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B Wind Turbine price/energy

  1. Mar 25, 2017 #1
    I was wondering if placing something (cheap) in front of a wind turbine to redirect more wind towards it would be worth it or should I just place more (expensive) turbines?
     
  2. jcsd
  3. Mar 25, 2017 #2

    anorlunda

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    You should assume that designers of wind turbine farms have explored every possible way to make things more efficient. If they don't use it, then it doesn't work or the cost is more than the benefit.
     
  4. Mar 26, 2017 #3
    Provide a drawing of your ideas. How would it deal with the fact that the wind changes direction?
     
  5. Mar 26, 2017 #4

    CWatters

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    They do sometimes place objects in front of turbines to deflect the air...... Turbines are frequently placed on natural ridges that deflect air up into the turbine.
     
  6. Mar 28, 2017 #5
    I guess that you are imagining something like a giant cone that diverts a larger cross section of air into a smaller cross section where a turbine is.
    You should consider just how large wind turbine blades are. A blade might be 116 ft long. They sweep over a huge area of air. But since the blades are relatively narrow, they require less resources to build than what is needed to construct something the size of the area that they sweep. If you consider some kind of "air dam" that diverts air into the swept area of a turbine, it would have to be huge. Since it has to actually cover the surface area, unlike the turbine blades, it would take a huge amount of resources to build.
     
  7. Mar 28, 2017 #6

    anorlunda

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    Not only that, but it needs to swing with the turbine to always face the wind direction.
     
  8. Mar 28, 2017 #7

    CWatters

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    It's not clear to me that a funnel of diameter D feeding a turbine of diameter d would be better than just a turbine of diameter D.

    I addition it's easy to feather a turbine when the wind gets too strong.
     
  9. May 18, 2017 #8
     
  10. May 18, 2017 #9
    I am currently building my own wind turbine.
    I am using a funnel design to increase air speed.
    There seems to be a lot of different answers on this subject if it really works. Does anyone know for sure?
    I am also trying to use the exhaust air without creating back pressure in another funnel and reversing wind 180 back to the other side of the turbine.
    I am in the early stages of fabricating and would like to have some input.
     
  11. May 18, 2017 #10

    anorlunda

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    Why do you suppose that the big commercial wind farms don't do it like you plan?
     
  12. May 18, 2017 #11
    Thanks, but that's another question.
    This entire circle of wind energy is shrouded with a lot of opinions without any real facts or reasearch.
    If the wind farms have tried this I am unaware.
    Can you link me to a website that would show they have tried thus or even reasearched the possibialities.
     
  13. May 18, 2017 #12
    Better to invest in LNG or diesel generators. Petroleum products are going to be cheap and plentiful for the foreseeable future.
     
  14. May 18, 2017 #13

    sophiecentaur

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    An optimal turbine design for free air would be different for a design that works best in a 'funnel'. You could make things worse.
    Also, how were you expecting to steer any such funnel system? I see that using longer blades has already been suggested.
    Is that possible? In the end, you still have to remove the air that has passed through the turbine and that requires some Power, however you achieve it. I guess you could argue the fact that the turbines in jet engines use multiple stages as a support for your basic idea but, again, there is the steering problem, which is not present in aircraft propulsion.
     
  15. May 18, 2017 #14

    anorlunda

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    No and that's my point. Don't you think that if there was any reasonable way to do it better that they would have done it?

    In today's world, we have so many smart people that it is really difficult to have a truly original idea. I need to constantly remind myself that the reason I don't see my "original" ideas implemented, is not that nobody else thought of them but more likely that someone else thought of the idea and rejected it. If he documented the reasons for rejection in an email to his boss, I'll never find the email.
     
  16. May 18, 2017 #15

    sophiecentaur

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    The business of Aerodynamics is extremely complicated and not at all intuitive. Designing turbine blades and aircraft wings are very similar exercises. How many enthusiastic experimenters would ever have come up with the efficient wing designs on modern airliners? It's always fun to experiment but building a series of turbine blade designs is really not easy for the home constructor (unless you have a large 3D printer?) I think that using designs that have already been proven is the way to go. Photos of existing designs would give you a good idea of optimum pitch and aspect for the blades. (I'm suggesting a bit of industrial espionage.) Use the benefits of someone else's R and D.
     
  17. May 18, 2017 #16
     
  18. May 18, 2017 #17
    I am in the crane rental business and have help erect many wind turbines, so I see a d hear a lot.
    Maybe in high wind area you are right but I don't think so in low wind areas.
    I am actually building one no just talking about it!
     
  19. May 18, 2017 #18

    sophiecentaur

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    I'm not sure what your 'high wind area' comment was referring to in your quote from my post. Was it my comments about wings? But the same requirement for efficiency is there with wind turbines.
    To be fair, I have installed one. so I am not just talking about it. But it was out of a box.
    'Talking about it' is what theoreticians do a lot of. And they can be 'right' about a lot of things - and someone who builds something doesn't always get it to work in the way they hoped. A good bit of theory can prevent that problem. As you are in close contact with various designs of blade, it should he possible for you to take some useful measurements. What construction technique are you planning for the blades?
     
  20. May 18, 2017 #19
    Devil's Advocate:

    "If no one else is doing it, well then, it's not worth attempting. After all, there is no way that anyone could ever come up with an original, practical idea that someone else hasn't already come up with..."

    Except that's not true.

    :: soapbox on ::

    The Wright Brothers did not invent flight, wings, or the airplane - they invented a modification of the wing, and some other innovations that allowed flight to work well enough that it became practical after further refinements, and innovations. At the time, few people thought that manned-flight was even possible. Not bad for a couple of bicycle shop owners, eh?

    The "Wizard of Menlo Park" brought to the world light without fire - Mr Edison was considered a crackpot by many, because he announced that he was inventing the electric light before he had a working proto-type. While an open flame was the source of home lighting for most of his contemporaries, I would hazard a bet that you don't even know anyone who lights their home primarily from some form of oil or gas lantern. The list of failed proto-types was extensive, and impressive in it's scope of filament materials. One day, he tried Tungsten, and history was made.

    I am not a historian, and I haven't the rote memory to spout off a long list of people throughout history that came upon a revolutionary idea while they were struggling to perfect something that was considered by others to be impossible... but I assure you that the list is extensive, and covers (nearly?) every branch of the physical sciences.

    It's not always the destination - sometimes the journey is what matters, because it offers us an opportunity to choose a new path, when we have that "Eureka!" moment. (Which is another success story about an innovative way to measure the volume of an irregular solid...)

    Do not be intimidated by nay-sayers. Don't let ANYONE tell you that it can't be done, unless they can PROVE to you that it has been attempted, and there is documentation to look at, to understand WHY it failed. And if your idea is a variation, then it's up to you, not anyone else, to decide if the lesson of failure for their attempt applies to your idea.

    Sometimes the journey to failure teaches us lessons that lead to success in other ventures. If you are enjoying the journey, then just stick to it, until you see a better goal. There is no shame in tacking into the wind, when you have that Eureka moment.

    On the other hand, don't let yourself get lost in a project that has minimal opportunity of a short-term positive outcome. Long term projects have a way of consuming people, who later look back at their lives and wonder where the years went... In other words, don't forget to have a life, and enjoy your family and friends along the way.

    :: soapbox off ::
     
  21. May 18, 2017 #20

    sophiecentaur

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    That can be a recipe for wasting an awful lot of time and money. Repeating someone else's mistakes when one could have read about it and understood why it went wrong can be a pointless exercise. Life's too short to repeat past errors - unless you just like making things that don't work.

    For every Wright Brother or Edison there are thousands of people who tried things and failed (died). Also, you are quoting from the technological distant past. Early on in a field it is less difficult to make a breakthrough. Aerodynamics is a very technical subject and the probability of a kitchen table top advance is very low. Even if something happens to work a bit better, the experimenter will not know why.
    There is no need to be defensive when experienced people preach caution - I know there is a romance in the idea of 'proving everybody wrong' but those events are getting more and more rare as Science advances.
    If you pick your field of study, one can still achieve 'firsts', though. One day, a lucky(?) amateur astronomer may be the one to spot the asteroid that will wipe out the Earth.
     
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