Solar panel resurrection

[GILow]

Hi Cruisers,

We had some pretty crazy weather a while back, during which something BIG and very airborne (at least 12 feet in the air) crashed into one of my el-cheapo no name brand solar panels and shattered the glass. The glass has done the classic pebble style shatter of windscreen glass but oddly enough it has remained very firmly attached to the panel itself.

Now, these panels are a temporary setup, my plan is to replace them with something of a decent quality in four years when we cast of the lines, but in the interim I am sort of missing the 140 watts that particular panel provided. I removed the panel immediately after the storm to stop it corroding and it has occurred to me that maybe I could coat it with something to keep it mostly waterproof without losing too much of the output. The best idea I have come up with so far would be some clear contact film but I wonder if anyone has some other suggestions? Some kind of paint on clear lacquer perhaps? Resin?

Matt


Sent from my iPhone so apologies for weird autocorrect typos.

[Sea Dreaming]

Clear contact film was my first thought too. Or maybe a layer of plastic....
Like this
http://www.amazon.com/FloraCraft-Flo.../dp/B003V4A8E0


There is other stuff on the market but I post the link to the floral stuff because my poor brain can't recall the name of the alternative. But it might give you a place to start.

[Nicholson58]

You might use two-part clear silicone rubber casting resin from US Composites. (soft & flexible) Also, they sell crystal clear epoxy casting resin. (Somewhat brittle) You will likely lose watts due to screening by the coating material. Perhaps its time to get a new 18 - 20 % efficient panel?

[GILow]

I am resigned to losing efficiency doing this, but I would rather buy new panels immediately before we weigh anchor. Anything that can keep the poor shattered thing going passably well till then will be good.

Maybe the contact sheet from Amazon with pretty flowers will make it look like I have window box garden at the back of the boat.


Sent from my iPhone so apologies for weird autocorrect typos.

[Sea Dreaming]

The amazon link is for clear casting resin

[GILow]

Oh dear. I feel silly. Thank you, that looks like a very good option!


Sent from my iPhone so apologies for weird autocorrect typos.

[GILow]

Just to report back on this for anyone searching. I went with clear casting resin as suggested and it has worked well now for a couple of months. The panel has lost about 10% total output from a very crude set of measurements using ammeter and voltmeter, but that may well have already been the case from the original damage. So as a method of squeezing a bit more life out of what might otherwise been a throwaway panel I can recommend this option.


Matt

[GILow]

One final update. The panel is dead. RIP el-cheapo panel. I've just set offf for a few days aboard and noticed my solar output is crap. A quick check unplugging each panel revealed the shattered panel is putting out no power at all. This has happened some time in the last month. So, as a way of prolonging the panel life I suppose I have to say it was probably not worth it. Bit of a bugger too, we have days of sunny skies and light winds forecast. So I'll get bugger all from the wind gen and only half my expected power from the panels. Sigh.

[44'cruisingcat]

You got more than a year out of the repair!

[GILow]

I suppose so. But it was a few $ of casting resin that was probably spent better elsewhere in retrospect. :^(

[masonc]

An el-expensivo would probably have cracked also. All panels use toughened glass which does not like impacts with hard objects.

[GILow]

Yeah, I am taking some solace from that thought.

[Jim Cate]

Just curious, Matt... what was the relative cost of your repair vs the cost of another el-cheapo panel?

And, don't forget the benefit of the good feeling you got when the repair worked for a while!

Jim

PS good luck in the new job...

[GILow]

I think the casting resin was around AU$25. That was the only cost for the repair. But there was a bit of labour pulling the panel off the boat and putting it back again. I suppose that would have applied equally to a new panel too. The panel itself cost around AU$160 from memory.

The good feeling was somewhat undermined by not KNOWING if I made any real difference. The panel worked before I put the resin on and may well have worked just as long without it. I just don't know.

So, on balance, I probably would not do the same thing again. If the panel had lasted through till the planned replacement date three years from now I would have been more confident in the value of the fix.

[masonc]

If you are using a 12V panel with a PWM charge controller, no issue. But modern day solar installations use up to 150V max Voc on the PV side and MPPT charge controller. In this case, a cracked panel can expose sailors to hazardous voltage. While it's fun to try fix a damaged panel, it's rarely worth it on a modern solar array. Change it and move on.