A key element of his system is the wind electric generator, and there are many options that vary in their complexity and the type of output. Generators can be continuous or alternating current (AC) and brushed or brushless rotors and possibly permanent magnet or stators.
One option, although the complexity of the design or your own wind turbine from scratch. It is even possible to use alternators car, but they generally require some type of mechanical transmission, because they are designed to run much faster than a Typical wind. A permanent magnet alternator using permanent magnets on the rotor and has the advantage of requiring no brushes, so the only parts subject to mechanical wear of bearings. For easy connection directly without gears, a very popular solution is to use a magnet permanent surplus DC (PMDC) motor.
Although PMDC motors can easily be used as generators, which were not really designed to do and be careful when choosing one for this purpose. Due to the loss of an engine operated for strain particularly, many RPM not produce the same tension when run on the RPM as a generator. For this reason, the best drivers to use to build your wind must have a high voltage DC and low speed. For example, a rating of 30V engine and a few hundred RPM would produce an output voltage of 12V for a useful system typical low speed wind turbine.  Â
The next thing to consider is the output current. An engine using a thin wire in the windings will be smaller and lighter, but the current is limited and the greatest losses. More power = more power for a given voltage and remember that when is used as a generator engine does not provide the power that the engine is worth.
In short, when the election of a permanent magnet DC (PMDC) motor for its use as a windmill, a search engine with a higher voltage than you want your output, low speed and rated high current. Selecting Correct this key component will have a major impact on the overall efficiency of your home built wind, and should be chosen carefully.
