Vertical solar panels

[Oneleggedcowboy]

Hello I am back from the grave so to speak. Lost another leg in Az last year. Getting over that.

So my question is...
I am unable to get on the roof of my motorhome to put more panels up there. So I was thinking about mounting light weight flexible solar panels on the vertical sides? They would never have to flex.

Second question would be their efficiency compared to flat roof? I would not tilt them on either the roof or sides.

I forget how to notify a member but a big shout to Jimindenver. He has got me thru a bunch of solar projects!!!

 

[rruff]

Sorry to hear about you losing another leg, but glad that you are still at it!

Assuming you have no shading and a clear horizon, in summer an east or west facing vertical panel should collect about half what the one on the roof does. In winter they will all collect less, but I think the east and west panels would relatively be better than half the top. Vertical south would do pretty well in winter (better than top, east, or west), but very poorly in summer.

 

[frater secessus]

I was thinking about mounting light weight flexible solar panels on the vertical sides? They would never have to flex.

I've seen it done before after roofspace was maxxed.

Second question would be their efficiency compared to flat roof?

My WAG is the vertical panels could collect more light than horizontal flat-mounts when:

• facing south; and
• when the sun is less than 45deg over the horizon

Horizontal panels would make Bonus Power when positioned near reflective surfaces like snow, water, white structures, etc.

A complicating issue is that less power is harvestable when the sun is lower in the sky because the sunlight is traversing more light-dispersing atmosphere. Same reason sunset/sunrise are dimmer than noon and have pretty colors.

Better than nothing? Yeah, especially in winter and/or higher latitudes. Worth the cost of the panels, separate controller, and needing to park in one cardinal direction? I dunno. If the RV is moved semi-regularly some form of alternator charging might be easier and more cost-effective. Or maybe an auto-starting generator.

If you pull the trigger please share the results for the benefit of us onlookers.

 

[Oneleggedcowboy]

I was hoping for a reply from someone that did it.
Thanks for the info so far.

 

[Tom_M]

I have one fixed panel on the roof and the others are mounted on the side. The side panels can be tilted up or they can be removed and set out in the sun.

 

[rruff]

I was hoping for a reply from someone that did it.
Thanks for the info so far.

It's just geometry. It'll depend on your latitude, time of year, orientation, panel characteristics, topography and trees, etc.

Like I said they'll do well in winter if they are facing south. In summer they should be on both sides (facing east. west), with your rig pointed south or north.

If you are parked in one spot for awhile, a portable panel that you can orient however you like, and remotely from your rig, is a good thing to have.

 

[Oneleggedcowboy]

I have one fixed panel on the roof and the others are mounted on the side. The side panels can be tilted up or they can be removed and set out in the sun.

Wow how much solar do you get when vertical

 

[ianganderton]

This calculator will help see the actual differences in numbers

http://www.solarelectricityhandbook.com/solar-irradiance.html
You can set a range of different panel orientations for locations all over the world

As an example here are the numbers for Phoenix for flat and south facing vertical

 

[Oneleggedcowboy]

This calculator will help see the actual differences in numbers

http://www.solarelectricityhandbook.com/solar-irradiance.html
You can set a range of different panel orientations for locations all over the world

As an example here are the numbers for Phoenix for flat and south facing vertical

View attachment 29713
View attachment 29714

Now that's what I call incredible info!!! Thanx a bunch!!

 

[Tom_M]

I did a test yesterday with my 85 watt panel. With it pointed directly at the sun I got 3.6 amps. With it positioned vertical on the side of my coach I got 3.2 amps. Sky was crystal clear and no clouds. I'm located in central Florida.

 

[Oneleggedcowboy]

Thanx for the real life info.