Flexible Solar Panel Recommendations

[FreezingMan]

I'm looking for recommendations for flexible solar panel(s) to install on my camper. Many of the Amazon ones seem questionable. This Lensun 200W panel seems like a good fit. Has anyone installed this panel? Any other suggestions or recommendations for panels? I'm trying to go with a lightweight panel to minimize the difficulty of raising the camper roof.

https://www.lensunsolar.com/Products/Flexible-solar-panel?product_id=770

Here's my configuration, I have a 2014 Fleet sitting on top of a 2014 Tacoma. After my AGM batteries failed I'm upgrading the batteries to a LiPo 100Ah BB battery, adding DC2DC charger, battery monitor, upgraded wiring, and finally a solar package. The AGM batteries always met our needs until the last year or so. They were installed 2014. Combined they were rated for 150Ah. Now they don't hold a charge. We have a 3 way fridge, propane heat, water pump, and LED lights. All FWC supplied.

 

[lostcreek]

I have been using a high-quality flexible panel from Global Solar for 6 years, 2 100W on the aluminum roof; very durable, scratch resistant, still outputting almost like new. But it appears that they are no longer available (like several other equivalent brands). Looked at the specs you linked for Lensun and they seem quite attractive, prob. better than mine. A big step up from the inexpensive ones that are available everywhere else. (BTW I have one of those cheap ones too, in parallel with the Global Solars - they work OK and last 3 years or so.) For flexible panels I let price be my guide - more of a niche market and they seem to come in two tiers, low quality (many choices) and high (few choices).

As for installation, mine came with adhesive backing. I'd go with whatever Lensun recommends for your roof type.

 

[Ted]

The rooftop glue down panels on our Provan Tiger are covered in a textured, clear plastic that provides a non-slip grip for walking on but does not affect their energy production. yes, you can actually walk on them. We have 400 watts of solar and our lithium batteries are usually fully charged by noon. Not sure of the brand as they came with the rig, but you can contact Provan Tiger Adventure Vehicles in S. Carolina and ask. Jay is the main service guy there.
Whatever you end up with, you will be very happy with the switch, Going from AGM to Lithium and upgraded wiring is a night and day difference. We constantly struggled with a lack of power in our FWC. Almost 200 nights in our Tiger now and the lowest I have ever seen the batteries is 12.9.

 

[Jack]

Our HQST panels have done us well. We mounted them with 2" velcro strips along the sides. This keeps the panel off the roof with a 1/4" gap that may be of some thermal help.The panel front corners have a piece of roof repair tape to anchor them to the roof. This leaves a gap to allow air flow at least while driving. The velcro also makes it quite easy to replace the panel if necessary.

Ted is right on with lithium. The battery in our Fleet front dinette is in the left rear corner - a colder space that in many other FWC configurations, but this has not been a problem for us in freezing weather. There are a number of discussions on WTW about lithium in cold weather, and there are heater jackets for really cold (sub-zero) weather.

 

[Stokeme]

https://www.expertpower.us/collections/solar-panels/products/100w-sunpower-solar-panel?variant=32044189581410
Use CSEEKER for 5% discount coupon code. Sunpower panels.
They don’t have the 110W Hi-E panels anymore but they were $30 more too. I’d call & make sure you won’t be delivered any previously returned panels. Always a concern for me. (Re-Amazon returns going back out again) Expert Power is more direct. I think Sunpower makes the best Flex cells, they sell their cells to many others. The best Flex panel probably does not last as long as glass but the EFTE exterior helps with longevity a lot. The roof weight was critical for me. Sunpower includes a good quality junction box. Lensun are good panels, seriously considered years ago, not sure now about the black surface. You might want to look for reviews. Check out Will Prowse on YouTube or his webpage, or other YTubers.
Get a Victron Solar Controller, a 100/20 or 100/30, Smart Bluetooth version. It’s perplexing, BB does not install internal BT monitors. You should know, & be able to manage, your SOC. Trying to manage your system through your V is nebulous. Invest in the BT shunt below. Use your phone BT app for system wide info & settings. My suggestions, happy hunting.
https://www.amazon.com/gp/product/B0856PHNLX/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

[buckland]

I have had the Renogy 100 Watt for a few years and it is great at 4 pounds. I use it a my cab windshield sunshade on an extension cord. Nice extra juice. Here is a 175Watt but look around great holiday sales

https://www.amazon.com/Renogy-175-Watt-Volt-Monocrystalline/dp/B082FCZ4MD

 

[CPT Davenport]

I have had the Renogy 100 Watt for a few years and it is great at 4 pounds. I use it a my cab windshield sunshade on an extension cord. Nice extra juice. Here is a 175Watt but look around great holiday sales

https://www.amazon.com/Renogy-175-Watt-Volt-Monocrystalline/dp/B082FCZ4MD

I have been running Renogy panels and other products of theirs for over 10 years now with great success. I have the above mentioned panel on my hawk and it keeps my 206ah lithium pretty happy. I rarely need to break out my 130w folding panel for back up. The 175w is light weight and good quality. My only issue is when I have a surfboard on the racks it covers about 2 feet of the panel. This brings the incoming watts WAY down to next to nothing. This seems to be more of an issue for this panel compared to any other panel I have previously had partially covered. All in all, it does a great job for the size and weight. I mounted it to my Yakima tracks with a home made, aluminum frame.

 

[ckent323]

As far as I am aware the all solar panels including flexible panels are recommended to be mounted with a minimum of 1 inch air gap under them. The back side of all solar panels gets very hot and the heat needs to be conducted away. If the heat is not conducted away hot spots can develop which degrade or damage the panels shortening their life.

The paint on the Aluminum roof or our campers is not conductive paint and most of the adhesives that are used are also non-conducting. Therefore, it is best to mount flexible panels on a frame that provides the air gap.

Caveat emptor

I hope this is helpful


Craig

P.S. I mounted a single 360 watt LG panel on our camper roof with 1 inch air gap. We also have a Sun Power 100 Watt semi-flexible panel that was used on our sailboat before I moved the two 100 W GRape Solar panels that were on the camper over to the boat. The semi-flexible panel has always been supported in a manner that ensures there is plenty of air space behind it. So far no issues.

 

[DavidGraves]

Hi Craig

My solar flex panel stalled partly because we just don't need solar charging with our mode of camping.

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 ?

I wanted flex panels mostly for their light weight.

David Graves

 

[rubberlegs]

I've been thinking about flex vs rigid panels too. Our needs are 100-200W (we "currently" do ok with 90W, and I hope that comment isn't too "revolting"), so I was considering two 100W flexible panels at about $150 each. Two so that we have some redundancy in case of panel failure. This reduces weight and drag. The weight is more of a factor lifting the roof, but the drag affects gas mileage.

Say one of the panels is cooked and fails in three years. Could I save $150 in gas if I had a panel failure? I'm not sure how much drag difference there is between a rigid panel (or flex panel with a gap) and a flex panel bonded to the roof.

Hmmm..... It's fun overthinking this stuff!

 

[rubberlegs]

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!

 

[JaSAn]

. . .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.

 

[camelracer]

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

 

[DavidGraves]

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

 

[ckent323]

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

 

[buckland]

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.

 

[CPT Davenport]

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.

 

[rubberlegs]

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.

 

[rubberlegs]

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.

 

[nebosllin]

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.