Solar Panels are a key element for off-the-grid vanlife; if you say freedom, we say solar power! The electrical system of our campervan is designed to power our appliances (fan, lights, 12V fridge, etc) and can be charged with solar power, alternator or shore. The present article only covers the installation of the solar panels; if you are wondering “How many watts of solar panels do I need on my van?”, then we have a very comprehensive Electrical System Design Guide for you here:
Update 2020
Yes, the panels are still holding strong since we installed them in 2016! We didn’t have to re-do anything; we occasionally check them and it’s all good 🙂
We would recommend this installation method for a new van, but we do NOT recommended this method for an older vehicle. Remember that the tape is holding on THE PAINT, so if the paint chips off (because of rust) you might loose your panels and potentially KILL someone.
TIME SPENT ON THE JOB: 6 hours
TOTAL COST : 570$ USD
MATERIAL:
- 2 x solar panels (Buy from Amazon)
- 3M VHB double-sided tape 1″ width (Buy from Amazon)
- 2 x Renogy Z mounting brackets (Buy from Amazon)
- MC-4 Multibranch Connector pair (Buy from Amazon) (This is to wire the panels in parallel if using a PWM charge controller. If using an MPPT charge controller, do not buy this as you’ll most likely wire the panels in series)
- Right angle cable gland 3/8″ (Buy from Amazon)
- 15′ Extension Cable Pair with MC-4 Connectors 8AWG (Buy from Amazon)
- Dicor 551 LSG-1 Lap Sealant (Buy from Amazon)
- Isopropyl alcohol
- Primer, Paint & Clearcoat
TOOLS:
- Drill
- Caulking gun
- File and sandpaper
HOW WE INSTALLED THE SOLAR PANELS ON OUR VAN
1- Test the setup before the installation
Right when we finished installing everything, we realized that we did not test any of the components! If any item was defective (panel, connector, wire), we would have to disassemble everything… Fortunately, things always work for the best so we did not have to undo our work!
To test, we could have just connect the panels to the MC4 parallel connector, then connect to the extension cable, and finally check the voltage at the end of the extension cables. We did that at the very end of our installation.
2- Pre-install brackets on the solar panels (4 brackets for each panel)
It’s easier to do this on the ground…
3- Relocate the brackets in the inside edge
This is to minimize the gap between the panels, so they are installed toward the middle of the roof and are less visible from the ground. A minimum gap should be left to account for thermal expansion and for installation access.
4- Install 3M VHB tape on brackets
We selected 3M VHB tape to minimize drilling through the roof. AM Solar have been doing it for a long time and reported to never have lost a panel. Where a screw will grip through the sheet metal, the tape rely solely on the paint to hold; therefore, we don’t recommend to use tape on rusted, damaged or used paint. In other words, we trust the tape method because the van is NEW. Also, we check our panels installation regularly.
Per manufacturer recommendation, the minimum application temperature for 4991 tape is 60F.
5- Cut the 30′ extension cable in half and pass it through the glands. Leave about 12 inches between connectors and gland.
It required a lot of force to pass the cable through the gland thanks to the right angle. It’s better to do this on the ground.
6- Pre-fit solar panels on the roof to define location of cable glands
This extension cable is not very flexible. We found it easier to work with if we install the glands at approximately 12 inches from the panels.
Mark the location of the solar panel to avoid having the measure again afterward.
7- Remove solar panels and drill holes for the glands
We pre-drilled and then use a hole saw.
8- Break the sharp edges with a file and smooth the surfaces with a fine sandpaper
To prepare the surface for touch-up.
9- Apply Primer, Paint & Clearcoat on drilled holes
This is an important step to prevent corrosion in the future.
TIP: You can have your exact van color prepared for you in almost any auto-parts store. Just give them your color-code (printed on the driver’s door frame), year of production and make.
10- Think and prepare cable routing on solar panels
This is to prevent cable chafing on the roof and damaging the paint. We also installed a protective tape on the roof afterward just in case.
Now that we look at the picture below, we’re not sure it will pass the test of time. You might come up with a better idea!
11- Fit solar panels on the roof and connect all the cables
See previous picture.
12- Pass wire through the roof without securing the glands yet
13- Clean roof with isopropyl alcohol, peel off 3M VHB tape and press firmly to adhere
No picture here. We had to act fast and it turned out more complicated than anticipated: you get no access to the center of the roof, the cables must be neatly fitted and you get one chance only to stick the 3M tape at the right place…
14- Fasten the glands to the roof
15- Seal all the brackets and the glands with Dicor Lap Sealant
The bracket are sealed to prevent water contamination with the tape; it should help in the long run. We could not seal the inner edge of each bracket because we had no access.
16- Final Test
We don’t have the charge controller installed yet, but we can ensure there is voltage coming from the panels.
It works!
17- Have a pint of fresh Double I.P.A
We deserved it!
18- Have a Poutine
We know what you are thinking; but we also know that you would love it if you try. This is Quebec fine cuisine.
ON SECOND THOUGHT…
2 years 4 years later and we’re still super happy with the solar panels! We did upgrade our PWM solar charge controller for a MPPT solar charge controller, but we updated our Electrical System article and Wiring Diagram accordingly. We also reviewed the Victron MPPT charger and the Victron system monitor:
INSPIRATION OF THE MOMENT
Did you ever have this wild dream of quitting your job and travel the world in a van? These guys had this dream, and went after it… very motivating reading!
Download the eBook from Amazon.
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ABOUT US
Hello! We’re Isabelle and Antoine 🙂 In 2017 we sold our house (and everything in it), quit our engineering careers and moved into our self built campervan. We’ve been on the road since then and every day is an opportunity for a new adventure; we’re chasing our dreams and hopefully it inspires others to do the same!
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CHEERS!
I’ve seen many van builds with solar power but they always mention a battery of some sort (usually lithium). Does this particulate setup not require one at all? Have you ever had an issue because of this?
Thanks!!
The whole idea of having solar panels is to store the energy from the sun in a battery so when you don’t have sun, you can still use your electrical devices (fan, light, fridge, etc). I strongly recommend reading this article: faroutride.com/electrical-system/ 🙂
Hi Antoine! Are your panels still wired in parallel with the Victron MPPT charge controller?
Yes still parallel, we didn’t change the wiring.
Do you think you could have possibly added a second Maxxfan without cast shadows compromising the solar panels output?
Hey Patrick! I just installed my solar with a second fan in the rear. With the angle of the maxxair / orientation of the lid when raised (high end faces the back of the van) there doesn’t seem to be much, if any, shadow casting onto the panels. I’ll know more tomorrow as I check it throughout the day but as of this afternoon it looked good! Hope that helps some
Also, what kind of tape did you use to secure the cabling under the solar panel?
Leslie
Hello and like the rest THANK YOU!
I’ll be installing my solar panels soon and I plan to use the pre-drilled/tapped M8 holes in the roof for the outside brackets of the solar panels to secure them down, while using your method with 3m tape & sealant for the inside brackets. But I’m thinking it must be a bad idea to use the predrilled holes if you didn’t do the same in your conversion?
Leslie
So there is no need to buy a roof rack system (i.e., either rails and/or cross bars) to attach the solar panels? You just simply put the VHB tape on the anchor of the solar panel and attach to the roof and cover with the lap sealant? With no roof rack system, is this why there seems to be a slight angle where the solar panels meet in the middle of the roof? I’m getting excited to find out there might not be a need to purchase a roof rack/rail/cross member system. Please advise
We didn’t want to install a roof rack and using VHB tape on our roof was possible because the van was new (tape is holding on the paint; it would not have been possible if there was any sign of rust!). And you’re right, the panels are slightly in angle as they follow the roof curvature.
I’m a fan of your site and info, but can I kindly ask you to remove the suggestion of mounting panels via VHB (or any structural adhesive for that matter).
This approach it too prone to error, and failure at highway speeds can cause death/injury to other motorists.
Here’s a recent story of 3 dead as the result of dislodged solar panels, though the article does not mention how the panels were fastened.
https://www.abc.net.au/news/2020-10-02/tasmania-fatal-crash-midland-highway-near-ross/12726538
Hi,
I see your point.
But it makes me wonder: where do we draw the line? Because one could say that building your own electrical system is dangerous. It is prone to error as well, because all the connections (crimp, wire gauge, fuse, etc) and all. And the same could be said about Propane, all the wood work inside (in case of accident)…
So I think I’ll leave it there, with a proper warning:
“We would recommend this installation method for a new van, but we do NOT recommended this method for an older vehicle. Remember that the tape is holding on THE PAINT, so if the paint chips off (because of rust) you might loose your panels and potentially KILL someone.”
Cheers,
antoine
Hey, I appreciate all of the info you provide so much! What are the dimensions of your panels?
Alex
Hi guys!
I’ve been working on my camper for the last couple of weeks and have been putting off the solar panel install since I can’t quite bring myself to cut my brand new cables in two. Did you guys just snip them, and then crimp them back together on the inside?
Thanks!
Noah
Don’t cut the panel’s cables. Leave them on and connect them to the extension cables. Cut the other end of the extension cables; discard the MC4 connector on the end that you just cutted as you don’t need them (the solar charger connections require bare wire). Route the extension cables through the roof and connect them to the solar charger.
Hope that makes sense.
I’m thinking about getting solar panels so that I don’t have to spend that much on power anymore. Knowing I won’t have to take time out of my day to clean them off and maintain them makes this decision so much easier.
Thanks so much for all your notes. I followed your instruction for my solar panel installation exactly.
I found a bolt loose lying on my roof near one of my solar panels. It obviously came from one of the brackets but because of the tape and the dicor, I can’t get access to find the problem. It worries me that one of the brackets will no longer hold the panel securely. Have you ever had loose bolts and how did you fix it?
Okay. Did the solar panels today, finally.
Different from you guys, but I did incorporate some of your crazy ideas!
Same panels (I didn’t know they were Canadian! You guys are shameless!) Same fittings.
Turns out, if you drill a hole in the middle of the 4 mounting holes in the fitting, for a M8 bolt, and use the FORD roof anchor holes, the panels end up about 8 mm apart in the middle. So I got a 3/4″ box aluminum rail from Lowes, set it in lapping sealant to be under the inside edges of the panels, and used two 1/16″ lines of your VHB tape to glue the panels to the box rails. (So I DID use one of your ideas! So there!)
I do plan to attach the panels together front and back with aluminum straps.
In the end, I am about 1/2″ lower than your setup (because the roof over the bolt holes is recessed), so better gas milage I guess. But poorer cooling, esp since air can’t get through the middle of the panels via convection. Should be okay, but we will see.
For the wires, I was a little worried, what with having done the ceiling of the van last summer, and not really wanting to rip it down. But now, I am going thru one of the access holes in the back and covering it with a Go Power Plate. Wires about 5 ft longer than yours, but okay I think.
So, I was happy. The Panels are bolted to the roof. And I did not drill a single new hole in the roof of the van. Now, I may be need to buy a 1K$ battery…there goes my stimulus check…
One Q: why did you cover your VHB attachments with lapping sealant? Is it because water degrades the VHB attachment? If true, I might haf to put a bead of sealant in the “V” between the panels, over the aluminum box.
Cheers in lockdown,
Don
PS Good time to rotate your tires…