Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Broken glass solar panel (mistake)?
Hi all, 

I may have made a slightly knee jerk/silly decision today. I've bought 16 320W solar panels from a gumtree seller, all with broken glass. £25 a pop. I actually haggled and got them for £350, but that's besides the point. Have I made a mistake????

My rationale is, I have no solar panels at the moment to speak of, and I've got theoretical 5.1kW of panels for the price of 1 new perfect one? I know i'll more than likely get no where near 5kW but I thought it was worth a bash at fixing them up. Resin or varnish maybe?? Has anyone got any suggestions?

Worth noting I picked the panels with good 38V on the meter when in the sunshine and left the others.


I wouldn't call it a mistake, more like a great find! Smile

The glass is relatively easy to repair. You can't really replace the glass as the cells are epoxy'd to the glass. However, you could add in a clear filler that will connect all the shards back together and minimize the chance of one falling out.
Now, if you "can" get the glass to come out, then you might be able to replace the glass. If you can, then I'd suggest looking around for sliding glass doors, large windows, etc that might be being sold at garage sales, craigslist (or whatever your counties version of it is), recycle centers, reclaim centers (we have one called the Repurpose Project; ppl generally just give them left over scrap, or removals from remodels and they sell for dirt cheap; these are actually a not for profit in our local city)

You can at least start your projects with those. And now, every other panel you buy at full price has been slashed lower due to these being so cheap. So the overall costs will be far lower.
And smart move for hand picking the voltages.
Proceed with caution. Knowledge is Power! Literally! Cool 
Knowledge is Power; Absolute Knowledge is Absolutely Shocking!
Certified 18650 Cell Reclamation Technician

Please come join in general chit-chat and randomness at Discord Chat (channels: general, 3d-printing, linux&coding, 18650, humor, ...)
(this chat is not directly affiliated with SecondLifeStorage; VALID email req'd)
I can't see why that would be a mistake either. Seems more like a good deal to me. The glass can be fixed, Youtube has an extensive amount of HowTo videos abot that, I'm sure!
Nice little score.
Can I assume that by broken, you mean the glass is cracked but none of the glass is missing?
If that is the case and you are only concerned about water ingress, then perhaps you could use some self-adhesive clear film?
Kinda like the stuff school kids wrap their books in.
Pretty sure you can get this stuff in various widths and from memory 3M/Avery/Arlon make UV stable vinyl films.
The film may lose you a few watts, but for the price... meh

Just a thought.

EDIT: Or clear window film... here's a random youtube vid showing application:
I wouldn't have paid $512 for broken panels. That's a lot of money for something that's broken. I would have offered $100 with a "take it or leave it" attitude to see if he came down any.
This guy made a fairly clear video about the process.

Exterior varnish works well and isn't too expensive. Best applied with a gloss roller (not a fluffy roller) but will take over a week to dry fully. I went for just one coat, but may try 2 thinner coats next time. I've not managed to find an exterior varnish which is completely clear, they seem to have a yellowy tint to the finish.

Cleaning them thoroughly before applying the varnish is a must. The cleaner the better, then hoover off any loose bits, then varnish. Doing this outside may attract a lot of bugs which could get stuck into the varnish.

While the initial cost of the panels is low, once you factor in the cost of varnish and the time to apply it, then factor in the life-span of the panels (I'm guessing 5 years or so compared to 25+ for unbroken ones) the saving is still there, but less significant.

I went for cracked panels because of cost, my entire solar budget is less than the cost of just new panels.

Try it and see. at that price it's a gamble worth taking!

I used this varnish by the way.
Wattsup likes this post
To expensive if you ask me... but all have different prices on their free time Smile
The Ultimate DIY Solar and build place
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 100kWh LiFePo4 | 20kWh 14s 18650 |  66*260W Poly | ABB S3 and S5 Trip breakers
Upcoming: 14S 18650~30kWh
Besides water getting into the panels, another concern is structure strength (how big are the cracks?) and the actual solar cells are very weak and break easy like super thin glass. Some sort of epoxy might be ideal for the strength. If you live in an area with snowy winters this is a more major concern, if not rain water probably isn't such a big deal. Water in the crack is if it freezes though.
100kwh-hunter likes this post
Did you ever get any of these panels setup? I've just finished connecting up 2 300W panels with cracked glass. I'm in essex in the UK and the sun has not really been out this week at all. I have been getting at most 1.5A from the panels in series at the charge controller. I used an exterior clear varnish to seal the cracks. Seemed to work pretty well.
I'm no expert on solar, but I'd suggest testing each panel separately and make sure they put out close to spec (within 80% should be a fair target). Wired in series will limit you to the panel with the lowest amp output if I'm thinking right Parallel would probably be better since I think the voltage would either average out, or the lowest voltage would be your output, but long distances with low voltage isn't fun or cost effective.

Forum Jump:

Users browsing this thread: 1 Guest(s)