Charge Batteries by Idling Tow Vehicle?
This may be a dumb question, but since every tow vehicle has a generator which is connected to the batteries and they charge while driving, how about hooking up and charging at the campsite while idli...
Forum Discussion
John & Angela wrote:
I wouldn't recommend it for a trailer battery charging through the 7 wire harness but for the class C motorhome bunch you can kind a make it work. But you need to put in some decent size wiring. We made a direct run of 2 or 4 gauge (can't remember) from the alternator on the V10 to the 2 AGM batteries in the coach. We also put a meter in line. When they are run down we will see charge rates north of 40 amps at idle, sometimes quite a bit north. A v10 is quieter than any generator I have ever heard, ANYWHERE. Fuel usage is around 1/2 gal an hour. Wear and tear, couldn't give a care. I bought it to use it. It already has over 150,000 K on it and a couple hundred hours idling probably won't hurt it. Beats hauling around a generator and fuel, neither which I have room for.
Having said that we have around 400 watts of solar on the roof, which works great until you have endless days of rain.
Too each his own.
Well stated ... and right on target!
For staying put in one drycamping spot with enough average sun day after day, solar is the way to go. But for hit and run type of drycamping with some driving miles every day, or every few days - we've just stayed with the alternator/generator approach so that we're ready for any kind of sky to keep the battery bank charged when drycamped in between driving spurts. I've considered portable solar, but decided that doesn't make as much sense as rooftop solar if we should ever add solar to our mix. Our rig came with an excellent Onan built-in and the little very quiet 30 year old Honda was given to us years ago and it's still in pristine shape - so why not bring it along and use it after boost charging with the V10's alternator.
From the curves on page 6 of this .pdf, our Ford 130 amp alternator is good for up to around 80 amps (temperature dependent) when the V10 is idling. Note that the alternator is spun 2.72 times faster than the engine's crankshaft RPM:
https://www.fleet.ford.com/truckbbas/non-html/2005/vs_pdf/05elect.pdf
