Solar panel max length on e350 and mounting

[lifemonkey]

Based on reading numerous posts from back in 2015, I've learned a bit more about solar/battery needs, but I have a question since things may have improved a little since then.
After reading the poop sheets diary on whether solar is right for you as well as recent posts about the best refrigerator and general info about typical amp usage of usual devices, I am gathering I will be fine with 200-250 watts of solar initially. I haven't done the complete math on all my devices, but am just roughly estimating based on what I have read and others’ experiences.  

I have an E350 standard length / normal top van. Space is limited up top.

In considering economic efficiency, solar efficiency, and expandability (with the least economic hit in the future), I would very much like to get either the Renogy 280w 24v panel or something compatible to start (based on what I've read from others experience the monocrystaline is good for efficiency, but the poly is better if the sun goes dark momentarily or with intermittent cloud cover). The panel is 64.5in in length and 39in wide. With the future in mind, I would really like to be able to have two panels mounted lengthwise across the width of the van.
Here's the problem I'm seeing with that:  most roof racks have the feet at each end (to keep stuff from falling over the edge) and they curve inward a bit. I haven't specifically measured my roof from gutter to gutter, but I suspect it is right at 65in or pretty close. I don't have my van at the moment so cannot verify.  

Question I have: has anyone else installed this size panel with the length going along the width of an e350? If so, we're you able to have it work with a standard ladder rack or did you have to spend more on a rack that didn't have the end feet? Or did you attach directly to the van (I really dont want to do that though). Or did you install along the length of the van (two panels)?

The reason why I feel the feet on the roof rack would be an issue is if I use the bed frame concept to mount, the panel would be too long to get the frame in between the feet. But I guess it could also be installed with wood slats as cross members instead.

I already know 100 watts just isn't going to cut it for me and the roof of my van will fit 3 panels, but then I don't think I'd be able to have ventilation up there (unless the rack lifts the panels high enough - which reduces aerodynamics further as well as stealth) and I find it troubling to spend a third more for 240 less watts.

I understand I will need to get a more expensive controller and I'm fine with that as long as I have the most economical and expandable system from the start (that works for my van).

I'm trying to use the KISS principle here, but also being quite honest with my needs/desires at the start.

I am also trying to get all these things purchased soon so I may utilize the resources at the build event to help with install and work out any of the kinks.  

I appreciate any advice or thoughts or pics or....

 

[frater secessus]

200w of solar works great for a lot of people.  It's the most common scenario here on the forum.

My panels are mounted side-to-side on my van because they fit best that way:


The end posts/feet will cause two separate problems:

1. fitment, as you pointed out; and,
2. power-robbing shadows on the cells

I would consider either cutting off the feet and mounting the panels flush, or trading racks with someone who is footless and wants rack feet.  A picture would help us understand what you're up against.

BTW, I think you found the forum's largest font.  I thought I had a stroke there for a second. 

 

[jimindenver]

To the OP.

24v panels up to 270w are generally 39x64. The next step up in the 300w plus range are 39x77. The monster on my truck is 435w and measures 41x81. There are exceptions but these are the general measurements. I can say that at the RTR I saw a van with 1000w on its roof.

 

[HumbleBeginnings]

So... regarding mounting solar panels on the van:

My thought is, install gutter-mount cross bars (vs a full rack) further apart than the size of your panels. Then, attach some aluminum angle in-between them, lengthwise with the van (something like this). Then mount your panels to that.

I haven't done it yet, but I bought these cross bars to mount my panels to. In my case I'm not planning to use panels that big, so the plan is a little different. If you need a little more rigidity due to the length between the bars, maybe use steel instead of aluminum.

 

[rm.w/aview]

Find Waldo... or in this case the small handful of posts that actually addressed the OP.

 

[rm.w/aview]

Find Waldo... or in this case the small handful of posts that actually addressed the OP.

this one should be deleted with the others that it referred to, thanks

 

[rayrey]

I agree. So I have removed all off topic post. There is a thread that deals with the workings of a MPPT controller and which company was best was not in the original post. I will send PM's to all who's post were removed.

 

[John61CT]

I hate the look of gutter mounted

RhinoRack and Yakima make some very low-profile 'feet and crossbar' systems for literally any type and size of roof.

The "track" style lets you move your crossbars forward/back as needed, and except for some vehicles, attach with PlusNuts.

Once you get used to the PlusNuts idea though, I think you can save a lot of money DIY.

Whatever you do, if the vehicle's going to last more than a few years, make it flexible enough that you can swap out to another size of panels down the road.

 

[jimindenver]

Expand-ability is the one area PWM has it over MPPT. With MPPT the panels need to match up which may be a right pain in the butt even just a few years down the road. PWM can take multiple sized panels meaning you have less hassles expanding or filling those little spaces that could be producing power.

 

[John61CT]

With cheap controllers you have the same flexibility, 1:1 right-sized per panel.

Minimum issues with shading as a bonus.

MPPT on a chip embedded right into the panel would be nice.

 

[rm.w/aview]

I purchased a Yakima rack nearly 20 yrs ago, still in service. I've had it on 4 different vehicles using the appropriate Towers per vehicle, (gutter mount, gutterless mount, factory rack mount, and factory cross bar mount). The Yakima crossbar/tower combo is low profile, (nicely carried 4X8 sheets on top of the wagon), and the design allows you to go long on the crossbars as necessary to add more usable surface, and being round (essentially coated 1" pipe) allows for fastener options as well. At one point I did know what the load limit is on my system and have stayed below the max limit. I don't have that info now, but I can say that I've safely carried lumber, drywall, bar stock, boats, and bikes on top with no issues, so I believe it more than capable to meet your needs.

 

[MikeRuth]

I did mine like this....

 

[HumbleBeginnings]

I think the OP's problem is that his panel will be wider than those vertical end pieces shown in the pic above.

 

[John61CT]

The Yakima feet allow you to use as wide a crossbar as you like

 

[DLTooley]

I’m still educating myself on this same upgrade path. Please check my assumptions. Mppt is still a benefit at 12v as you capture the difference between the charge voltage and actual panel output. You do have some flex with a mppt system. For example the Victron will accept up to 75 volts. (Is that a 48v system?). If you have 100 watt panels already that is an easy upgrade path. I have an older 50 watt and I will keep the current cheapo controller for that, operating separately

 

[John61CT]

Actual max volts might be 68 to be safe.

No matter the incoming voltage, gets converted to whatever the bank wants, auto senses either 12 or 24

 

[lifemonkey]

BTW, I think you found the forum's largest font.  I thought I had a stroke there for a second. 

Sorry! I did a copy/paste on my phone and didn't realise it wasn't going to default the font automatically.  :}

I really like how you mounted those panels. I was thinking I would be putting the panels on top of the actual crossbar, but yours is flush and looks much nicer. 

I just got back in town and got my van today and measured the width from gutter to gutter which is 63.5in.. the Yakima crossbars are 66" in length, so I think using the angle irons like you have to bring the panels down lower and flush with the crossbar would work out just fine.  The 24v panels are 64.5" x 39" and I have about 125" of roof to play with, so I don't think fitting two panels lengthwise will really work (at least not with angle irons flush like that) . But having them side by side across the width of the van, I'd be able to fit 3 panels snugly. Just no room for a vent... 

why do you have to angle beams butt up against each other? Or is one of them a shorter bracket at the bolt points?

 

[lifemonkey]

So... regarding mounting solar panels on the van:

My thought is, install gutter-mount cross bars (vs a full rack) further apart than the size of your panels. Then, attach some aluminum angle in-between them, lengthwise with the van (something like this). Then mount your panels to that.

I haven't done it yet, but I bought these cross bars to mount my panels to. In my case I'm not planning to use panels that big, so the plan is a little different. If you need a little more rigidity due to the length between the bars, maybe use steel instead of aluminum.

Hi Humble - Those are actually the same cross bars I bought before I realised the dilemma of the feet getting in the way of the length of the panel. They'll be coming tomorrow, but I plan on returning them, because I prefer the look of the Yakima's better.

 

[lifemonkey]

I think the OP's problem is that his panel will be wider than those vertical end pieces shown in the pic above.

Yes, that is correct. The width of my roof is only 63.5" with a Yakima crossbar being 66" or 78" is there longest for my vehicle. Either way, I'd not be able to fit two panels side by side on their width side, since the width is 39". I think length along the width of the panel has the better fit.

 

[lifemonkey]

The Yakima feet allow you to use as wide a crossbar as you like

Hi John - the only problem I am seeing is the tracks - the longest Yakima has is 54" with the plusnuts. I'd have to get two sets in order to go the full length of my roof in order to install two panels. The track system also didn't come up as a selectable option for my van - only the gutter mount towers (which I am fine with as long as there are no feet that extend up). I would imagine the track system can be installed on pretty much anything, but just not sure why it didn't come up - unless they are phasing them out of existence.