MagillaGorilla wrote:
Solar Panel
The RV that I tried to buy (was sold out from under me in a shady deal) had a Chicago Electric solar panel on the roof that charged the house batteries. I liked the thought of that and would like to add one to my new RV but I have a few questions about it.
1: Do they actually work?
2: If sitting in the sun, how many hours would it take to replace 25% of my house battery charge?
3: How do you mount it on the roof without creating leaks?
4: Where is the best place to run the wires?
5: Are the worth it?
Magilla,
1. Do they work:
Yes, they do. Much of WHOLE answer depends on size of battery bank, amount discharged during the evening hours, and, the amount of wattage that the solar display puts out. Obviously, the larger the display, (i.e. larger panels etc.)the more wattage is put back into the batteries during the day, based on weather, angle of the panels. (sitting flat is not as good as being directly aimed at the sun)
2. How many hours would it take to replace 25% of my house battery charge?
Well, that's been answered. But again, a small, say, less than a 100 watt panel, will have to work pretty hard, even in flawless, perfect weather, aimed directly at the sun to begin to re-install used evening voltage. Larger, say, 200 watt panels would work twice as fast and, put out considerably more amps for a given time frame of direct sun exposure. You have to consider area to mount, if you have enough room.
3. How do you mount them?
Well, that's variable too. Some folks don't mount them at all. I didn't on my first use of Solar. I had a 135 watt panel that had feet and a kick stand on it. It sat on the ground, leaning towards the sun, constantly. I put out and average amperage of 7 amps, continuously. That fed my two, 6V Golf Cart batteries very aptly. But, some will mount them on the roof, flat mounted, permanently. Some, will mount them with pivotable axis so that they can be tilted towards the sun.
And, on some of those, they incorporate and electric motor to tilt them so they don't have to access the roof for manual tilting. That depends on how elaborate one wants to get.
4. Where's the best place to run the wires?
Well, that depends on where the coach batteries are and, the closest access point from the roof to them. The general rule is, use the largest wires possible and, the shortest distance. That promotes the least amount of voltage, wattage, amperage loss. Trying to create your own "passage way" from the roof to the batteries 'cause it's the shortest, is for the most part, almost impossible. So, many might use the vent for the fridge for the down run and then, migrate over to the batteries, again, depending on length of run and where they are.
5. Are they worth it?
Well, that all depends on:
A. How much you dry camp
B. How much you want to spend on a system that will be of the best value to your system;.
C. Will you recoup the cost vs the amount of time using the system?
If one dry camps quite a bit, and, is in the regions where the sun is out for most of the time and, does not normally park in large, shade tree areas, and a couple of other variables, then a decent solar system, will adequately replenish most of a coaches AVERAGE battery bank, during the day light hours. I say AVERAGE because, some coaches have small, i.e. 1-2 coach batteries and, some, 3-4, and some, as much as 8 batteries.
The larger the battery bank, the larger the solar system needed to re-charge it in a given amount of time.
Now, most of what I'm referring to here is, using a 12V system for normal use during the evening, some TV, heater, water pump, interior lights etc. Then, asking the solar system to put back, what we've used that previous evening.
But, if you want to run toasters, hair dryers, and a whole host of other 120VAC equipment with strictly solar power, as in using an inverter, you'll need a pretty large array of solar panels on your roof. Again, it all depends on your intended use of the house batteries and, how quickly you want them replenished during good, daylight hours.
Scott
