1700W Solar Panel Installation on Class C Motorhome

[HookEm]

As introduced in this thread: https://diysolarforum.com/threads/question-about-solar-panel-install-on-whole-roof-of-an-rv.33507/
Here are some pictures describing the 1700W Solar DIY installation that I've just completed on our Winnebago Navion.

The structure holding the panels is built from Aluminum Strut rails (from Grainger) and Aluminum Strut Angle brackets (from McMaster Carr). The Strut rails are held to the rooftop with VHV tape (3M RP62) and then covered with Lap Sealant (Sikaflex 715). The height of the structure is 8.25-in, with the front panel tilted upwards to 11-in. I tried keeping the structure as low as possible while providing reasonable clearance for the Mabru 12V A/C unit that's installed up-front. Also, as shown, I did have to account for the Roof-Access Ladder on the rear passenger's side, and the Skylight on the rear driver's side,

The 4 LG Solar panels (425W each) are bolted to the Strut rails that run from side to side (not shown in the first few pictures), and on the top, they are also held in place by End-Clamps which are bolted to the Strut rails that run from front to back.
--EDIT--
The bottom Strut rails are angled at 3-Degrees to account for the curvature of the roof... This was done by cutting the bottom of the Vertical vertical support pieces at 3-Degrees on a Miter Saw.

 

[HookEm]

Here are a few more pictures:

 

[ponobill]

Nice installation. I did something a bit more shop built on a 1978 GMC Moho. I wasn't too worried about roof penetrations since I did all the drilling below the roof rails, but then had to brace them on top of the roof--so much for my conservative approach. I raised everything above all the roof junk as you did, but if I did it again I'd clear all the vents and AC away and have a much lower installation. I'm replacing the noisy inefficient RV roof AC with a mini-split which draws a third of the power for better cooling and has no bump in starting current--most roof mounts have 5X starting current unless they use a soft start, and then it's still 2 to 3X.

My system has two modules from a Tesla Model S for an 11.6 KWh battery and a 24 VDC, 120 VAC 6KW pure sine inverter. The entire system was an experiment, I'd do almost everything differently if I were doing it today. Like 48V bus instead of 24, and 240 V split vs. 120VAC, but live and learn. Since I took this picture I added a deflector to the front of the PV rack.

I did a few articles on this project on my personal blog. Woefully out of date, but there might be information people would find useful. I started off with a lot of stupid ideas and improved them all the way up to not so bright but at least it works. I still have plenty to learn and places like this forum are where I got the best ideas. https://www.ponostyle.com/fritz-getz-solared/

 

[jberger]

Ponobill, that is a GREAT looking GMC.
I have always loved those units, and yours is the best looking update I've ever seen.
Great work!

 

[HookEm]

Wow, that's a really nice job!
(My rooftop is just fiberglass with a 4" foam-fill, and a few support beams who-knows-where... but the VHB tape should hold fine... I hope!)

 

[ponobill]

Wow, that's a really nice job!
(My rooftop is just fiberglass with a 4" foam-fill, and a few support beams who-knows-where... but the VHB tape should hold fine... I hope!)

The VHB is probably fine. I use little 1" X 2" VHB-attached bases to add footstraps to my wing foil boards. They don't come off even with serious loads and mistreatment. In fact, you'd better be right about where you want them to be since they're a bitch to remove