Christine has been back in Ft. Lauderdale for the past ten days enjoying some much needed Gramma time with our TEN year old Grandson Liam, seen here with his Dad Tim working on a new puzzle. 
As well as visiting dear friends of many years like Kathleen. Lucky me, while I can’t be there this time I often get to spend time with BOTH of these Gorgeous Galls. 
The pups and I have been holding down the fort here on Road Runner Ranch in Southern Nevada where the temps have started to drop and so Razz has taken to sunning himself on the solar panels for some extra warmth and seems like a good segue into today’s Lance progress update post on ……………………….. you guessed it; Solar Panels.
Living the nomadic and remote life that we always have, we are big fans having solar power be the primary source for all our daily electrical needs, which are quite extensive. On our boat Mobius we had factored solar panels into the design from the beginning and were able to have 16 large panels on three different roof surfaces on that boat such as these eight panels on the upper Pilot House roof. 
And here on Road Runner Ranch we have 18 solar panels in two banks, this one just set against one of our 40 foot shipping containers and the others you can see Razz laying on above. These keep our big EG4 Wall Mount 15kW battery charged up every day and running this through our EG4 6000XP Inverter/Charger provides all our electrical power for day to day life here. 
This is where the time I spent meticulously building Lance in a 3D model using Fusion 360 pays off. I could create a model for each of the different solar panels that I was considering and see how they would fit onto Lance’s roof and on the framing.
With much less surface area available for mounting solar panels on Lance’s rooftop I wanted to fit the maximum amount of solar output as possible and played around with lots of different solar panel models to get the Goldilocks combination that would fit. 
Over the years I have found it works best to design the overall electrical installation as a complete system because there are a lot of different pieces to this puzzle and they are all very interconnected not just electrically but also features and dependencies. I created 3D models for all of these components as well and you can see most of the components here in the Electrical Cabinet on the front Driver Side corner of Lance’s Hab/Box. There is a LOT to unpack here so I’ll cover the electrical system in a future post and get into all the details then for those interested.
After much deliberation and testing in the model, I decided to go with four SilFab 420 Watt QD panels which I purchased from Current Connected almost a year ago now. I was able to get these all installed this past May in time to help power us on our marathon maiden voyage with Lance driving out to Portland Maine and back this summer. For those interested you can see all the specs of these panels here and of course with the march of time since there would now be even higher output panels but we’ve still ended up with 1680 Watts of solar power and it has been more then enough to keep us fully powered all the time.
We do have additional sources of electrical power such as this 320 Amp 12V 3.8kW alternator on Lances Paccar/Cummins engine that can provide up to 4k of power anytime that engine is running. However on our summer test run I had not completed the installation of the Arco Zeus smart regulator so the alternator wasn’t working that whole trip and the solar kept our batteries filled the entire time so that was a pretty good testament as to how well the solar was working. 
I decided to use 10 foot lengths of galvanized Super Strut to mount the solar panels on Lance’s roof. I would have preferred to use aluminium Super Strut but the delivery times would not have been in time for me to get the solar panels mounted before our trip so I went with galvanized steel and they have worked out vey well. I laid them out as you see here, two lengths on each side and two down the middle. 
I added additional 4 foot lengths of Super Strut so that I would have a mounting system for the whole 14 foot length of Lance’s roof for mounting any additional items in the future. 
I kept the mounting very simple as well by cutting pieces off a length of 2” aluminium L bar, 
drilling two holes in each one for the mounting bolts, 
and using the very handy Super Strut M8 threaded inserts to bolt them solidly to the lengths of Super Strut. 
Quick, strong, simple; what’s not to like?!! 
I then made up the cables using extra UV rated cables, Red for the positive and Black for negative and crimping the MC4 twist lock connectors that are the most commonly used for solar panel wiring and which I’ve used a lot in previous projects so I have all the specialty tools, crimpers, etc. some of which you see here in the photo. 
To fasten the brackets to the solar panel frames themselves I inserted aluminium M6 threaded Riv-Nuts into holes I drilled into the vertical AL frame on the solar panel and then used this tool which compresses the threaded inserts and locks them to the frame. 
End result looks like this. 
One bolt vertically to fasten to the Super Strut and one horizontal to bolt into the solar panel frame.
For those wondering, I fastened the lengths of Super Strut to the roof using Loctite 8X PL Premium Fast Grab which is supposed to be 8 times stronger than traditional construction adhesives which I’ve used before. Probably overkill but you certainly don’t want solar panels flying off the roof when running down the highway at 70 miles an hour! To prevent any pooling of rainwater between the surfaces of the roof and the Super Strut I caulked all the edges with 3M marine sealant which I have LOTS of experience with on our previous boats. So everything fully sealed and eXtremely well fastened to the roof. 
Solar panel output drops off significantly with the rise in temperature of the panels, the irony of which isn’t lost on me, so I left this 4” gap where the two panels down each side meet up. This along with the 2+ inch space between the panels and the roof keeps them as well ventilated as possible and the efficiency of their output was very good even in the 40C/105F days we had several times on the trip AND while I was installing these panels! Talk about a cat on a hot tin roof! Ouch! 
To make it a bit easier to run the cables AND give me a wee bit of shade, I was able to remove the inner brackets and use the outer ones like a hinge and prop up one lengthwise pair of panels while I ran the cables. 
I ran the eight cables for all four solar panels to converge at this point on the front DS corner as this puts it directly overtop of the Electrical Cabinet below where they need to go and thus provides the shortest cable run for least voltage drop. I drilled the only hole in the roof for this but it was a BIG one as you can see and then I used more 3M 5200 to seal a short length of 2” PVC pipe as a safe conduit through the roof for these and all other cables in the future. The red square you see on the bottom is 3M VHB Very High Bond two sided tape which is a fabulous product for gluing almost anything to anything and it never comes off. 
PVC box now glued down to the roof over that PVC pipe and the cables run non stop down into the Electrical Compartment below.
Each solar panel needs to have a shut off so I used these DIN rail mini circuit breakers to do that and provide over current protection.
I use threaded glands, the black things you see here and above, to give each cable a watertight entry into all junction boxes. 
This is what it looked like inside the Electrical Compartment where the cables pass through. 
The output of solar panels is a much higher voltage than the batteries and needs to be regulated to different charging stages to properly charge the big LiFePO4 Lithium EG4 batteries in Lance so the output of the solar panels goes through a MPPT controller which looks after all of this. Although it isn’t common, the most efficient setup is to have a dedicated MPPT controller for each panel and so that’s how I’ve always built our solar systems. Those are the four Victron Blue boxes you see on the upper Right here. 
It’s a bit of electrical spaghetti and took a bit of time to route and connect all these cables but keeps all the wiring very well contained in the wire ducts like the one running vertically up the far Right side and will have a cap that snaps onto those fingers you see here. 
Final cabling is to take the output from each MPPT controller and connect them to the main 12VDC electrical bus bars which are the silver coloured bars you see running up on the far Right here. If you look closely you can see two Red and two Black cables connected together at the top and then the other four below so now all the power from the solar panels is connected into the 12VDC electrical circuit.
And here’s what Lance’s 1680 Watts of solar roof looks like.
The extra length of Super Strut has already come in handy for my temporary for now mounting of our Starlink dish and the 4” PVC tube running down the middle for storing long lengths of material I like to have for ongoing projects while we’re on the road. Go ahead and tell me you’re surprised?!?!
Did I mention that we LIKE solar panels???
And that wraps it up for this weeks progress update, hope it was informative and enjoyable and let me know what you think in the “Join the Discussion” box below.
As this recent holiday has reminded me I am indeed one eXtremely fortunate fellow with SO much to be thankful for, not the least of which is YOU, for the time you choose to take out of your busy schedule to read and comment here and join us on this latest adventure of the Ambo Nomads.
I’ll be back again next week with the next installment and hope you’ll join me again for that.
Ciao for now,
Wayne 
and “Sunny Boy” as he tells me he now likes to be called.
Thanks for the solar install info.
How did you prep the surface before you glued down the super-strut? I have a stepvan with a fiberglass roof that’s painted white. Think I could install the same way?
Hi Bill, basically I just did a very thorough cleaning of the painted surface using Acetone first and then another clean with Iso Propyl Alcohol. I taped off the area where the SuperStrut would lie and gave that a bit of a scuff with some 3M ScotchBrite type pads and then one final clean and put the SuperStrut down with the Loctite PL 8X. If you spend a bit of time on YouTube and with an AI chatbot, you’ll find quite a few other examples of this method for attaching SuperStrut and UniStrut to the rooves of RV’s, trailers and the like, several of which have been done several years ago and have stood up very well.
Based on my experience then, yes I would recommend this method for your consideration and hope it all goes well with your van conversion.
Wayne
Outstanding Wayne. I always enjoy your project updates. Excellent craftsmanship, as always. Do you mean to tell me that you fastened those galvanized sections to the roof of Lance without any mechanical fasteners – just 3M Loctite? Really? It’s good stuff, no doubt, but personally, I wouldn’t have trusted it. Maybe I missed something?
Hi there Wade, always a treat to hear from you. And no you didn’t miss anything, there are no mechanical fasteners holding the SuperStrut onto Lance’s roof.
Like you I too had my doubts at first but I research everything and spent a good bit of time on this topic and eventually became totally confident that it would work very well. In addition to having the solar panels very well attached to Lance both at highway speeds and during any severe storms we might encounter, I also wanted to avoid having any penetrations in the roof or anywhere else on the box/Hab. Lance’s ambo box was built by Horton Emergency Vehicles which is regarded as one of the best ambulance builders out there according to the many fire departments and medical ambulance services that use them. One of qualities that has really impressed me as I got to know this build very intimately is that they build the frame by welding lengths of thick wall 2″ square aluminium tube and then they attach the 3-4mm thick AL skin using just adhesive. All of these AL panels on the roof, sides, front and back are build from single sheets of AL so no seams anywhere. Then because the AL would warp if they were to weld the skin to the frame, they use adhesive similar to what I’ve used for the SuperStrut. End result is this incredibly strong and sealed aluminium box which I’ve also discovered that to be certified, these boxes have to be tested to be able to withstand multiple 360 degree roll overs without causing any structural damage. We’re certainly hoping not to ever test out that capability but you these are some of the resons why we became convinced that an ambulance made an incredible base to build an XRV from.
No surprise to you, I did a LOT of research into this as I had the same doubts you’re expressing but I found countless examples of this type of construction both specifically for attaching solar panels to RVs as well as commercial building construction and found that this is exactly the kind of application these adhesives are made for. I did a bunch of my own “destructive testing” with pieces of SuperStrut and parts of Lance’s skin I had cut out for windows and the like and no matter how hard I tried I could not get the joint between the SuperStrut and the painted AL surface to crack, give way or move at all. Taken together I became fully confident that this method was going to work well and I’ve kept a close eye on these joints over the past 7 months and 11,000 miles we’ve put on Lance so far and it is all as good and as tight as when I first put it on.
Long winded answer, so unusual for me! but that’s my story and I’m stickin’ to it!! 😉
Please give Diane some hugs from us and when you have a moment drop us a note with an update as to what you guys are up to of late and plans for the new year. We’re heading South in few weeks in Lance, first to spend Xmas week with our two Grandaughters in the LA area and then on to Baja for the first part of next year. Then we think we may do a U turn and head North and go up to see the Yukon, NWT and Alaska for most of the rest of the year. So stay tuned as our adventures continue.
Wayne