Anyone have experience with unisolar flexible pv

[ddruker]

Hey that's why we love this forum - I get so many great ideas here.

Cross your fingers for a Stanford victory over USC this weekend, and my Airstream (and it's unisolar panels) will be boondocking at the Rose Bowl over New Years...

[Keyair]

UCLA household here, so we support anyone for a win over USC... Lol!
Great info everyone!

[Keyair]

Question:
Was scanning Ebay and found these...
http://www.ebay.com/itm/Uni-Solar-L-...YAAOSw8aNXGnXw

My question is how would you encapsulate them once you have tabbed and soldered the panel together?

[BigAl]

keyair,
That seems like a lot of work to me. Why not use the 136 watt panels available on ebay from soldonweb. I installed 4 68 watt panels in series for about 65 volt output. That way I was able to use thinner wire.
They have worked great since I installed them.
Al

[Keyair]

Thanks for the input Al.
I agree its a lot of work, but I need to custom build panels to suit the areas I have available...

[Troutboy]

Seems really expensive as well. Have you looked at some of the custom sizes from Amsolar, and I think either zamp or go power have smaller panels and flex panels.

I have read that the flex panels are not that reliable.....


Thx
Troutboy

[Keyair]

Expensive?
I read the description states 7.3w/1.6v per cell, x 100, so that is 730w/160v for $200..
Most 100w panels are about $200 a pop, so I thought it was good value. Yes, I have to tab, encapsulate and wire, but I doubt I would be much more than $100/$150 total..
As stated, I have a very specific agenda for areas that I want to cover with solar, and they are curved. I dont want big, ugly aluminum framed slabs stuck on my rig!

[Troutboy]

Cool, I think I did math wrong. I thought it was three times the cost of a normal panel. Would love to see the finished work. Good luck


Thx
Troutboy

[Wabbiteer]

Those still need a supporting/cushioning backing and a trick little Z-fold in the tabbing then perfect EVA/Tedlar encapsulation, and some mar-guard glazed surface to protect the EVA, then have everything expand and contract with temperature change exactly the same... Run don't walk away from that project, want me to say it twice in CAPS?

https://www.amazon.com/dp/B01M4MXRDD <---43" x 12" 50w flex pv
https://www.amazon.com/dp/B01NBHT9NI <--- $150 100w flex pv

Best rigid panel --> 40.8 x 20.7 100w Eclipse (teeny!) https://www.amazon.com/dp/B01B3TEM1E

Maybe look for bulk deal on 30, 40, 50w flex panels - vendors on ebay & amazon both will usually offer discounts if you write explaining what you need...
They are getting better at pricing on the semi-flexible panels and are getting different size/configurations to market.

[Tazameir]

Like alot of you have posted about, I as well have a set of 136w panels I plan on installing once it warms up. The only thing I'm debating about though is do I shine up the roof before I install them, or just clean it. I plan on shining up my entire Airstream like a mirror ideally at some point this year. It's an older one that is pretty dull at the moment.

Can't wait for it to warm up!

C.

[Keyair]

Thanks for the input Wabbiteer!
Now I am rethinking my plan!

So, I am unable to find the 68W panels anywhere, but the 136W and 128W units are still out there.

Let me get this right..
DDruker..
You just cut right thru the panel, at a cell junction wherever it made sense dimensionally, and soldered, and ran cable between the original join points?
This made the panel physically fragmented, but electrically unchanged?

[ddruker]

yes that is essentially correct.

You also need to do a bit of careful trimming of the cut ends to expose sufficient copper conductor to solder to.

I wasn't happy with the process i used to mechanically seal the cut ends - I have it on my list to go redo that part of the procedure - perhaps using caulking or mastic this time. I tried to bond a rubber membrane to seal the cut ends and it has peeled away over the last couple of years.

[Keyair]

Could you use an EVA film or something?

[1derer]

Has anybody shortened a e-pvl 144 and used the part that has the connection box on it so that they then had to so something to the other end of that part? I'm assuming the two wires that run along one edge have to be connected to the two wires that run along the other edge.
I hate to tear apart the end as it comes from the manufacturer just to see what's going on in there.

[BigAl]

Originally Posted by 1derer

Has anybody shortened a e-pvl 144 and used the part that has the connection box on it so that they then had to so something to the other end of that part? I'm assuming the two wires that run along one edge have to be connected to the two wires that run along the other edge.
I hate to tear apart the end as it comes from the manufacturer just to see what's going on in there.

Do a search for member "Drucker" . I think that's it. He posted a whole thread on doing just that.
Al

[1derer]

I did the search for Drucker but this is the only thread that he shows what he did with Unisolar panels. He didn't do anything with terminating a run other than using the end that came with it. He does speculate in one post that the end is wired in parallel.

As he says, the tough part is taking that first step of damaging the panel you just bought. I'd like to know how to make an end cell out of a cell that wasn't the end cell before I tear it apart.

One thing I don't understand even after looking at the pix he posted is: In post 23, he shows a pic of a bypass, but then in post 29 where he shows how he wired two cells together, there's no bypass shown. Do you just discard it or what?

Also, if #10 wire is what he advises to connect cells together, why does he use #7 wire for pigtails. If I was an electrician, maybe I'd know. But I don't know if he's an electrician, so I don't know if what he did is optimal. But I'm real glad he did what he did. Otherwise, I would not have put these panels on my bus. But as you can see from the pic, I'm going to have to chop up a couple panels to complete the runs I've started.
At least the pic shows they can go places besides a flat roof. When I complete the runs and get a charge controller, I'll find out if doing what I've done so far has destroyed the panels or not.

[ddruker]

I'll try to answer all of you questions.

1) Did I terminate the cut panels?
Since I was just separating the panel into multiple sections, I didn't try to figure out how the end section works - I just split the panel up, and then reconnected the cut sections. I do know something is going on in the final end section to complete the circuit, because the panels do not generate power until it was reconnected.

2) Why did I use X gauge wire for wiring the panel sections?
Because I had it laying around. As long as you use wire that is similar to the gauge of the conductors in the panels, you should be fine. It's always better to err on the side of thicker conductors, so you avoid voltage drop.

3) Why did I use Y gauge wire for connecting the panels to the trailer?
To reduce voltage drop. As I recall the run was about 25 feet. The thicker the conductor, the lower the resistance of the cabling, so the lower the voltage drop going to the trailer. Avoiding power loss due to cabling was also why I wired the panels in series (to get higher voltage) rather than in parallel.

4) Did I get rid of the bypass?
Nope - I simply split the panel into pieces and reconnected the cut sections - really I just extended the traces that are inside the panels using external wiring.

5) How risky is this?
Test your setup on the ground before you adhere it to the top your trailer! The risk isn't so much in destroying a $200 panel, it's that it would be a ton of work if your got it on the trailer and glued in place and it didn't work.

I can report that my panels are still working well. Just back from 5 days at Yosemite...

[BigAl]

Hi Dan,
Lucky you to be able to camp near home at this time of year. Just went for a dive with friends today in 37 degree water. Too cold for camping at 7 degrees F.
Can you tell me if the cells in a panel are in series or parallel? I used the panels the way they were and hooked my four 68 watt panels in series. Get about 70 volts 4 amps. Used 11 guage wire .
Al
PS: Happy new year.

[1derer]

Thanks for answering my barrage of questions, Dan. Since Big Al's got another one, I'm venturing to ask another one too so you can do us both in one shot:
If you retained the bypass, how come I don't see it in any of the pix where you showed how you connected the sections together.

Here's one for whoever can answer it: I would imagine what's going on in the end section is that the equivalent of Dan's red wire from one long edge connects to the red wire of the other long edge, same for the black wires. What else could be going on in there unless they just dead end?

And I also wonder what's going on in the end that has the factory supplied external connectors coming out of it. There are two, so maybe the equivalent of Dan's red wire is one of them, the black wire the other. If you knew the how to, it seems you could cut these panels up to make a panel any length you wanted. It could be just one section that puts out only 6 or 7 watts, or maybe it could be any number of sections long?

If one knew what's going on at the end with the factory supplied external connectors, I would think you could have them come out the back, for instance, to minimize the likelihood of your local prankster yanking the connectors off (probably not a big issue when they're all on top and out of sight). It would also look better with no protrusions (Again not important if everything's on top) You could even put the plugs on the ends of the external connectors after they'd gone thru your roof both thru one small hole instead of the one or two big holes you have to make to accommodate them as shipped.

I'm planning on extending the runs so I'll end up with a total of four runs each just a little shorter than the length of the bus. About 900 watts worth if the sun was shining full blast from all directions. As it is, maybe I'll get half of that at any one time, but at least it piles up in the batteries.

I tried asking a few such questions of an outfit in Tucson that also makes flexible panels (www.globalsolar.com) but they don't care to talk about anything unless you're buying their stuff. Oh well . . .

[1derer]

I just discovered the website I cited doesn't show up from the link in my previous post (#79) & I don't see a way to edit a post I already posted. But here's a link that actually gets you there:
http://www.globalsolar.com/global-so...ch-new-website