Solar Setup on BranVan
Branvan was designed to be a stealthy camper. And one of the main giveaways of a campervan conversion is a giant solar array up top. So, much like what I did for my Sprinter, I used Renogy 160W flexible panels attached directly to the roof. Flexible panels are much lighter than rigid ones, and only a few mm thick. This makes them perfect for stealthy setups. To attach them I used 3M VHB tape. This is a two-sided tape that's used for industrial applaications sush as attaching windows and panels to the sides of skyscrapers. If it can hold heavy windows to the sides of buildings, it should be fine for attaching a 2kg panel to a van roof. (Update Oct 26, 2020, I’ve had these panels on for eight months and 8000km now, and they are still as attached as ever)
A month after the install I decided that I wanted to run the wires through the back of the van instead of the front. So I peeled the panels off and flipped them the other way. I was pretty happy with how well they were attached and with some care, the removal went well. Note, VHB tape is kind of a pain to remove, you will need Goo-Gone or something like it to dissolve the adhesive. But its MUCH better than glue or screws.
When Installing them I cleaned off the "ribs" really well with isopropyl alcohol and uses extra tape up front and on the sides. It also helps if you weight them down at the critical points overnight, so I just put some weights around the perimeter and up-front
The setup works well and I've seen up to 270W (of 320W theoretical max) being generated by the system. I doubt I'll ever see full capacity for a few reasons. One is that being attached the roof, they run a bit hotter since there's not much for airflow under them. Solar panels are less efficient in the heat so this was no surprise. Flexible panels also are slightly less efficient than rigid ones, partly due to they plastic flexible coating rather than glass on rigid panels which lets more light through.
I thought about doing some sort of tilting mechanism to maximize solar gain but instead decided to "oversize" my system. I needed about 200-250W for my single 100AH battery so I went with 320W of Solar. Note, Renogy now sells a 175W version of this panel in the same size, so this setup could be 350W now in the same footprint. The passive approach works great for me as it keeps things stealthy, minimalist and requires no action on my part. I wanted a system that would work well if I wasn't around the van and this passive setup is "good enough" If I was spending more time in the van or living full-time I might want to maximize things a bit more. But for now this system tops up my battery from 40-50% in about 3 hours of sunlight.
Pros:
- Flexible panels are thin and can be attached in many ways such as to curves surfaces
- They are light and thing
- At 2mm thin they are super low-profile and much aerodynamic
- Attachment/install is often much easier and can be done without drilling or mounts
Cons:
- Flexible panels are more expensive than rigid
- Flexible panels are less efficient than the equivalent rigid panel
- They don't typically last as long (I think the plastic fades or breaks down quicker than the aluminum/glass of a rigid setup)
Good luck and if you have any questions or comments, drop them below!