Gaetan
Jonquiere, Qc. Canada
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what would be the minimum requierement of solar panel to maintain 2-6v batteries charged while in storage and everyting unpluged
Gaetan
Gaetan St-Hilaire
2004 silverado 4/4 2500HD long box Duramax/Allison
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pianotuna
Regina, SK, Canada
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Hi,
The absolute minimum would be 5 watts per 100 amp-hours, but 12.5 watts works even better and probably would cost a similar amount of money.
Regards, Don
Kustom Koach Class C 28'5" 256 watts solar, 875 amp hours in two battery banks 12 volt batteries 2500 watt inverter.
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KD4UPL
Swoope, VA
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Everything unplugged, 5 or 10 watts would probably do it. However, the smaller the solar panel you buy the more expensive it is on a watts-per-dollar basis. You may find you could buy a 30 watt panel for not much more money and have it be much more useful when camping without hookups.
If you decide you want to go larger I would start at about 50 or 75 watts. This would go a long way toward being able to keep your batteries charged in an off grid situation. Larger solar panels, typically 180 watts and up, can usually be had for under $2 per watt.
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Golden_HVAC
Fulltime, CA, USA
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Hi,
I would recommend a minimum 50 watt panel.
When camping, the Co, propane detector and refrigerator will use about 35 AH daily and a 7 amp 120 watt solar panel will make up that amount of power daily.
THe larger panel is what I would really recommend to avoid running a generator to make up the power used each day. While normal camping will use a lot more power than the 120 watt panel will make, the 35 amp hours provided daily (with a average about 5 hours "FULL" sunlight, is really only about 2 hours full sun, and 5 hours spent getting to the full sun = to about 1.5 more hours, and 1.5 hours more after noon.
While some say to size a solar panel at 6 hours X peak amperage, it is less disapointing to size it at 5 hours X peak current, you can always achive that (well not in Canada in the winter, but in the summer).
So whateer size you get, I think you will enjoy camping more with the silent charger.
One sometimes asks how I can justify spending $3,000 or so on a solar system? Well saving $10 a night and camping over 300 days between 1994 and 2004 did pay for the system! And I really enjoy dry camping, with the neighbors at least 300' away from me! Sometimes more than a mile away. You just can't buy your way into a campground that secluded.
Fred.
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rbrand
Victoria, BC, Canada
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I have a single 15 watt panel. Which is more than adequate to maintain a full charge in 3 AGM HD batteries, when the sun is shining.
Through our long grey days of winter I have to turn on the converter for a few hours every couple of weeks and this is through a Canadian winter.
The less you plan the more options you have.
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PapPappy
Wilmington, NC
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You should look at those (2) 6V batteries as a 12V system. You can find chargers that will handle that fairly cheaply. I think I found one at Walmart for about $60.
But, I'd recommend getting something a bit more substantial, so that you can charge the batteries while you are camping too. A maintenance charger for the winter isn't going to charge the system when you are using it....or I should say, it won't do a good job.
I can't speak for the quality, but you can check out Harbor Freight, and see their 45W system. It's only about $180 and includes some lights (which you probably won't use) and an inverter (which you might).
Bill & Claudia / DD Jenn / DS Chris / GS MJ
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Chuck&Gail
In the Colorado Mountains
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Just to KEEP them charged, with all disconnected? A $25 battery maintainer will work fine IMHO. I've used them for years. I agree if you spend several hundred dollars or more the panels are cheaper per watt, but only you know if that is a good use of your money.
Chuck
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Not yet camped in Hawaii, 2 Canada Provinces, & 2 Territories
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Camper_Jeff_&_Kelli
Seattle
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I have a Kyocera 80 or 100 watt panel that puts out up to 4 amps on a sunny summer day. The batteries stay properly charged over the summer according to the voltage meter on the solar controler.
During the winter, I've never seen it put out more than 1.2 amps. In winter, my batteries slowly lose ground on keeping their charge so I turn on the power converter to charge the batteries for a few hours every third day. My camper came with a pair of Wal Mart group 24 batteries I believe they are. Regular lead acid.
I plan to measure the space in the batterie compartment and replace those with the largest AGM's I can get in there. Either Lifeline or Optima. Still trying to settle on which is the better battery.
J&K
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pianotuna
Regina, SK, Canada
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Hi Camper Jeff,
Optima's are good batteries but because of their spiral design do not have as much energy density as the same "footprint" for Lifeline. I'd not consider Optima the optimum choice for a house battery for that reason.
You may wish to look at Universal batteries, too:
Universal batteries
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woodhog
NS
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Where are you "storing" your camper??
2004.5 Dodge 4x4 SRW Diesel 3750 Lb NITTO tires Bilstein Shocks
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