Want to add Solar panels> What are better the hard, or flexable panels?

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2004CS

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Mar 18, 2017
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I have a 24 Foot Chateau Sport RV. I replaced my one 12v battery with 2 6v batteries. My next project over the winter to add Solar Panels. What type is better Hard or Flexible Panels. Also would like information on what size Invert er and Controller to buy. We will be just charging Phone, Computer, and Camera. Thanks for any help you could provide for me.
 
  Hard!!! Also, do your homework and get some with high wind rating (a heavier constructed frame....you will be driving). They also offer panels with different impact ratings (hail?).  Get the largest you can fit, or several small panels in series. Get the MPPT type (several brands available), more expensive but increases the efficiency of your panels. If your going to travel to different latitudes and different seasons, consider adjustable angle system on your panels. This is how I built mine.
    Sorry....couldn’t get pictures to post. If you want/need more info...call pm me!

    Also, got carried away with array and design for your desires.  Was just on a solar panel sight, conversing with others....and was experiencing “flash-backs”!
 
I would also recommend framed (hard) panels, especially if they're going to be roof mounted. Thin film panels work, and they've come a long way in the past few years, but some users have reported that they tend to settle, and get low spots on RV roofs (especially on rubber roofs.) That causes dust to accumulate in the low spots, which can significantly reduce a panel's output. A similar problem can occur with framed panels, but the dirt tends to accumulate around the edge of the panels and not block as much sunlight.

I also agree with installing as much solar as you can. After all, RVers never complain about having too much solar. However, be careful about putting large panels on your roof, just because they'll fit. They may fit fine, but if they're butted up against a roof AC unit, or a sewer vent, roof vent, antenna etc., shade from those objects can reduce a panel's output to zero - even if only two or three cells are shaded. A lot of people don't know that, and end up with an inefficient system.

RV solar can get expensive, so you certainly don't want to lose any of that pricey power due to installation errors - an all too common problem. Generally speaking, solar is a more practical (I.e. cost effective) solution for those who boondock a lot, especially in areas with a lot of sunshine.

A good MPPT controller will beat a PWM controller any day, but they're also more expensive. You mentioned the devices you'll be recharging, but those aren't the only things that will be drawing your batteries down. TVs, furnace, lights, parasitic loads etc. will all be consuming battery power. IMO, a good battery monitor, like the Trimetric RV-2030, is a must when boondocking, so you'l always know your battery's SOC.

If you normally don't draw your batteries down very far (no less than 70%) a PWM controller should work well on an array of 300 watts or less (ballpark). If you regularly discharge your batteries more deeply, or if your array is more than 300 watts, I'd recommend an MPPT controller - the size of which should be determined by your panel's output.

Kev
 
As Kevin said
It was a couple years ago but I followed a guys blog and he researched flex panels. At the time he said they were having problems with heat not being dissipated as they do when raised off the roof. The other issue is that the panel surface is sort of dimpled and get a little dot of dirt accumulation when dew settles. There may be panels available now that have addressed these issues but that's what I remember of it.

Grape solar makes an MPPT controller for $60 that some have said works fine and iirc is blue tooth to your phone for settings and monitoring. For pwm Bogart engineering makes a ggod one and has good customer service. Morningstar is also good. If you absolutely cant access the roof than you wont be tilting. If there is any safe way for you to get up there and you sit in places for a while you can usually see 25% more power tilted and it's especially helpful in deep winter.  If you can do basic fabrication you can make angle brackets or buy very nice ones from places like AM solar.

I believe the Winns and AM solar did write ups on their flex panel builds. Iirc the guy at AM solar had a massive bank of flex panels on his MH.

With the items you listed you can get by on a pretty small inverter such as a couple hundred watts or less. My laptop pulls 2.4 amps or so at times plus cell etc so you may only pull 5 amps. 5 A x 12.6 volts = 63 watts so a 200 would give you plenty of leeway.
 
Flexible panels are not ideal but being able to glue/caulk them to the roof and walk on them has some advantages.

99% of the R&D goes into fixed panels so these will have a much better watts - squ/ft output.

The name I see Renogy, Zamp and GO Power mention by people looking at low power solar while Magnum and Victron are what full timers mention

We had a 400W GO Power inverter in our TT. With it we could run the TV or the dehumidifier.   

If you are camping in the trees consider portable or a combination of fixed and portable.

Size the wire...go big of go home  ;D  It is easy to loose 5%-10% to poor wiring.

Have you calculated your power consumption?
 
 
Thanks Kevin, Memto, and QZ for your input. Will be trying to locate thick aluminum made panels. Have bad hip will not be going up on roof, so they will just lay flat. Like the idea of a portable solar panel. Did not think about the furnace. Thanks everyone for your input. I saw one of the panel sights where you could put in your 12v usage to determine what watt panels you would need. I will bye everything and make this a spring time project.
 
2004CS said:
I have a 24 Foot Chateau Sport RV. I replaced my one 12v battery with 2 6v batteries. My next project over the winter to add Solar Panels. What type is better Hard or Flexible Panels. Also would like information on what size Invert er and Controller to buy. We will be just charging Phone, Computer, and Camera. Thanks for any help you could provide for me.
Most of the advice given is for someone using much, much more energy that you will be.

With what you state you will be using the battery for, i.e. phone, computer (I assume laptop) & camera, as well as lights, fridge on propane and some propane furnace operation, you don't need much.  Also replace the lights with LED bulbs really helps.

A single 100-150watt panel and a small solar controller.  You don't even need to mount it if you have a place to store it while traveling.  Lots of people carry a panel or two and prop them up on the ground facing the sun to charge their batteries.

A small portable 400watt MSW (Modified Sine Wave) inverter would serve your needs.  If you truly only need the inverter for the computer and it is a laptop you can use a 200watt inverter and just plug it into the 12V cigarette lighter type outlet and it will charge your laptop.  The phone and camera probably can be charged from 12V. 
 
Is there anyway you can add 2 more 6v batteries? I have 4 6v batteries on my fifth wheel and what a difference that made on my ampere hour capacity! It does require a good charging mechanism in place to keep 'em charged up but man you get the capacity then.....
 
Throw my hat into the hard panels for your situation.  The flexible panels are a good option for curved roofs and pop-up style campers, otherwise hard panels are the better bet.
 
Thanks rbrdriver and Gizmo    I only had room for the 2 6v batteries. I think I will just put up 2 hard panel 100 watt panels, controller, and a battery monitor, and a 500 inverter. I will continue to look for a good deal from the major solar companies. Again thanks to everyone for their input. This forum and the people have always provided me the best solution to any problems I have run into.
 
2004CS said:
Thanks rbrdriver and Gizmo    I only had room for the 2 6v batteries. I think I will just put up 2 hard panel 100 watt panels, controller, and a battery monitor, and a 500 inverter. I will continue to look for a good deal from the major solar companies. Again thanks to everyone for their input. This forum and the people have always provided me the best solution to any problems I have run into.

I'm not being a smart A, but always tell people that it takes just as many holes in the roof to mount a 100 watt panel as it does a 160 watt. Of course it depends on the amount of space but you get the idea.    I have never heard anyone say they bought too much. :)
 
I am always impressed by the depth of knowledge available on this site.  And the best part is it's all free for the asking. Good job guys!
 
2004CS said:
... I saw one of the panel sights where you could put in your 12v usage to determine what watt panels you would need.
I think it?s easier than that.  Mostly, solar recharges your batteries.  And you don?t want to draw your battery bank down below 50% of its capacity.  So match expected your solar output (taking into account hours of sunlight, climate, some inefficiency from not having angled panels, etc) to 50% of your battery bank amp-hours.  Your thought of about 200 Watts sounds about right to me.  I have two 115 AH 12V batteries, and both in Seattle and the sunny southwest my 200 watts of panels has fully recharged them each day. But if Kevin disagrees with that, go with what he says.  He has more solar experience and with a larger, more complex setup than I do.

 
No disagreement here. RV solar is a balancing act between consumption, storage capacity and available power. Since all those factors are changeable, RV solar is never, "one size fits all." Other factors that can have a big impact on how well a system will work are, how well a system is installed, and in what part of the country you typically camp. So many variables.

Kev
 
Hi QZ,

QZ said:
Grape solar makes an MPPT controller for $60 that some have said works fine and iirc is blue tooth to your phone for settings and monitoring.

Interesting info. I did some searching and was able to find this: https://www.amazon.com/Grape-Solar-GS-PWM-40BT-Controller-Monitoring/dp/B01FFNNUSK

It mostly corresponds to your description, except that it's PWM instead of MPPT. Could it be the one you were thinking about?

Cheers,
--
  Vall.

 
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