There 100's of cheap home built 50 to 300 watt wind turbines sold on eBay these days. Well, BEWARE!! The chances of you getting much more than 20-50 watts from one of these units is rare at best. Plus if you wish to use one of the many Grid-Tie plug and play inverters, you will automatically loose about 30-50 watts just to run the inverter!! So your left with what now??? I plugged in one of the 250 watt 12 volt wind turbines purchased on ebay with the gearmotor on it, to a 300 watt inverter with 10-28 volt input specs. The turbine rarely even had enough to power the inverter to the point of allowing the green Inverter light to come on, even in 15-20 MPH winds the red light would be on sometimes, telling me that there was not sufficient power coming in yet!! These turbines are fine if you just want to charge batteries, but not so worth while for supplementing your home grid. Solar Panels are more efficient (but only on sunny days). Also, do not bother with the cheap gear motors or cheap gear driven PMA's, they will not last long! And they are very very noisy, your close neighbors will complain!! As far as paying for themselves... Well I seriously dought they will last long enough to pay their way. Once they get worn some, they almost sound like a siren! I have been purchasing some of the cheaper units from eBay and am writing this as my personal experience and hopefully helping others with their decisions. Have fun!!!
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