windmill for only 1.5 volts

Discussion in 'The Projects Forum' started by Lightfire, Feb 8, 2011.

  1. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010

    I am trying to build a windmill which makes 1.5 volts. And as per for wattage, I don't know if how many watts. But I think my windmill is just for lights and some DC motors.

    P.S. My windmill is just for testing purposes only that's why it's rated as 1.5 volts.

    Here we go.

    I found this somewhere;

    How much is motor are?

    What items do I need to build a windmill (which is rated as 1.5 volts)

    How many power can the power last long? (Or it can lasts until the windmill starts to not to rotate anymore)

    As usual, DO I am wasting money for that????

    Last edited: Feb 8, 2011
  2. Wendy


    Mar 24, 2008
    Guess what. I waste a fortune on parts. Welcome to the wonderful world of electronics as a hobby. :D I'm thinking a small electric motor, right? You might get some usable power, but mostly you'd be learning something new.
  3. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010
    Huh??? :d :d :d
  4. nerdegutta


    Dec 15, 2009

    Senior Member

    Jul 1, 2008

    Snip from above link: In the past, we've built anemometers based on small DC hobby motors. While these units did work, there were problems to overcome. Most hobby motors use cheap bushings instead of bearings. The bushings tend to fail rather quickly, since they are not designed to withstand the forces put on them in an anemometer.
    I don't mean to be picky here but the term "bushing" is constantly misused, even in dictionaries. What those motors have are, in fact bearings, and if they're properly maintained and lubricated they'll out live you! One of the other things I do, besides electronics, is machine shop. I moderate 6 forums dedicated to the history, restoration and maintenance of antique South bend and Logan lathes. We have members that own SB models made at the turn of the 20th century. Many of them have the original, Brass, Bronze and believe it or not sleeveless Cast Iron bearings in the head stock. Admittedly, unlike sealed ball bearings, they are not maintenance free.
  6. wayneh


    Sep 9, 2010
    Well, the easy part is voltage. For any windmill, voltage will be proportional to the speed of rotation of the mill, so there is no such thing as a x-volt windmill. It's the wattage that makes things challenging, and you need to estimate how much wattage you need. Otherwise, you - like many others before you - will likely be disappointed when you discover how little power your wind turbine makes. You'll have a lot more fun if your expectations are not so much higher than reality. The more you can specify what LOAD you want to power, the better your results will be.

    Just as an example, the generators for bicycle lighting, the "bottle dynamo" kind that run by friction contact to your tire, are designed to generate 6W. They spin more quickly than a typical windmill, and suck power out the rider. If a rider is able to generate 100W, a 6W "drag" is a noticeable energy cost. My point is that it not easy to generate even 6W. Those "hub dynamos" are considered the latest thing in bicycle lighting and I've heard good things about them. The only drag they generate is due to the power they generate (not friction), so they are much less inconvenient to use.

    One problem in aiming for such a low voltage is that you will LOSE a similar amount of voltage rectifying to the alternating current made by a generator into DC, if that is part of your plan. This is because of voltage drop of ~1.4V across the rectifying diodes. So half of the power you generate will be lost in the diodes and half made available for other uses.