I want to build 2-3 small wind generators for fun and learning. Plan to use the energy produced to preheat water for my hot water heater. Tap water during the winter drops down into the 40's during the winter. Maybe later I would like to tie them together add batteries to run one 110 volt 5K air conditioner, power permits.

What I would like to know is how to chose a DC motor. Do I go by the amperage, RPM, Voltage or What? Looking for best output if the wind blows. I goggled a lot, found more of Spam, than good information.

Welcome to the forums, kb. As far as which motor is the best for adapting to use as a generator on a wind turbine, there is no single right answer, except that DC motors aren't what you want unless you just have no other choice. I can tell you one thing for sure, though. The majority of the time you will end up spending less money, while producing more power, by buying a pre-built turbine.

Check out this link for recommendations of both pre-built turbines and DIY turbines, and for a decent discussion on what you seem to be interested in doing, we just discussed the topic in this thread about a month ago.

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On this site, 99.999% of all underlined words are links.

A watt saved is better than a watt generated, since it always costs less than 10% as much, and can cost as little as 1%.

V=volt, A=ampere, Ah=ampere hour, Wh= watt hour, VOC=open circuit voltage, ISC=short circuit current, VMPP=voltage @ max power, IMPP=current @ max power, BTW=by the way, your=belongs to you, you're=you are, too=in addition to, two=1+1, to=towards

Also, since you're interested in heating water to begin with, you'll definitely want to watch part one, and part two of this video. That would be be a much cheaper and easier way to get started heating your water with the sun.

You'll also most likely be interested in both this video and in this one. See, heating things is what the sun does best, and it's actually considerably more efficient to just skip the intermediate steps, and get to the heating immediately.

edit: Oh, and a 5,000 BTU air conditioner will use 550-600 watts of electricity while the compressor is running, assuming it's one of the new, efficient models. That means you'd need to be producing 1,100-1,200 watt hours per hour that you wanted to use the AC, which is an awful lot of power.

__________________
On this site, 99.999% of all underlined words are links.

A watt saved is better than a watt generated, since it always costs less than 10% as much, and can cost as little as 1%.

V=volt, A=ampere, Ah=ampere hour, Wh= watt hour, VOC=open circuit voltage, ISC=short circuit current, VMPP=voltage @ max power, IMPP=current @ max power, BTW=by the way, your=belongs to you, you're=you are, too=in addition to, two=1+1, to=towards

Thanks for the reply. Think I'm going to jump into this and get some solar for lighting and use the wind for supplement.
thanks
kevin

Kevin, that sounds great. That's what wind is good at: being a supplement to solar. Wind is most reliable during late fall and winter, which just happens to be when solar output is the lowest. I think you will be very happy with your decision.

I think you will be much happier, though, if you'll spend considerably more on the solar than on the wind. Here's why. Solar will give you output 365 days per year, as long as they aren't cloudy. Less in the winter and more in the summer, but some output is 1,000 times better than no output. Wind is the opposite. You either get more output than you'll know what to do with, or very little output at all.

That's why a small, inexpensive wind turbine (which do in fact have to be repaired/replaced much more often than some people would have you believe) is the perfect supplement to a large solar installation, and a large, expensive wind turbine is not the perfect supplement to a small solar install. If you have any questions about either the solar or the wind installation*, we'll be happy to answer them. Good luck.

*Please, do yourself a favor, and get a 40+ foot tower to begin with, and a 60+ ft if you have the money and the room.. The difference in annual output between a 25 foot and a 40 foot tower is roughly double in favor of the taller tower, and that's with the small 200-400 watt turbines. With a 2kW-3kW turbine, a 60 ft tower isn't nearly tall enough. Seriously. Good luck.

edit: You might want to read this story from an actual owner: http://www.earthbilly.com/wind_turbine.htm He actually tried out two different tower heights.

__________________
On this site, 99.999% of all underlined words are links.

A watt saved is better than a watt generated, since it always costs less than 10% as much, and can cost as little as 1%.

V=volt, A=ampere, Ah=ampere hour, Wh= watt hour, VOC=open circuit voltage, ISC=short circuit current, VMPP=voltage @ max power, IMPP=current @ max power, BTW=by the way, your=belongs to you, you're=you are, too=in addition to, two=1+1, to=towards

i was willing to purchase a motor. And i like the way you explain the method....