Thread Tools Search this Thread Display Modes
Old 08-20-2011, 03:36 PM   #1
4 Rivet Member
UAPachyderm's Avatar
2004 28' International CCD
Birmingham , Alabama
Join Date: Sep 2007
Posts: 323
Solar Panels Provide Shade - Fact or Fiction?

Multiple users have posted that solar panels provide shade. I think there is some logic to this idea; however, the panels also absorb heat and might have the opposite effect. Has anyone seen any empirical data to support the notion that panels shade or cool the roof?

UAPachyderm is offline   Reply With Quote
Old 08-20-2011, 04:29 PM   #2
Rivet Master
2005 19' Safari
Phoenix , Arizona
Join Date: Aug 2004
Posts: 2,359
I don't know if this counts as impirical data, but we used to carry a 16-foot jon boat on top of a passenger van. Before we started carrying the boat, that van was very hard to cool with the air conditioner. However, with the boat loaded on top of van, it was noticeably cooler than without. You could feel the difference in temperature by placing your hand to the roof of the van.

Therefore, I would guess that this would also apply to solar panels. However, our 19-foot Bambi doesn't have much free space on the roof; and the limited power provided just isn't cost effective for us.

I guess we could buy a bigger Airstream, so that we could get solar panels to power all of the stuff we could then pack in it. However, our 19-foot fits our needs; and we already have a generator.

Some people say that some generators make a lot of noise; but when we're boondocking, the only people around are us...

Phoenix is offline   Reply With Quote
Old 08-20-2011, 04:51 PM   #3
Rivet Master
jdalrymple's Avatar

2009 27' FB Flying Cloud
1991 35' Airstream 350
Siloam Springs , Arkansas
Join Date: Oct 2006
Posts: 1,491
I have some experience in the wireless communications business. We sometimes used aluminum cabinets to house equipment at tower sites.
Most manufacturers of these cabinets offer shading panels to be affixed to the top and sides of the cabinets with 1” standoffs. They are simply aluminum sheets, sometimes with the edges bent at an angle for a little rigidity. These added panels decrease the temperature inside the cabinet a noticeable amount.

Jeff & Cindy
Hunter RIP

'09 27FB Flying Cloud
'91 350 LE MH
jdalrymple is offline   Reply With Quote
Old 08-20-2011, 05:39 PM   #4

2003 25' Classic
Zanadude Nebula , WNY
Join Date: Jun 2007
Posts: 10,802
Images: 1
On the next Sunny day just put a thermometer under the panel.....or, use an infra-red and take the surface temp under the panel and compare it to an exposed area. Would be interesting to find out.

I have flexibles that lay directly on the aluminum and they do get very hot in direct sun.
AF #1

"Sticks & stones can break your bones...and hail will dent your Airstream"

So when is this..."old enough to know better" supposed to kick in?
ROBERT CROSS is offline   Reply With Quote
Old 08-20-2011, 07:21 PM   #5
4 Rivet Member
UAPachyderm's Avatar
2004 28' International CCD
Birmingham , Alabama
Join Date: Sep 2007
Posts: 323
Interesting about the boat and the aluminum shading panels. I don't keep an infrared on me, but I might have to give the thermometer test a shot. Thanks for the responses. It seems that some manufacturer or installer would have measured this already ... maybe not.
UAPachyderm is offline   Reply With Quote
Old 08-20-2011, 07:31 PM   #6
DKB_SATX's Avatar

1975 Argosy 24
1976 Argosy 28
Alamo Heights , Texas
Join Date: Aug 2006
Posts: 5,716
Images: 1
Blog Entries: 7
Shading the roof from direct solar radiation would definitely make a significant difference. The way it would be done in reality wouldn't provide 100% of the benefit of keeping the sun off, since some heat would transfer to the trailer through the supports of for the panels, some waste heat would radiate from the underside of the panels, etc. but if there's air circulation under the panels I'd guess the shade effect would be significant, at least per area it shades.

Il Carriaggio 1975 Argosy 24 | Il Progetto 1976 Argosy 28 Center Bath | WBCCI# 15566

He has all of the virtues I dislike and none of the vices I admire. Sir Winston Churchill
DKB_SATX is offline   Reply With Quote
Old 08-20-2011, 08:21 PM   #7
4 Rivet Member
steverino's Avatar
2010 27' FB Flying Cloud
Ivins , Utah
Join Date: Aug 2009
Posts: 261
Images: 3
My 3 100W solar panels occupy 17.6 square feet of the approximate 200 square feet roof area of the Airstream, or about 9%. I do not expect a discernible difference in overall heat transmission through the roof due to the presence of the panels. With more roof coverage, yes, due to the insulating effect of the layer of air between the panels and the roof, as in jdalyrmple's example.
steverino is offline   Reply With Quote
Old 08-20-2011, 08:35 PM   #8
3 Rivet Member
Erik Olson's Avatar
1974 29' Ambassador
CONCORD , North Carolina
Join Date: Aug 2011
Posts: 179
Images: 20
Send a message via Skype™ to Erik Olson
The Series I Land Rovers of the late 50's added a second full-roof panel that was held proud above the primary roof on small risers. The primary roof was vented. These Safari Roofs certainly make a difference and I suspect your solar panels could, despite their obvious solar gain properties, actually cool the skin of the trailer.
Erik Olson
1974 Ambassador 29' Ohana
Erik Olson is offline   Reply With Quote
Old 08-20-2011, 09:07 PM   #9
Rivet Master
mandolindave's Avatar
Join Date: Jan 2004
Posts: 2,089
Images: 4
It might be a fun thing to do at a Rally.

Recruit two of the same size campers, put a thermometer in both of them of them. Put three panels on one camper and none on the another.
I would be interested in the results.

I don't know if it is an urban myth, but I heard that they painted the roofs
of school busses white because it made them 12 degrees cooler.
mandolindave is offline   Reply With Quote
Old 08-21-2011, 12:53 PM   #10
Rivet Master
Silver Goose's Avatar
2008 27' Classic FB
Burkburnett , Texas
Join Date: Jul 2010
Posts: 955
The roofs on recent Airstream models come from the factory in white...

My AS is currently parked under a white metal carport. The trailer is closed up except the roof vents are open. Ambient temperature outside is 103, roof on AS measures 108 with an IR thermometer, carport surface measures 120.

It would seem reasonable that solar panels with an air gap above the roof would deflect some of the solar gain, but as previously stated, the small fraction of the roof that is shaded by the panels is probably insignificant. I like the idea of using two identical trailers parked side by side and measure the difference.
AIR 47751
Air Safe Hitch, Reese Dual Cam 800#, Centramatics
Silver Goose is offline   Reply With Quote
Old 08-21-2011, 01:26 PM   #11
2 Rivet Member
Currently Looking...
Hillsboro , North Carolina
Join Date: Mar 2011
Posts: 26
It's the airspace that counts

As long as you can get at least 1" of circulating air and the brackets are either minimally conducting (of heat, e.g. aluminum or have some sort of stand off insulation--hard rubber gasket would do it) you are going to have an at least minimally cooler roof.

Depends on how much of the roof you can cover.

Take a look at any US building code book (good example: heat shielding for woodstoves) and you can see how effective that 1" can be.

Airspace is your insulating friend, always.
TinCanLand is offline   Reply With Quote
Old 08-21-2011, 03:18 PM   #12
1 Rivet Member
1968 24' Tradewind
St. Pete Beach , Florida
Join Date: Aug 2011
Posts: 5

my boat has 2 50 watt solar panels on an arch, I stay cooler when I sit in their shade, so your trailer will too. The air gap is imperative to the panel cooling, as panel temps rise, output decreases.

blubadub is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
What solar panels to buy? GaRoc Boondocking 45 10-09-2011 07:15 PM
Solar Power for Battery Maintenance Tumajin Generators & Solar Power 10 08-12-2011 06:10 AM
Solar panels Marilynperl Generators & Solar Power 6 05-27-2011 09:21 AM
Solar Power Quandary for my '58 mello mike Generators & Solar Power 7 04-06-2011 08:05 PM
Solar Panel Prices Dropping tbro Generators & Solar Power 11 03-30-2011 08:21 PM

Virginia Campgrounds

Reviews provided by

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 01:18 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.