RV Solar Panels
A lot of people ask me about RV solar panels. I hear questions like,
“What kind of solar panels do you install on an RV?”
“What size panels are good for an RV?”
“What size hail can solar panels withstand”
I live in Texas. Hail happens all the time. The panels I use from Canadian Solar can withstand up to 1” hail. Then again, if you have broken solar panels on your RV you may have other damage as well. It’s best to look at getting an insurance claim at that point.
Anyway, why do I use these two particular panels you may ask? Great question.
I have two reasons: 1) Dimensions and 2) Shading. Here’s what I’ve found.
1) Dimensions: The typical Class A motorhome and 5th Wheel is roughly 8 feet wide, or 96 inches. The air conditioner sits in the middle of the RV. When you mount your solar panels, you can get a panel on each side of the air conditioner without overhanging of the roof too much (maybe 1” - 3”). I make it a point not to increase the footprint of the roof if I don’t have to. In my personal opinion, it ruins the ascetics of the RV if you are overhanging off the roof too much. Not to mention the legality issues when it comes to how wide are able to have on the road. I just stay way far away from any of that and do not increase the footprint of the roof.
2) Shading: I’ve found the half cut cells handle shading a lot better than other panels. Typical solar panels do not like shading. These panels are designed like a grid. More like a zig-zag than a grid (from the left side of the panel to the right side back to the left). They pass power through their grid back and forth across the panel to get to the solar junction box on the back of the solar panel. Once the power gets to the junction box they connect to the wires and MC4 connectors. On a typical solar panel if you shade a part of the panel it will block the energy flow from the panel. Any kind of shading will drop the watts to next to nothing. I ran a small test where I had panel bringing in 200w of solar. Then I put my hand over the panel to block only one of the cells (4”x4”). And what I found was crazy. It dropped the panel from 200w down to 70w. So if a leaf even falls on your solar panel it could block a majority of your power. Yikes!
But I have good news! Half cut cells are engineered their solar panels to work better with shading. Instead the energy being blocked with shading and stopping the flow, it will go around the shaded parts and to the junction box.
So when I install solar panels on an RV I know there will be shading somewhere. I always try to get as much solar as I can on an RV roof. Honestly, one of the least expensive components of a solar system is the solar panels themselves. It is the other equipment of the system that are most of the cost. This includes the MPPT Controller, Inverter, Lithium Batteries, Shunt, etc. You are better off getting as much solar on your roof and spend a little bit more on inexpensive panels. Over the past few years the cost of solar panels have gone down drastically. It used to be $5/watt. Now it is down to 52 cents/watt.
One last note: The arrangement of your panels is important too. What I do is if I have room for 8 solar panels on the RV roof, I connect 8 of these solar panels in 4S2P. This means 4 of my panels on the Left are in Series (plus to minus) and the 4 on the Right side of the RV are in Series. Then I put them in Parallel using Two 2-1 MC4 Connectors. This keeps the voltage high and amps low.
If you have any questions I’d be glad to help! Send me a message. I am also open to any feedback.
I hope this helps!