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New Bladeless Design for Wind Energy

  1. May 18, 2015 #1
    Sounds pretty good:
    http://www.theverge.com/2015/5/16/8...s-wind-turbines-shake-to-generate-electricity

    I like this particular idea a lot. With no blades, these take up much less space, and the claims about them being 50% less expensive to make, and lower maintenance, seems completely plausible. They would be a good design for powering cold outposts that are frequently overcast, but windy. The thing I would most like to find out about them at this point is how they're affected by snow. Ever since I experienced Minnesota, I've been mulling over the idea of a device to generate extra electricity from the cold winter winds, which is when you need it the most there. The trouble with every idea I had was clogging from snow and ice build up. These look like they'd shake it off.

    I am not sure the claim they "only" capture 30% less energy than a bladed turbine is plausible. I have the feeling, 'On a good day, they can capture as much as 10% of a regular turbine,' would have been more accurate. Depends on how they're comparing them. Regardless, they strike me as the sort of design that would become cheaper and cheaper to manufacture the longer they had to work out the bugs and streamline the process.
     
  2. jcsd
  3. May 18, 2015 #2

    Ryan_m_b

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    The lower maintenance seems quite interesting. I'd like to see some proper figures of how much energy they can produce and what a farm of them could do given minimum separation distances. I half-hope that this could get round the weird Nimbyism a lot of people here in the UK have because they find the spinning turbines ugly. Conceivably these could be any colour, paint them brown and stick a few fake branches on them and they'll blend right in with the view.
     
  4. May 18, 2015 #3
    Yes, they look intriguingly simple.
    Absolutely. The problem with most of these inventions is that the inventors grossly over-estimate the efficiency. The things works, but ends up not being worth the effort to implement.
    Hah hah! But then you might get complaints about an introduced species.
     
  5. May 18, 2015 #4
    In the long term, this is the future of wind power. They are cheap and look nice. They work similarly to trees swaying in the breeze which means they are environmentally sound.

    In the short term, no numbers means all hype. The claim of no moving parts is unrealistic. The poles are supposed to vibrate, which means motion. Further vibrational movement is typically more damaging to equipment than circular movement. Permanent magnets lose magnetism when moved through fields repeatedly, and electromagnets need power. Their performance in storm conditions wasn't mentioned which can't be a good sign.

    There are solutions to all these problems, but since the promoter didn't address them, I'm guessing he hasn't found them yet.

    I hope they can get them to work, but I doubt they can.
     
  6. May 18, 2015 #5
    Very good point. That didn't occur to me.
    From ferroceramic magnets forward to rare earth types, this is not a problem. These kinds hold their magnetism beautifully and were engineered with that issue in mind. Loss of magnetism was only ever an important problem back in the days of high carbon, hardened steel magnets.
    Not necessarily. There is the phenomenon of the "self-exiting dynamo".
    http://en.wikipedia.org/wiki/Excitation_(magnetic)
    Yep.
     
  7. May 26, 2015 #6
    This device seems to rely on vortex shedding to keep it wiggling. Does this imply a very narrow range or Reynolds number?

    On top of that, do you need to go around whenever the wind conditions are optimal and give them a kick-start with a stick?
     
  8. May 27, 2015 #7

    rollingstein

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    How are they actually generating energy with a small amplitude vibration motion? All the efficient, commercialized generation technology I've known is rotational.

    To put this in perspective, I don't think they even have a one kW prototype demonstrated in a on field test. Too early for all the hype. I'm very skeptical that the capex scales favorably. A typical wind turbine is in the hundreds of kW range.

    If they try and scale this up the foundations needed to resist the impact / stress of those oscillatory vibrations would need to be quite robust?
     
  9. May 27, 2015 #8

    QuantumCurt

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    I really like this idea, but some questions persist. It seems to me that there would be seasonal fluctuations in their generation of energy. In colder temperatures, the towers are going to be less flexible, meaning a smaller amplitude of oscillation. It seems plausible to me that such a fluctuation could exist. I wonder if compensation for such a likelihood has been factored in. As previously mentioned, it seems likely that snow and ice buildup would have an effect on these as well, although that could easily be addressed with a simple heating element to keep ice from building up on the surface.

    The fewer maintenance needs is appealing, but comes with a drawback: jobs would be lost. The regular maintenance of wind turbines has resulted in the creation of many jobs. A lot of people in my area have gotten certified to work on wind turbines in the last ten years or so, and it's become one of the better jobs around here. If the current wind turbines were replaced by these, it doesn't seem likely that all of these people would be keeping their jobs.

    One potential large bonus I can see is that I think people would be less resistant to these than many of them currently are to wind turbines. Personally I think wind turbines look awesome. Not only for the engineering involved in them or the fact that they generate clean electricity, but I also find them to be quite aesthetically pleasing. This is a personal opinion though. Not everyone will agree. However, one of the complaints that I've heard most about conventional wind turbines is that shadow flicker can cause epileptic seizures, which is a legitimate complaint in some cases and an empty point of argument in other cases. As the blades spin around, they cause shadows to periodically flicker. In some cases, poor placement has led to these shadows being cast into peoples' houses. I think this is a very valid complaint, but is easily resolved by proper offsetting to avoid it. Another complaint is that the turbines often interrupt the flight paths of migrant birds. Turbines are located such that they take advantage of naturally occurring air currents; the same air currents that birds take advantage of when they migrate. There have been many instances of birds being killed after flying into the blades of a turbine. I think this is in some respects a valid complaint, but personally I think the sacrifice of a few ducks and geese is well worth the cleaner energy that is produced. And the people making these complaints often don't consider how many birds fly into the windows of a typical skyscraper every year.
     
  10. May 27, 2015 #9

    jim hardy

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    Work = force X distance so if the displacement is small the forces must be large.
    Well, given that tall tower with generator at its bottom they sure have plenty of mechanical advantage.
    I'd guess they use some sort of wobble plate to vary reluctance and modulate a magnetic field.

    Extracting energy will damp those 'resonant oscillations'..

    Call me a curious skeptic..... If they can do a megawatt i know somebody who needs a couple hundred of them.
     
  11. May 27, 2015 #10
     
  12. May 27, 2015 #11
    Yes, it would be nice to have an explanation of exactly how the generator part works, but you are right that this is a long lever and a small force at the top end will be amplified a few times at the bottom. That said, though, you're also right about the damping.
     
  13. May 27, 2015 #12

    rollingstein

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    Me too! Intensely skeptical. Their first 10 feet tall unit is designed to generate 100 Watts.

    Other than aesthetically pleasing designs there's not much hard data on that website to chew on.
     
  14. May 27, 2015 #13

    rollingstein

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    I want to see how efficient they can make this transformation.
     
  15. May 27, 2015 #14
    I don't foresee a big problem making them efficient, at least to reasonable rates (~50%).

    In air magnetic fields are poorly understood at this point. There's plenty of science, but engineers have concentrated work in cores. They will need a good magnets engineer and those are rare at this point. I can foresee some design issues with EMF noise as magnetic fields go all higgly-piggly.

    There are lots of problems to solve and lots of work for engineers. :oldlaugh:

    We should push this technology as an engineering jobs program. :devil:

    That was sarcasm. I would never push an uneconomical project just to line my own pocket. Still, if GE has a bunch of engineers sitting on their hands, there are worse slot machines needing feeding.
     
  16. May 27, 2015 #15

    anorlunda

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    Count me as a skeptic along with others in this thread. But I disagree with Jim on that point. A 100 watt DC generator with low complexity, low maintenance would be welcome in many third world locations. It could power LED lights, and charge cell phones at night when solar panels don't work. But its cost would have to be comparable to a 100 w solar panel, something less than $100.

    We need to think of electric power in terms of the law of dimishing returns. The very first increment from none to some is very valuable. That is very different from adding another increment on the top of a previously developed society. Considering the cost benefit curve, the difference in slope between the first and last increments could be on the order 10^4.
     
  17. May 27, 2015 #16

    rollingstein

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    Diesel / Gasoline operated generators seem ubiquitous in whatever parts of the third world I've seen. Some very poor & backward regions too. Besides the expertise to repair & maintain them seems quite accessible in rural third world mechanics.

    Although generators can be finicky they also take quite a lot of battering very well. Parts can be poached off vehicles etc. I've seen lots of improvisation. The technology overlaps a lot with vehicles. The basic technology is largely unchanged for decades so the penetration & knowledge base is high even in remote areas.

    Any device trying to supplant them will have a very high bar I think. I'm not sure I see the third world as a good market for a novel wind device.
     
  18. May 27, 2015 #17
    I agree the third world cannot support the non recoverable engineering costs of this technology. But in the long run this technology is little more than a pole and the cost should be minimal; even minimal enough to out-compete generators.

    Getting from hype to mature technology is a big, expensive problem.
     
  19. May 27, 2015 #18

    rollingstein

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    A pole & pretty substantial foundations?

    A 42 feet tall pole intentionally optimized for vortex shedding. I'd be curious to see what sort of anchor forces they expect in a gale.
     
  20. May 27, 2015 #19

    bhobba

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    For me its a no brainer. Here in Australia we have had a number of investigations about the health effects of the noise regular turbines make. That they make no noise has a huge political advantage even if the health effects of the noise is exaggerated - people will always, if their is the slightest hint of health problems, work long and hard to scuttle it.

    Thanks
    Bill
     
  21. May 27, 2015 #20
    Complex parts near the ground +
    Simple construction +
    Lower efficiency per unit -
    Higher efficiency per unit area ?+

    Mechanical durability does seem scary. But I can imagine that physics of using EM fields to stabilize more of a "vibrating" mechanical system, while siphoning off the work done against the stabilizer - could turn out to just be about clever circuit design.
    Existing wind turbine generators use some type of magnetic field generating system, and it's at the top of a big skinny pole.

    There is a large wind farm near my father's farm. Two problems that mean NIMBY for me.
    Low frequency noise. It is there, and it get's to you (it does me anyway). And I suspect it varies in a high density field in a way that is non-linear. I'd be curious if these are worse or better in that regard.

    For some probably idiotic reason there are huge FAA type signal lights on top of each one. And they all blink on at once. We pondered and pondered how this is achieved, and the why.. but the effect at night is... frankly hellish. I couldn't live with it. Good only if you wanted read a book to Satan, three words at time.

    Those concerns aside (problems that need to be solved), I am gung-ho for wind power, and re-newables in general.
     
    Last edited: May 27, 2015
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