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Alternative Energy Windmill Ideas

  1. Oct 30, 2007 #1
    Here's the problem...

    I am to build a simple windmill (small scale) to lift an x amount of weight twelve inches above the base plane. The required amount is to lift 200 grams, 12 inches in 2 minutes or less. The materials are to be mostly recycled; however, I am alotted $15 to buy any new materials needed. The windmill will be sat in front of a standard box fan to turn the mill.

    The basis for my idea is this:
    1. An abundance of blades, with a decent amount of pitch. Material not yet known
    2. To lift the weight, I will pull a small vehicle up a ramp that will eventually become 12 inches high.
    3. The windmill part will turn a drive shaft. This drive shaft will be connected via belt to another drive shaft. This shaft will have a string that will wrap around it to pull the car up the ramp.

    What I wanted to know is...
    what is the basis to have a successful windmill? Is more blades or less blades good? Minimizing air unaffected going through is key right?

    Could anyone give me some alternative ideas that would succeed?
  2. jcsd
  3. Nov 4, 2007 #2
    Have you put any thought into the use pulleys?
  4. Mar 1, 2008 #3
    Dear friend,

    We can get the Power generated from a wind mill using the formula p=1/2dAV^3

    where d is air density in Kg/m^3, A is the swept Area again depends on Blade Dia, and v

    is the wind speed in m/sec. The blade has to be aerodynamically designed and

    balanced and I think nothing related to no. of blades.
  5. Mar 1, 2008 #4
    Your input is great, rsrajeesh, but jstew posted his question nearly 4 months ago, to put things into perspective. Try helping out people who have more current questions - people who don't get their questions answered within 2 weeks generally won't ever look back on them.
    Last edited: Mar 1, 2008
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