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solar pannel mounting: luggage rack mount? [message #123267] Tue, 26 April 2011 10:23 Go to next message
Duce Apocalypse is currently offline  Duce Apocalypse   United States
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I was wondering, I never use the lugage rack mount on my coach, but it looks like it might be a perfect spot to sling some PV pannels across. has anyone tried a setup like this? it would also allow air to pass under the panel which would allow for cooling on a hot day, and would partially shade part of the roof...

some advantages of a luggage rack mount would be: ability to mount hight wattage large panels laterally, looks like with a little though one could get 5.5 foot panels slung across the bars with little work. No need to drill additional holes in the roof, rack is already there, simply run wiring connections down the nearby fridge vent. The ability to remove panels for storage. relitavely low drag. pleanty of air gap for panel ooling and increased shade on rooftop reducing coach heating in summer...



73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA

[Updated on: Tue, 26 April 2011 10:42]

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Re: solar pannel mounting: luggage rack mount? [message #123291 is a reply to message #123267] Tue, 26 April 2011 13:47 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
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Duce Apocalypse wrote on Tue, 26 April 2011 08:23

I was wondering, I never use the lugage rack mount on my coach, but it looks like it might be a perfect spot to sling some PV pannels across. has anyone tried a setup like this? it would also allow air to pass under the panel which would allow for cooling on a hot day, and would partially shade part of the roof...

some advantages of a luggage rack mount would be: ability to mount hight wattage large panels laterally, looks like with a little though one could get 5.5 foot panels slung across the bars with little work. No need to drill additional holes in the roof, rack is already there, simply run wiring connections down the nearby fridge vent. The ability to remove panels for storage. relitavely low drag. pleanty of air gap for panel ooling and increased shade on rooftop reducing coach heating in summer...




Shan,

Here are a couple of pics of Dan Winchester's coach with the solar panel mounted on the luggage rack. I was just taking general photos of the coach at the time, so these are not specific to the panel mounting, but still visible.

http://www.gmcmhphotos.com/photos/showphoto.php?photo=38839&title=dan-winchester-27s-coach&cat=5770

http://www.gmcmhphotos.com/photos/showphoto.php?photo=38836&title=dan-winchester-27s-coach&cat=5770

With no rear AC, there was plenty of room. He said it was a 130 watt panel and he claimed to be getting 8 amps out of it.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: solar pannel mounting: luggage rack mount? [message #123306 is a reply to message #123291] Tue, 26 April 2011 16:35 Go to previous messageGo to next message
Duce Apocalypse is currently offline  Duce Apocalypse   United States
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Carl,

Good pix, my idea was something similar to that, but I was thinking of larger panels and slinging them laterally. I have no rear AC and with some mounting rails attached to the rack would still alow for some clearance to open the maxx air vent at the rear. The way I figure it there could be room for up to 675w of panel for the models I was loking at. That's some serious solar. The 8 amps for a 130w panel seems pretty spot on from what I've seen. I think the biggest challenge though will be finding room for enough batteries to hold that power. Currently I have about 250aH which means 125 assuming a 50% drain is usable. One of the 215w panels would be enough to start with the idea to grow to more as I can afford. I can get a panel for about 350 so that's what got me thinking how to do this...

Quote:

title=Carl S. wrote on Tue, 26 April 2011 13:47]
Duce Apocalypse wrote on Tue, 26 April 2011 08:23

I was wondering, I never use the lugage rack mount on my coach, but it looks like it might be a perfect spot to sling some PV pannels across. has anyone tried a setup like this? it would also allow air to pass under the panel which would allow for cooling on a hot day, and would partially shade part of the roof...

some advantages of a luggage rack mount would be: ability to mount hight wattage large panels laterally, looks like with a little though one could get 5.5 foot panels slung across the bars with little work. No need to drill additional holes in the roof, rack is already there, simply run wiring connections down the nearby fridge vent. The ability to remove panels for storage. relitavely low drag. pleanty of air gap for panel ooling and increased shade on rooftop reducing coach heating in summer...




Shan,

Here are a couple of pics of Dan Winchester's coach with the solar panel mounted on the luggage rack. I was just taking general photos of the coach at the time, so these are not specific to the panel mounting, but still visible.

http://www.gmcmhphotos.com/photos/showphoto.php?photo=38839&title=dan-winchester-27s-coach&cat=5770

http://www.gmcmhphotos.com/photos/showphoto.php?photo=38836&title=dan-winchester-27s-coach&cat=5770

With no rear AC, there was plenty of room. He said it was a 130 watt panel and he claimed to be getting 8 amps out of it.



73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
Re: solar pannel mounting: luggage rack mount? [message #123393 is a reply to message #123306] Tue, 26 April 2011 21:56 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
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Duce Apocalypse wrote on Tue, 26 April 2011 14:35

Carl,

Good pix, my idea was something similar to that, but I was thinking of larger panels and slinging them laterally. I have no rear AC and with some mounting rails attached to the rack would still alow for some clearance to open the maxx air vent at the rear. The way I figure it there could be room for up to 675w of panel for the models I was loking at. That's some serious solar. The 8 amps for a 130w panel seems pretty spot on from what I've seen. I think the biggest challenge though will be finding room for enough batteries to hold that power. Currently I have about 250aH which means 125 assuming a 50% drain is usable. One of the 215w panels would be enough to start with the idea to grow to more as I can afford. I can get a panel for about 350 so that's what got me thinking how to do this...




Shan,

That sounds like a great plan. I plan to add solar to our coach as well, but even though I live in a very sunny climate, I will have to do it differently. Here in the Southwest, it is almost a necessity to have two roof ACs. Between those and my storage pod, I will need to be somewhat creative in mounting solar panels. My thought is to get panels the right size to mount on top of my AC units and maybe my pod. I currently use two golf cart batteries for the house system, mounted next to the Onan, but can easily add two more up front. Next step is to get a shunt fed meter so I can tell exactly what's going on. Then add the solar as the budget allows.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: solar panel mounting: luggage rack mount? [message #123413 is a reply to message #123393] Tue, 26 April 2011 22:36 Go to previous messageGo to next message
Mitch is currently offline  Mitch   United States
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I pulled my storage pod off last year to replace the AC. Now I'm looking at that space and thinking. The mounting bolts for the pod are still up there, that would be a great place to put a decent sized panel. Do the frame in the right way and it could even be tip-able to either side for optimum exposure. Plus I could still move around on the roof if I must.
Well, new exhaust first, then we shall see.


Mitch Tacoma, Wa. '80 Spitfire '03 Windstar '77 Jaguar XJ6-C X(very)'76 PB 26 "The Beast" Where it rains, always. It's wet, No sun, Gray. Go to Oregon.

[Updated on: Tue, 26 April 2011 22:37]

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Re: solar pannel mounting: luggage rack mount? [message #123460 is a reply to message #123267] Wed, 27 April 2011 07:57 Go to previous messageGo to next message
Larry C   United States
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Mounting the Solar Panels is pretty much up to the owner but keep in mind the Solar Panel frame is not extremely strong.

In the normal mounting, they are fastened, some are glued, to a firm roof surface. very little flex to affect the panel or panel frame.

You really need to mount on the luggage rack in such a way that there will be no movement. And remember, when the wind is blowing, there are forces on those panels all the time and when you pass a truck, or one passes you like you are standing still, there is a tremendous gush of wind on that flat panel trying to twist it.

Also keep in mind that you need to mount in such a way that you wont put your hand on it or step on it when you go on the roof.

The panel needs to be pretty much inflexible or you can break the panel segments which will ruin the panel.

Are you planning on elevating one side of the panel to aim at the sun? Might be able to create something on the rack to allow that and still retain rigidity. Might be easier to make a frame and use a space blanket to put upright behind the panel to bounce sun onto the panel(s). The more exposure to the sun, the more power is created.

I'm not saying don't do it, its not my place. Just be careful how you mount the panels so there is no twisting or where someone might bump or step into and the winds cannot over power that large flat area of panel.

My thoughts


Gatsbys' CRUISER 08-18-04
74 GLACIER X, 260/455-APC-4 Bagg'r
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CampGrounds needed, Add yours to "PLACES" /> http://www.gmceast.com/travel
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Re: solar pannel mounting: luggage rack mount? [message #123498 is a reply to message #123460] Wed, 27 April 2011 11:06 Go to previous messageGo to next message
Duce Apocalypse is currently offline  Duce Apocalypse   United States
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A good point, rigidity is paramount obviously. I was looking to some different mounting options for the panels I was looking at, and would likely choose the offset mounting which uses 2 support rails under the panel giving 60 PSF load tollerance, or the lateral support mounting option which gives 80 PSF.

Bu being that I am in need of a new radiator and trying to save up for one of jim K's aluminum job, which is a better deal than recoring my own, I will probably have to wait on the panels, but its good to get the discussion out here to the brain trust. Smile

heh if I can sell that lexus I have then perhaps I can afford the panels and the radiator... we shall see...

Larry C wrote on Wed, 27 April 2011 07:57

Mounting the Solar Panels is pretty much up to the owner but keep in mind the Solar Panel frame is not extremely strong.

In the normal mounting, they are fastened, some are glued, to a firm roof surface. very little flex to affect the panel or panel frame.

You really need to mount on the luggage rack in such a way that there will be no movement. And remember, when the wind is blowing, there are forces on those panels all the time and when you pass a truck, or one passes you like you are standing still, there is a tremendous gush of wind on that flat panel trying to twist it.

Also keep in mind that you need to mount in such a way that you wont put your hand on it or step on it when you go on the roof.

The panel needs to be pretty much inflexible or you can break the panel segments which will ruin the panel.

Are you planning on elevating one side of the panel to aim at the sun? Might be able to create something on the rack to allow that and still retain rigidity. Might be easier to make a frame and use a space blanket to put upright behind the panel to bounce sun onto the panel(s). The more exposure to the sun, the more power is created.

I'm not saying don't do it, its not my place. Just be careful how you mount the panels so there is no twisting or where someone might bump or step into and the winds cannot over power that large flat area of panel.

My thoughts



73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
Re: solar pannel mounting: luggage rack mount? [message #123499 is a reply to message #123267] Wed, 27 April 2011 11:14 Go to previous messageGo to next message
Chr$ is currently offline  Chr$   United States
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I'm thinking of mounting two on the rear on each side (front to back) and one up front across the roof (side to side). My Carrier AC units have the Condenser Fan Units on top, so I have limited space up there. I like the idea of using an offset to create space and hence, shade above the coach, but the wind effects at speed worry me, and Larry's comments make a lot of sense with regards to the panel rigidity.

-Chr$: Perpetual SmartAss
Scottsdale, AZ

77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
Re: solar pannel mounting: luggage rack mount? [message #123554 is a reply to message #123499] Wed, 27 April 2011 17:38 Go to previous message
Duce Apocalypse is currently offline  Duce Apocalypse   United States
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Wellgits highly unlikely that in a lateral rail monting you would get a side gust to load up the panel to exceed the 80psf load rating of the panel. If you got cross winds that bad you probably wouldn't want to drive a high profile vehicle...

Chr$ wrote on Wed, 27 April 2011 11:14

I'm thinking of mounting two on the rear on each side (front to back) and one up front across the roof (side to side). My Carrier AC units have the Condenser Fan Units on top, so I have limited space up there. I like the idea of using an offset to create space and hence, shade above the coach, but the wind effects at speed worry me, and Larry's comments make a lot of sense with regards to the panel rigidity.



73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
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