Roll Up/Foldable Solar Panel Set-Up Ideas

[HenryJ]

Still destined for the maiden voyage. I haven't decided what will work best for placement. Leaning against a tire would be my guess.
The latches are both on the top side so it could be hung from them, or the handle on the end.

 

[nebep]

I think the main thing with solar is to create as many ways to attach it as possible so you can "adjust it" with the sun. Don't let yourself get too "attached", (no pun intended), on having to use A,B, or C only - look more at using any of the three with as much creativity as you can so you gain as much flexibility as you can.

@HenryJ -

(I don't know all the solar panel types as well as I should - but, is your panel one that requires being directly in sunlight before it will operate at its peak potential??) - if this is the case, then I would DEFINITELY want as many hanging/mounting options as possible in my toolbox for any situation you might run into - worst part is, experience is what'll give you the best education on the hows....

 

[HenryJ]

... is your panel one that requires being directly in sunlight before it will operate at its peak potential?...

I believe the more direct the light, the better it will perform. That would be the same for any solar cell. Any light and it will deliver some power. This one does not require full sunlight to deliver enough to charge the battery at 14.4V , which is what my regulator delivers.
BP Solar modules

 

[teotwaki]

I'm not doing a lot of expedition style stuff YET - but, for an RV DIY conversion we're working on, I selected the PowerFilm 60W unit he did that post on. It's QUITE a unit!!

It already has grommets on the corners so you can hang it/attach it. They're smaller grommets. A Bungee cord, or, set of 'em would work find to anchor it just about anyway you want.

I'm looking at building up a foldable frame using Http://www.8020.net materials.

I'll probably have the second panel on its way some time this week. The tests with it have been MOST impressive - I've been seeing 17V+ in shady conditions with this panel.

I did order a MPPT charge controller to match with these panels. My basic understanding is that a MPPT controller is "set" so that when the panel is generating more voltage than the battery can handle, it "stores" that and sends it to the battery as it can, so, you get a more efficient panel.

On standard controllers, extra voltage just becomes heat - and, heat = wasted energy, that doesn't make it to the battery.

I'll post more as I know more!!

(From the looks of it, MPPT controllers are a reasonable amount more for the gains in charging efficiency from what I can see - again, will know a LOT more soon!!)

The MPTT controllers do not store energy. That is what the battery does. The MPTT controller is supposed to be more efficient at translating the wattage curve of the solar panel to a useful charging curve for the battery.

This from another forum:

Regarding how MPTT works.

Have a look at the specification sheet for a solar panel.
There will be a graph of voltage vs current.
Power is voltage times current. If you connect the panel to a short circuit, then you get no voltage and hence no power. If you disconnect the panel, you get no current and hence no power. In between those extremes you get power from the panel. The best point is somewhere near the knee on the graph, just before the voltage drops as you increase the current too much. The maximum power point tracker (MPTT) adjusts the load up and down a bit to find out where it gets maximum power from the solar panels.

 

[teotwaki]

What I have so far isn't any more telling than what anyone else has posted so far, but, here goes..

the tester, reading 18.47V in the conditions you see - sun not even hitting it straight on anywhere. Rather shady conditions really..

the tester is hooked up with the panel laying exactly as you see it there, on a balcony, with no sun directly on it. I was pretty impressed by this!

I put some cup hangers on the ceiling so I could hang the panel during early morning straight sun - didn't take any pics of that, BUT, I did get 21V readings when the sun was directly to the panel, and, really, I probably would've gotten higher readings if it were earlier in the day. When I got the 21V readings, it was more mid-morning with sun almost coming straight down over the position of the panel vs. straight AT the panel, so, with sun straight on, I dunno what this would do!! Needless to say, I'm VERY impressed so far.

I did hook up some LEDs.

IN our RV, we have VERY basic electrical needs. LED lights, a MAXXAIR vent fan, and a 110V fridge running off an inverter.

Here's some more info on our conversion:

http://autolox.smugmug.com/Cars/Sprinter-Conversion/8765456_UWbXE#580180270_uP4Mm

It looks as if you are measuring the open circuit voltage of the panel which is not a measure of how much power it can deliver. The panel has to have some sort of load connected. If you put the panel out in sunlight and connected a 100 watt 5 ohm resistor you'd get a better idea of how it is performing. You would need to measure the voltage and the current. If the voltage was 13 volts and the series current was 2.6 amps you's have about 34 watts of power which is reasonable for a quick test

 

[nebep]

Oh yeh - totally agree - just this "checkin' with the voltmeter" thing for me right now is more about seeing that it's performing.

I just got the MPPT controller in the other day - set the panel outside under completely overcast conditions and it was kickin' 17V...

(Again, I know this isn't terribly accurate since it's not part of a system under load - I'm gettin' to that point!! - this thing called life is BUSY!!)

@teotwaki - maybe a bad choice of words on my part - what I mean is that the MPPT controller seems it regulates better without wasting. So, when you have an MPPT vs. standard controller, the MPPT is going to put MORE of the energy from the panel into your battery while the standard will simply let any "over current" go to waste as heat...

(Totally learning solar - wanted to document things that solar newbies have wanted answers to that seem hard to find..and these are things I wanted to know too, but, had a hard time finding answers, so, I just bit the bullet and figured I was gonna set up a small system and see what I could learn, while also gaining another possible means of power...)

 

[teotwaki]

We have all had to ask questions about solar energy so I am just trying to help with the learning curve. I never meant to appear critical of your attempts to learn more about solar. It is very good to get these things out and share them.

 

[nebep]

We have all had to ask questions about solar energy so I am just trying to help with the learning curve. I never meant to appear critical of your attempts to learn more about solar. It is very good to get these things out and share them.

Never took ya as negatively critical!

:victory:

 

[teotwaki]

It was this thread that alerted me to the MPPT controllers which I had not known about. I've been watching for deals as I want one to go with my 54W foldable panel and maximize its efficiency.