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Flexible Solar Panel Recommendations


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#11 rubberlegs

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Posted 28 November 2022 - 05:14 PM

I had planned (and created) to rest the panels atop 1" blue foam panels in which I drilled a regular panel of 4" diameter holes along with fore aft air channels.

 

I  know the foam is not a heat sink but do you think the amount of air in the holes would offset heat damage ?

 

The thermodynamicist in me thinks this isn't a great idea. The blue foam is a really good thermal insulator. So you'd have hot spots where there's foam, and cool spots elsewhere. If the panels have good thermal conductivity (I have no idea), it might be ok though.

 

The aerodynamicist in me says put the panels as far aft on the roof as possible, so they are in the thicker boundary layer. The solar designer in me says "will there be more shade on that end? Probably not."

 

All of this is pure theory, and possibly wrong!


Edited by rubberlegs, 28 November 2022 - 05:15 PM.

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#12 JaSAn

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Posted 28 November 2022 - 07:47 PM

 . . .The weight is more of a factor lifting the roof, but the drag affects gas mileage . . .

Combination of struts and speaker lift makes lifting the roof with rigid solar panels a non-issue.

 

I have a 100W rigid panel located 1.3 inches above the roof and 8 inches back from the front edge of an FWC Grandby.  The windshield/front of camper pushes air over the panels; no decrease in gas milage.


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#13 camelracer

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Posted 28 November 2022 - 08:05 PM

I had 2 Lensun 100W aluminum substrate panels fail after a couple of years. I wouldn't recommend that company.


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#14 DavidGraves

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Posted 28 November 2022 - 11:47 PM

All this thinking is good for the little grey cells.

 

In reality for us we could just store the lightweight flex panel on the overhead bunk area (which we don't use) and deploy

on the truck windshield at 45 degrees to our sun here along the 45th parallel above the equator....but here is still that darn heat.    

 

David Graves 


Edited by DavidGraves, 28 November 2022 - 11:48 PM.

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#15 ckent323

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Posted 29 November 2022 - 12:19 AM

David,

I don't know what temperature the blue foam can tolerate but I would be concerned that the panel may get hot enough to partially melt it.

Further, as rubberlegs mentioned above, foam is an insulator and even with holes in the foam the areas where the panel contacts the foam will get hot and that heat will not have a good path out (BTW: heat flows from hot to cold). I am not certain what will happen but my sense is that it may not be a good idea.

I have seen semi-flexible panels mounted onto fames similar to those used for rigid panels which are in turn mounted to the RV or camper or boat roof with a minimum of 1 inch air gap and they seem to work well.

I have read too many stories of people directly adhering panels to the roof of an RV or camper using consumer adhesives or VHB tape (which are almost all non thermally conducting) and then having a heck of a time scraping everything off when the panel fails. I think it would be better to mount semi-flexible panels similar to a rigid panel. Indeed, I have seen some semi-flexible manufacturer recommendations to mount them with minimum of 1" air gap.

I hope this is helpful,


Craig

Edited by ckent323, 29 November 2022 - 05:54 AM.

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#16 buckland

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Posted 29 November 2022 - 12:24 AM

All this thinking is good for the little grey cells.

 

In reality for us we could just store the lightweight flex panel on the overhead bunk area (which we don't use) and deploy

on the truck windshield at 45 degrees to our sun here along the 45th parallel above the equator....but here is still that darn heat.    

 

David Graves 

I put my windshield wipers up then rest the panel them. 


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#17 Cpt Davenport

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Posted 29 November 2022 - 02:19 AM

 

I have seen semi-flexible panels mounted onto fames similar to those used for rigid panels which are in turn mounted to the RV or camper or boat roof with a minimum of 1 inch air gap and they seem to work well.   
 

 

 

Craig

 

 

This method produces more watts at a much lighter weight.

 

100w Renogy rigid panel on my cabin = 14+ pounds

 

175w Renogy flexible/with homemade frame on my Hawk = 7 pounds

Considerably more watts for 1/2 the lbs.

 

No mess with removal of adhesive from roof if the panel fails or you wish to change configuration. 

No worry of overheating damage to panel

Also provides a lower profile than rigid panels

 

Anyone with some aluminum z bar, flat stock, a cheap rivet gun and a drill can make a suitable frame for a flexible panel. I modeled mine after the panels I saw in the FWC showroom while I was waiting for my install. 


Edited by Cpt Davenport, 29 November 2022 - 02:24 AM.

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#18 rubberlegs

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Posted 29 November 2022 - 10:26 PM

I kinda like the idea of putting a flex panel on the windshield, except you have to park the truck pointing south. For non-windy camping you can put it on top of the camper, and hope it doesn't slide off while raising the top. Maybe a little bit of velcro glued to the roof would work in a lighter wind. But put it inside while driving. Then the heat issue may not be a big deal, unless you are a full-time camper, because the solar panel wouldn't be in the sun 365/24/7. So the panel may last quite a few years.


Edited by rubberlegs, 29 November 2022 - 10:35 PM.

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#19 rubberlegs

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Posted 16 September 2023 - 06:50 PM

We have less than a year's usage with our flex panel. Output about half-- wow, that's a lot. Is yours permanently mounted on top?

 

Ours doesn't calculate to its rated 100W in our sun conditions. But it easily keeps our battery charged up, since our usage is pretty low.

 

We stow it under our mattress, pretty handy compared to our heavy and bulky suitcase panel. But we've not had heavy winds yet. That could be a big issue not driving for 3 days.


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#20 nebosllin

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Posted 25 December 2023 - 02:34 PM

I have 300w 12v solar panel that is almost three years old and it's output is about half from when it was new. Excellent Product, never thought that solar panels could be so soft and thin.


Edited by nebosllin, 26 December 2023 - 07:48 AM.

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