-flow moves from negative to positive.
    On another similar note, the aerodynamics community has determined that there are only two types of air pressure…dynamic and static. Where dynamic pressures mirror a ‘left’-energy scenario and static pressures mirror a ‘center’-energy scenario. So what’s on the ‘right’?
    It seems we’ve just begun to study aerodynamic elasticity, and are still scratching our heads. Dudes! Bet you all a Buffalo Nickel, we’ve been working with our blinders for far too long. How can the Benz limit be established, if it’s possible we’ve got the base-rules wrong? And no….there is no prior art..because we aren’t innovating any more. New game.

  14. Graham · · Reply

    What I find interesting, is that the author appears to have a closed mind against innovation in wind generation. He has made up his mind that that the only alternatives to a three bladed turbine are other types of turbines (that he probably rightly claims are less efficient).

    What I see is missing, is a consideration of alternatives that convert wind energy into electricity without need for a turbine. I won’t go into it here, but I once thought I had an original idea that might do just that. Then I found that some kids in Asia had actually built a prototype as a high school science project! It turned wind into enough electricity to light an incandescent bulb and it had no turbine or other rotating parts.

    We need to start thinking outside the box when it comes to wind generation.

    1. You mean like the Ewicon which I assess in my post on good and bad bets ( and in detail here on Quora ( Or the Humdinger which uses harmonics in tight belts assessed her on Quora ( Or swaying stalks (

      You seem to think that examples missing from this particular post of even less likely forms of wind generation means I haven’t looked at them. My apologies Graham, but the missing perspective is yours.

      1. Graham · ·

        No, none of those is anything like the example I cited.

        What comes across here, is that you are the all knowing person and nothing anyone esle says or does is of any value.

        This is a subject that interests me, but I think I have come to the wrong place.


      2. My point is that virtually every approach to generating electricity from wind energy has been exhaustively assessed already.

        Three blade horizontal axis wind turbines out compete all of them on all of the metrics that matter. It’s not my opinion, it’s reality.

        Feel free to explore alternatives, but pay close attention to prior art and failures. Wind energy has been being harnessed for thousands of years and enormous numbers of smart people have looked at it.

      3. Pat Kelley · ·

        Mike, I appreciate your extensive review of all the “creative” wind technologies and their shortcomings. I would point out that the Alteros concept could be accomplished without relying on helium. Hydrogen is cheap, with better buoyancy. Since the concept carries no perishable cargo, all of the Hindenburg scare nonsense would be easier to brush off. Even ammonia is a potential alternative, as it’s already used as a helium alternative for weather balloons, having about 70% of helium lift capacity.

      4. Thanks for the info on ammonia, I wasn’t aware of that option. I did a more complete analysis of Altaeros on CleanTechnica here: I deal a bit more with the hydrogen point and concerns about shipping Helium apply to ammonia too. Regardless, it’s the poor generation and low ability to scale that seem like the killers to me.

      5. Pat Kelley · ·

        I agree with the scalability issues, and the dilemma with airspace restrictions. There are portable ammonia generators that can be set up wherever there’s a supply of natural gas, so there are some locations (like Alaska) where the shipping issues are of less concern. Helium comes from only a few wells, and there’s no alternative to shipping in extremely high pressure tanks. Ammonia changes state to liquid at about the same pressure as propane (200 psi), so containers are much lighter and smaller, since the fluid density is much higher than helium or hydrogen gas..

      6. Interesting and good to know. Thanks!

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