Automobile wind generator

[Hakuna matata pools]

I own a pool business that uses a 12v battery powered pool vaccume that attaches and detaches from the rear of my truck. It has to be charged very 2 or 3 days in order to work properly. I would like to add a mini wind generator to it with a charge controller to keep the battery charged longer that 2 or 3 days. I drive about 100 miles per day, with average speed of 45 miles per hour but up to speeds of 65mph at times. I understand that the additional drag will cost me gas money and it's not possible to charge the truck battery, but that is not what I'm after. I want to charge a separate battery that is not hooked up to my truck. I have tried several mini permanent magnet motors, getting 6-8 volts, but not to sure on amps. Any help determining which motor to use would be much appreciated. As of now I'm looking at a rc plane motor and prop. Really just need to know what size motor (amp output/rpm needed) to use to get the effect I'm looking for. I would think I need at least 4 amp output to actually charge the battery for as much as it's used.

[Ralph Day]

What about just upsizing the alternator on your truck and charging from that? Probably a much more efficient way to charge the battery.

Ralph

[Hakuna matata pools]

The problem with that is the vacuum has to be disconnected from the truck up to 16 times per day. Out of those 16 times it's possible I might forget to unhook said wires and break them shorting my whole truck out. Or I might forget to hook them up and short out the whole truck. Trying to either use solar or wind to charge it where the charging unit is installed on the vacuum itself so I don't have those issues. Plus it's fun making things like this.

[Hakuna matata pools]

I think I'm going to go with a tractor generator and add a fan blade too it. Use a charge controller and mount it to the vacuum.

[Sean Moore]

Split charge unit, no need to change the alternator - with a flying lead to the pump.

You are wasting your time with your other ideas.

http://www.antares.co.uk/original-split-charge.html

[Ralph Day]

I think Sean hit the nail on the head. Now, can you find one in North America?