From the other thread so people don't have to flip through 8 pages, the consensus is that putting your alternator on a switch and using a battery(or two) coupled with solar panels on the dash(and rear deck below the window if you have it) allows the alternator to be used only after long periods of driving or night driving.
So the question here is how cost effective is that?
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provides 90 watts peak, its max power is 17 volts and 5 amps so it will run just above where you would want to charge your batteries. Also its feeding parisitic functions at the same time you don't have to worry about overcharging for 300 bucks to get you a regulator to make sure you don't cook the battery.
10% FE increase? thats 3-4 mpg for me so 36-48 miles extra per tank or 2 dollars per tank(with gas hovering around 2/gal). so it would take 150 tanks to pay for the setup(but I'm not paying the extras in weight because the panel only weighs15-17 pounds(I'll delete something to compensate.)
Also it could be quickly interchangeable between vehicles if the plugs for the panel were in the cabin. . .
thoughts?