Odd Charging Ideas

[JeremyD]

Question. Would hooking an alternator up to a squirrel cage style fan and mounting it on top of my bus provide wattage to hook to a charge controller for a battery bank and thus utilize the not "free" but endless supply of wind? I understand drag and that there is no such thing as free energy. Not my hope. But... given I don't think the added wind resistance will greatly increase my fuel consumption on the bus, could it be an additional way of providing charging capability for my electrical system. I know alternators are not battery chargers but if I have a charge controller, a box that can take in a fluctuating amount of wattage and create the ideal conditions for charging a battery, is this a cost effiecient way of charging batteries. I am likewise thinking of adding a second alternator to the engine and using the engine belt drive, again pulling load from the engine and increasing fuel consumption. Not sure if it is a waste of time. Guess the big question is can the blower motor + wind resistance against the blades produce enough torque to spin the alternator? Thoughts?

[cadillackid]

people have done studies on this and found that in fact it does create more wind drag than you get out of it.. enough so that you are better off putting an additional alternator on your engine...

solar panels on the roof however are a good way to charge. esp if you are planning to have them anyway... yes they create drag. but also giver you power when parked..

the wind while driving helps to keep the panels themselves cool which gives you the best output..
-Christopher

[JeremyD]

I read that in a few other locations but since I have extra alternators laying around, I thought maybe I could come out positive since initial cost would be, well, to the project budget zero. Thanks for the reply. Maybe I could rig up some fancy door to open them only when braking lol then the drag would be helpful but... albeit a very lame use of my time and resources lol.

[JeremyD]

I have read on a few sites saying you cannot hookup the output of an alternator to a solar charge controller as to not have to buy to separate charge controllers. Is there a thread talking about this? Or can someone help explain why I can't do this?

[john61ct]

Absolutely not worth considering even if everything were free