Solar panel mounting

[mhaisten]

Is there a reason that it seems that everyone mounted their solar panels east west? I am thinking of a 4 panel array and mounting north south in the center so that it does not look like a deck mounted up there and have less forward facing surface. I realize the aerodynamics don’t matter as much on a bus.

Another thought is to mount 2 panels all the forward and 2 all the way aft so that if parked with partial shade, you could poke one end out into the sun.

Thoughts?

[Drew Bru]

I don't know how much it matters which orientation they're mounted. Seems like most people mount them for efficiency of space. How you're parked will have as much effect on the panels as how their oriented. Mounting them forward and aft might make sense, on the other hand it could make it more likely that at least one pair would be shaded much of the time. It's so hit and miss for us when we're camped anywhere but the desert. Plus there's the trade-off of shade (for keeping cool) vs. sun (for solar production).

[dzl_]

Originally Posted by mhaisten

Is there a reason that it seems that everyone mounted their solar panels east west? I am thinking of a 4 panel array and mounting north south in the center so that it does not look like a deck mounted up there and have less forward facing surface. I realize the aerodynamics don’t matter as much on a bus.

Another thought is to mount 2 panels all the forward and 2 all the way aft so that if parked with partial shade, you could poke one end out into the sun.

Thoughts?

I'm assuming when you say 'east-west' you mean long side of the PV panels across the bus (port-starboard/left-right) and when you say 'north-south' you mean long side of the panels running down the bus (fore-aft/front-rear).


Since cardinal direction matters for PV panels, its probably clearer to avoid using cardinal directions as an analogy for anything else in this context.


As for how they are oriented on the bus, I think this is situational, depends on panel size, and other factors. Orienting front to rear seems like it can achieve a more low profile install with the tradeoff that one side will always be slightly angled away from the sun.


In terms of the geometry the two most common panel sizes are roughly 66" x 40" (60 cell) and 80" x 40" (72 cell)


A bus is what, 90" or 96" across, but maybe 6" to 12" or a bit more of that on either side is steeply sloped.


It seems for those that install panels across (port-starboard) 60 cell panels are the typical choice, whereas with fore-aft install 60 or 72 cell panels are reasonable.


In the end, I think a lot of it comes down to other factors, do you have roof hatches, or vents, a roof deck or roof rack, etc, and how that constrains your arrangement.


I think both are valid options with tradeoffs, I'm partial to lower profile options.