38 volt ametec power

[JW1111]

I was just about to ask this question when I read the other one on the the 30 volt Ametec, and did not want to hi jack it so I will ask the same question for a 38 volt. How much power (amps) can I expect in 14 mph winds when charging 12 and 24 volt batteries?  Thank you.

[kurt]

i have heard that the 38v amatek is not as good a performer as its 30v brother i hear about 50-60 watts max at 12v with a 4' prop.  

[fungus]

I have seen about 2.5A in a 14mph wind from my ametek 38v with 4' wooden blades.

[fungus]

A bit more info ..

I've got an anemometer and did a rough hand-drawn graph .. this was mainly to find windspeed distribution where I am but I quickly drew on some amperage values ..



I have seen a maximum of 7A from this motor in about 30-40mph winds ..

[Basil]

I have SEEN 45 watts out of my 38-volt mill. I'm sure it's did more. It has 3ft dia industrial fan blades. Best wind I have had is maybe been 15 mpr while watching it. I love it. It is great to bring a battery back up slowly.

[JW1111]

just so I am clear, is that a 4' blade (radius) or a 4' (diameter) blade path?  I was going to make my blades 24" long but maybe I will go twice that.  thanks.

[fungus]

Thats 4' diameter, each blade is 24"

[TomW]

JW1111;

Generally we refer to props by their diameter. So a 2 foot blade will produce a 4 foot prop, plus a bit for the hub area. I can see where it is confusing but most references to power versus prop are by diameter. Swept Area is the area inside the circle made by the prop tips going around and it is the Holy Grail of turbine power output. There is no substitute for swept area.

Hope that helps more than a sharp stick in the eye.

Tom