Solar panels finally mounted on RV (residential style)

[Firstascent]

I finally got my solar panels mounted on the roof of my fifth wheel, nothing wired yet but this was a big step forward in my process. I had been trying to mount these for two months but couldn’t get a good break in the weather.

I spent a lot of time deciding on install methods and wanted something unique that would easily work with the curvature of the roof.

I ended up using various components from IronRidge which is UL listed and rated to a minimum of 160mph winds, more than I’ll ever need.

The panels are 4, 370W LG panels which will be wired in a 2S2P config. I have all my other components already so note it’s just a matter of finishing the install which will have a lot of custom aspects to it.

This is my first install and I’ve learned a ton from this forum!!

 

[ElectroSolar]

Great project, i like it. Which solar controller you will use for this panels?

 

[OffGridInTheCity]

Room for more - maybe fit some smaller ones over the open spaces?
Don't mean this comment as negative, great work! just that more is better in my experience

 

[ElectroSolar]

Looks like room for at least 1 more? More is better in my experience

Of course, for cloudy days

 

[Firstascent]

@ElectroSolar I have the SmartSolar MPPT 150/100 TR VE.Can for my build.

@OffGridInTheCity haha yes room for more. I’m also trying to keep overall weight down, it all adds up quick haha. I’ll start with this but good to know I can somewhat easily add more if it comes down to it, but the plan is to stick with this.

 

[0rion]

Nice install! Could you share more about the IronRidge configuration? Are they mounted to the RV roof with adhesive or bolted down?

 

[chrisski]

Any idea how to configure the 2S2P? Looks like the right side facing south would get the best output.

I have something similar on the roof with 1300 watts of panels, and in the shortest days of the year with the low angle of sun, output peaked at 600 watts. I have two air conditioners that can shade the panels. In the summer, he output will be much higher, but I since I just installed, I don’t have the data yet.

Any thoughts on a 4P configuration? Might be better for shading like I’m experiencing. 4P might not be doable if this is a 24 volt battery.

 

[Firstascent]

Nice install! Could you share more about the IronRidge configuration? Are they mounted to the RV roof with adhesive or bolted down?

Of course, I'll eventually do a full write up when it's all complete but I did both screwed down and adhesive, although the adhesive was more of a added bonus and but not necessarily a requirement. Better safe than sorry haha.

I used SS 5/16" wood screws, 1 1/4" in length. MOST people, from my research, use a #10 or #12 screw. The main reason I used a 5/16" screw was due to the fact that is what comes with the L feet kits and fits the hole well. The included screws are a few inches long which is way too long for my application (meant for residential roofs) so I just purchased shorter lengths.

for the adhesive I used AFCAT 945. This is basically a stronger more permanent version to the popular Dicor most use for RV roof sealants. I use Dicor on most roof applications but for this I figured I'd take something a tad stronger for the extra safety factor.

On a residential install, the flat black plates are used to fit under shingles to help shed water, they aren't meant as a structural interface. I simply used it as extra support by applying the AFCAT adhesive on the bottom of the plate. The L feet is where it is bolted down though. The L feet will sit flat on the roof at whatever curvature it is at, then the cross bar mounts to those and creates the flat surface for the panels. It's a pretty slick setup and fairly priced as well. I ordered 4, 11' sticks of the crossbars (XR 100 rails) then cut to length to fit my panels. They have a flush mounting solution too or a clean look...not that anyone will ever be looking at it but me haha.

Any idea how to configure the 2S2P? Looks like the right side facing south would get the best output.

I have something similar on the roof with 1300 watts of panels, and in the shortest days of the year with the low angle of sun, output peaked at 600 watts. I have two air conditioners that can shade the panels. In the summer, he output will be much higher, but I since I just installed, I don’t have the data yet.

Any thoughts on a 4P configuration? Might be better for shading like I’m experiencing. 4P might not be doable if this is a 24 volt battery.

I went back and forth on Series vs Parallel, and honestly the main reason I went with this wiring layout was simply because it was somewhat the best of both worlds AND it worked with with my single controller, and I didn't want two MPPT's
Right now I have no tilt functionality, but it is something I want to implement in the future. I really wanted the tilt function now but haven't settled on how I want to do it yet, I kinda want to build my own auto tilt function with a remote.

Here is a snippet from my wiring diagram that shows how my panels will be wired. Also, not added/shown in my diagram yet but I have two solar 20a fuses that will be on each of the red/positive leads before it gets to the 2->1 branch connector.

I'm running a 12v system, someday I'd like to convert to a 24v setup but I'm using the new Victron Multiplus II which isn't available as a 24v option, so 12v it is. But does make it easier since most of the RV is 12v.

 

[chrisski]

Right now I have no tilt functionality, but it is something I want to implement in the future. I really wanted the tilt function now but haven't settled on how I want to do it yet, I kinda want to build my own auto tilt function with a remote.

Auto tilt would be awesome.

I have tilt on some panels, but since its manual, I have only activated it once. It takes at least 30 minutes to put six panels up and down. I’ve had winds pop up at night, as high as 35 knots rocking the trailer, and I don’t know how the panels would hold tilted in those winds. 30 minutes is just too much time to set up and take down when I’m only staying between 1 - 3 days.

The one time I used it was the shortest days of the year, so and it did boost prodcuction of those panels by about 40%. With the 600 watt panels, perhaps 300 watts flat and about 450 tilted. I was out last weekend and wanted to test it, but came down to me not wanting to be on the roof for 30 minutes twice in one day since I was leaving that evening.

If you do the auto tilt and it works, looking forward to seeing a thread, especially if its not $300 per panel.

 

[Firstascent]

Auto tilt would be awesome.

I have tilt on some panels, but since its manual, I have only activated it once. It takes at least 30 minutes to put six panels up and down. I’ve had winds pop up at night, as high as 35 knots rocking the trailer, and I don’t know how the panels would hold tilted in those winds. 30 minutes is just too much time to set up and take down when I’m only staying between 1 - 3 days.

The one time I used it was the shortest days of the year, so and it did boost prodcuction of those panels by about 40%. With the 600 watt panels, perhaps 300 watts flat and about 450 tilted. I was out last weekend and wanted to test it, but came down to me not wanting to be on the roof for 30 minutes twice in one day since I was leaving that evening.

If you do the auto tilt and it works, looking forward to seeing a thread, especially if its not $300 per panel.

Oh yeah that makes sense, if it took 30 min I’d rarely want to do it as well.

And yes that’s the goal, create something much less expensive than the limited availability of options that exist today, but also robust/industrial quality.

I have a few ideas but first I needed to figure out exactly how I’d be mounting my panels, not that they’re mounted I can finish the planning and design and start ordering materials to test!

And will most definitely post up when I have it figured out!