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A simple DC generator can be made out of a car alternator. These little jobs generate AC, but there is an internal rectifier and regulator that makes it into a constant (sort of) 12-14V DC. And just as your car engine changes speed from maybe 500 to 5000 RPM while driving, it will work over a long range of wind speed. The only problem is that a normal alternator (like my AC Delco) will only put out 80-100 Amps. Some simple ohms law says that
Power = Voltage x Current
so best case
Power = 100 x 14 = 1,400 Watts
So even a car generator can give you 1 or 2 Kw. Good idea for a backup at the least! Only thing is you only have DC, 12V, and most appliances need 120V AC. They sell power inverters that let you do this conversion, but the higher the wattage the more expensive. I think a 1 Kw unit is pretty bulky and a few hundred bucks, but hey, you can run almost anything then.

Offered by Rob.

Use a quantity of 12 car alternators wired in series and all driven from the same adjustable pitch propeller. Build this by use of belts, bicycle chain, or gears to drive all alternators at the same speed off of the same slow speed propeller. The 120 Volt DC output can be used directly to produce resistance and diode type lighting to grow our food and for task lighting. Many other appliances can also run on this DC 120 volts. 12 x 12v batteries are wired in parallel and are being charged all the time to help stabilize the voltage as demand changes. A high voltage DC inverter is used for the small amount of AC that is needed.

Adjust the propeller pitch to regulate voltage as you have suggested. It may be possible to design it to not need the 12 volt car regulators. I have found the most common alternator to be 55 Amp. Thus the result would have a maximum of about 6,600 watts to 12,000 watts. This depending on whether a cheap or more expensive alternator is used. Rebuilt alternators are relatively inexpensive. The use of 120 Volt instead of 12 Volts allows for smaller wire to be used.

Offered by Mike.