Windmills-Free Electrical Energy

     Windmills are a great way to produce free electrical power.  There are so many designs from complex to very simple.  http://en.wikipedia.org/wiki/Wind_turbine  There is also a wide variety of types of windmills.
     The most common is the wind turbine.  The wind turbine comes in two different varieties; horizontal axis (HAWT) and vertical axis (VAWT).
     A horizontal axis wind turbine sits on top of a pole and looks like an airplane propeller.  The central axis of the propeller travels into a generator.  The turbine must be faced into the wind to work.
     A vertical axis windmill sits directly on top of a pole but built more on the fashion of a hollow washing machine tub with the axis coming straight out of the support pole into the generator.  The advantage of a VAWT is that it doesn't have to be faced into the wind.  http://centurionenergy.net/types-of-wind-turbines
     Of course there must be batteries to store the energy produced by the windmill.  Depending on the generator output determines the number and size of batteries.
    The simplest windmill I have seen was made from a car alternator from the local junkyard with a house fan attached.  This forms the horizontal type of wind turbine.  Make sure and mount the alternator on a set of bearings so it can rotate into the wind.  This system requires two car batteries and an electrical inverter to change DC to AC power.
      It is best to keep a power meter on the batteries as too much charge can cause the batteries to explode.  A voltage regulator will shut the incoming power off to prevent this from happening.  http://www.reuk.co.uk/Interconnecting-Batteries-for-Battery-Bank.htm