Date: Fri, 18 Mar 2005 13:06:18 -0500
Reply-To: Edward Duntz <eduntz@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Edward Duntz <eduntz@HOTMAIL.COM>
Subject: Re: Solar power
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You have to compare the load that you want to power, i.e. radio, lights,
t.v., fridge, etc. to the capabilities of the battery and solar panels. Add
up the power requirements for each load in amps (divide by 12 if it only
lists watts) and multiply by the hours you want to be able to run them, then
add these together. You now have the amp-hours that you need for your trip.
Compare that to the amp-hour rating of the battery. If your load is much
more than your battery can provide, you'll want a solar panel that can
provide the power much of the load when it is sunny. So you have to check
out the output of the solar panel. Most of the panels for $30 or even $70
don't provide enough amperage to recharge a battery in a relatively short
time. Also consider that you shouldn't totally discharge even deep cycle
batteries, so you should get a solar panel that will be able to charge the
battery back up to its capacity so you can use it the next day.
I don't see any outputs listed on the cheaper panels, but the one on sale
for $99.99, reg. $149.99. is listed at 15 watts. That's just over one amp.
There's not much that you can run on one amp, so you'd have to rely mostly
on the battery, and hope the solar panel could just help to charge it while
you weren't using any load, for example if you used your radio and lights at
night and let the solar panel charge the battery during the day.
I, too, have considered adding solar panels to my Vanagon, but I think to
get panels that would allow me to be self-sufficient without running the van
to charge the batteries for a whole weekend, I'd need about $400 or more of
solar panels and a charge controller (to prevent overcharging). What I do
now is use two of the largest amp-hour deep cycle batteries that most stores
sell, and either charge them on the way back from a long trip, or just
charge them using a battery charger at home.
Ed
Subject: Solar power
> I need some advice. I am getting an Optima battery installed to run my
stuff when I am camped, and want to get a solar charger to keep the power up
when I am parked. I am looking at 2 different ones in the Northern Tool and
Equipment Catalog. One is small enuf to sit on the dash, maintains 12 volt
car, truck, MC, boat, or RV batteries for $29.99. The other does all that
plus says it is ideal for deep cycle, otherwise similiar to the cheaper one,
for $69.99. Also quite a bit bigger. I don't want to spend more money than I
have to, but want to get one that will work for me. Will the smaller one
work, or should I get the bigger one??
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