I have an Ametek '30' on my Pedal Generator,
34 inch diameter crank flywheel .....2inch dia.
motor 1:17 ratio,with a full wave rectifier.
Charging 2 12volt batteries in series I can pedal
with ease like pedaling a bicycle on a level
stretch 60rpm crank speed 1020 rpm motor.....60
watts. This is where reality sinks in ....to
charge a 12volt battery at this ratio is difficult
because it kicks in at a lower speed....I'd guess
520 rpm and about 30 watts to a 12 volt battery.
Never tried it on a windmill yet.
A rope wrapped around the shaft the generator
hooked up to a battery thru a rectifier...a
a tachometer a couple of milk jugs on the end
of the rope, a fairly simple exercise in math
will give you all the data you need to know,
then you can give us your data....and we can
compare notes....