Stealth Roof Vent and Solar Panels

[keightley]

This is what I am thinking for my Chevy Express Van building.  I want to cover the entire top of my van with solar panesl.  I am thinking I can install them an on contractor roof rack.  About a year ago I ran across a youtube video (or was it a website... my memory is a bit fuzzy) that detailed a van build in which the builders installed a roof fan, a roof rack, and solar panel on the roof rack over the vent. Of course there was enough clearance for the roof vent.  I don't think they had much of a cover as the solar panels acted as a cover.  Is there any reason why I should not do this? 

I just did a google image search and found the pictures I have attached.  It give you an idea of what I am thinking.  And this guy, Dave Thevanman, thinks it work well.  BTW... photo credit goes to him.  You can find his blog googling "Vandwelling by Dave".  This is a custom rack, one in which I probably will not be able to afford.  I will probably opt for a commercially produced roof rack.    

I would love to know what all you veteran van dwellers think.

Keightley

 

[John61CT]

I would go lower make the maxxair less noticeable and less wind resistance.

Buy a mix of panels so there is as small as possible opening for the vent lid to stick up higher than the panels.

Maximizing watts per square foot means more expensive, doing the jigsaw puzzle a shopping challenge, but for me worth it.

Multiple solar controllers, panels matched per, or even 1:1.

 

[keightley]

I do believe that Dave Thevanman uses a fantastic vent on his van.

Keightley

 

[jonyjoe303]

I have 4 roof vents on my astrovan roof, 2x9 inch and 2 x14 inch. On a hot day they do absolutely nothing to keep me cool, even though they are still installed, on the inside I just covered them up with foam insulation. In the picture you can see 3 of them and then there is one that has a vortex fan right under my 240 watt panel, that one has no cover I had to remove so the panel can fit over it. Even when it rains, the panel does a good job of keeping the water out of my van, so installing without cover will be no problem. Installing roof vents was major work and I got practically no benefit from them. At first I installed one and it wasn't keeping me cool, so I thought maybe one isn't enough, but 4 of them is also not too much benefit. Also roof vents don't help too much in the stealth department. In the winter they might be useful to vent your van if you got a heater. I think they might only work if you park in the shade, where its cooler but also will not get too much sun for your panel. If I hadn't had those roof vents, I could have used shorter "L" brackets to mount the panel, the panel would be almost flush to the roof and mostly unnoticeable.


For ventilation I use these side vents, I have a swampcooler that is ducted to the vents, the swampcooler works alot better then any roof vents. Its not AC but better then a fantastic fan. I just gone through 6 weeks of hot humid weather and it was brutal but those side vents and my swampcooler got me through it just fine. The side vents arent that difficult to install, you don't have to climb on the roof, no worries about obstacles.

 

[Canine]

The lower the better of course, but if you took that literally, your van would be as short as a Camaro. As long as you keep it under 10 feet, you will avoid most obstacles. Less is better of course. I wouldn't sacrifice height to make the roof fan less efficient, but no higher.

Another idea to keep the frontal area as small and aerodynamic as possible could be to place the first two panels closer to the roof (not on the roof, though, to keep the hot panels from heating up the van) then raise the one over the vent to give it room. Then have a slope between the last panel and the next one in front of it to help with the wind.

I really like how that van turned out with the rack, the solar, and the vent. Back in the day some cars had two roofs to help keep the heat out of the car, so the concept works. You don't need 6 inches, but at least an inch I would say. It doesn't take a lot of room to keep the heat from going through the ceiling.

MaxxFan has a newer style of lid that may help with stealth. http://www.maxxair.com/products/maxxfan/maxxfan_deluxe.php

The weight on the top at that height is not a big deal. I've had much more weight up much higher and it won't make your rig tip over. One time I had four columns of pallets stacked on the back of a 3/4 ton, flatbed pickup. How high you ask? About 20 pallets high which was about 10 feet of pallets plus at least 3 feet off the ground for the flatbed. Overall height was over to 13 feet. No joke. The 27 foot ratchet straps used to fasten the load were almost too short. I had to make steps out of the pallets then had a friend hand them to me. When I turned, the suspension on one side completely compressed while the other side was maybe completely unsprung. It was ridiculous, but even when I purposely swerved hard to see what would happen, it never tipped over. Squirrelly? Yes, but not as bad as I would have thought. That being said, the less weight the better. Don't do something like I did- that was stupid. I told that story because I find it amusing now. Go with aluminum if you can. Steel is fine as long as it isn't overbuilt. Welders have a tendency to overbuild things. And young hicks tend to overstack stuff in the back of their old pickups.

 

[Panda]

MaxxFan has a newer style of lid that may help with stealth. http://www.maxxair.com/products/maxxfan/maxxfan_deluxe.php

I've always wondered why the black lid is considered more stealthy, is it because when extended the white lid sticks out at night?

Also are maxxair fans operational when the lid is completely dropped? Or does it cut off all ventilation?

 

[Canine]

I went with black because everything else I mounted on the on the back is black or chrome. Trying to stay away from a technicolor look.

When it is shut, there is no circulation. The fan will still run if you want, but it won't draw out any air.