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Make a high powered solar panel from broken solar cells

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Step 1: Tools needed

To start making solar panels from broken solar cells you need a few things.
1. 15-25 watt soldering iron
2. Light duty 60/40 electronics rosin core solder (radio shack $5.00 for a roll). You can use a silver solder, but I think its too expensive, and the difference in resistance is minimal. So I just use regular old electronics solder.
3. Multimeter
4. Pencil eraser
5. Solar tabbing pre tinned ribbing (ebay 100 feet is like $20 bucks)
6. A good flat sturdy working surface ( I use a piece of glass, but whatever you have will do)




Why does the tabbing need to go all the way across the top? I mean as opposed to just cleaning the end of the busbar and soldering a small tab to it? Sorry i've never seen a solar cell. Also if a shard of cell doesn't have a dark spot on the back side, is it worthless, no place to solder?
About how much money did this run you? Am I crazy to consider powering a chunk of my home using broken PV's?
johnhearty2 years ago
where can i get those materials?please because we have a project in physics
cheesphht4 years ago
The hardest thing for me to build is the protective encapsulator. Do you build it out of glass or poly? and how was it put together? Or just direct me to the site where instructions to build such an enclosure is available. I want it strong enough to sustain winds but also light enough to put on by telescope's tracking device during the day.
There is a clear silicon two part many home builders use; but it runs around 50.00 a can. It is mixed and poured on the panel while it is face down and a brush is used to spread it.
mattfelice (author)  cheesphht4 years ago
i just made a simple wood frame painted, caulked, with a plexi top
Thank you mattfelice for answers about broken cells and panels. For new guys this is a critical part of making your own panels. Yours is the best statement I have found on the web.... ps/ What's the minimum size (% of a broken/chipped cell) I should use in a panel? Does the size of a broken cell used in a panel matter? If so, what's the rule? Thanks in advance
There really is no minimum size, you just have to remember that a couple of solar cells wired in series is only as strong as their weakest link. So if you wired a piece that was producing 200 milliamps in series with some that produce 1.5 amps it's only going to produce 200 milliamps. So if you use small ones, make sure they're only in series with other small ones.
fat642 years ago
I just ordered some broken pieces to sweden for a first hands on experiment. Taking the time to document this is what generates real wealth, thanks for sharing matt. 35 Watts sounds impressive for that, where in the world do you live btw? :)
Hello,...can I charge a bank of say six battries with this?.and if so how long in good sun?..I'm old and new to all this solar bussiness,and really hoping this old dog can learn a few new things,Thanks John
lampajoo4 years ago
Could I use regular copper wire instead of the ribbon?
mattfelice (author)  lampajoo3 years ago
Sure. Copper wire should work fine
conora2b4 years ago
Hi Matt
this is a really great guide but im kind off stuck on my own project

I am running a 24V battery bank for my wind turbine and want to add solar to the same bank so far i have bought 110 3"x6" solar cells rated as follows,
0.5v x 3.5a = 1.75w each

this is what im thinking off so far please correct me if im wrong in any part of it
to get 24V i need 48 cells in series and 2 sets in parallel (94 cells in total 24V + 7a) to make the most of my cells im thinking of building a 26.5V panel (104 cells in total 26.5V+7a)

is this the right way to go about it or should i lower the volts and increase the amps going to my battery bank and if so will it still store a a 24 v charge?
blacmis4 years ago
There is a VERY informative book "build your own solar panel" by Phillip Hurley that would answer every question on this thread and more. If you really want to build a solar panel and make it easy and be confident doing it. Check the book out.
Wow, that looks kind of hard, and looks like you have to be concentrating a lot not to mess up. Nice job!
mattfelice (author)  GorillazMiko6 years ago
Yeah, what makes it hard is how thin and fragile the cells are. The first batch I got, I couldn't believe how thin they were.
hey, so the top of the cells are negative and the bottom is positive? ive seen a few being constructed and the engineer always just soldered the top two ribbons and nothing underneath. am i seeing things right? also great project, im trying to do the same but i can't believe how thin theses are. im trying to connect about 40 of theses in series but its hard to know what the best steps are to make them into one huge panel. aslo which is the best way to arrange them, parrallel or in series? thanks, Mike
How Many Volts do you need?, amps? Series gives you more volts and parallel gives you more amps. You can combine the two to make it more suited to your needs: If each panel, +{lllll]-, produces 1v and 1amp then this panel produces 5v and 4amps
solarpanel.jpg
ahh ok thanks for the reply. now i get it.
Angus065 years ago
Yeah going along with what blindsided said, how is it that you wired those all in series and managed a whopping 1.85A out of that?
mattfelice (author)  Angus064 years ago
to gain the amperage you want just wire a few in parallel to make a "single cell, then continue the series. You can see examples of this on my panel
bomberss275 years ago
What are the dimensions of the entire solar panel? Also, how do you attach this to a charge controller or alligator clips which I could use to attach to a battery?
mattfelice (author)  bomberss274 years ago
its about 4' long by 15" wide
Jalloy4 years ago
(removed by author or community request)
mattfelice (author)  Jalloy4 years ago
please do
I am looking at running a 1,000 watt heater. How many watts will this operate?
A kilowatt solar array would require (approximately) 100 square feet of solid collectors. It would only deliver its kilowatt when the unimpeded sun was shining directly straight on to the array. I'm guessing the pictured array delivers 10-15 Watts.
mattfelice (author)  geetz4 years ago
19v 1.85 amps 35 watts in partial sun
jerber265 years ago
hi, can you connect those broken pieces together so that it will look like one whole solar panel?
mattfelice (author)  jerber264 years ago
you could but it would be realy hard
I am new to this stuff. so I'm not being sceptical, but I am wondering how you use this if one does not have an inverter.
I think many of the 15.4 inch notebooks use 19 or 20 V charger. So it could be probably used to charge/power one of those. I would recommend some voltage stabilisation.
Yes, this is the voltage that a 15.4 inch notebook would use normally, but you have to remember the current on the chargers as well. Most of them are in the excess of over 65watts. This solar panel would only be able to produce around a 10 to 12 watt max power. So yes it could probably charge a laptop but after a day or so of direct sunlight. It could never power a laptop unless it is big enough for a 65 watt which would be a very big solar panel.
mattfelice (author)  johnsocm4 years ago
is a full 35 watts, not 10 to 12
If you use it to charge a battery or other DC powered device, no inverter is necessary.
Here is a place to get solar cells if not free, then real cheap!!! As you travel down the road you will see solar powered highway warning signs used by various road and utility departments. These signs are subject to a lot of abuse...especially drunk drivers...and the solar panels get damaged. What happens to these solar panels??? The insurance company pays for the repairs and the broken panels go IN THE TRASH!!! These signs have phone numbers and contact information on them so WHEN IT IS SAFE TO DO SO...stop and jot these numbers down. Also look in the phone book for places that rent these signs for special events and ASK if there are any broken panels, and that you are doing a science project. If it is for educational purposes, many businesses will gladly give you damaged, seconds or old stock items in order to help young budding scientists. I have been given windows, glass patio doors, corrugated drain pipe...even a piano all in the name of science!
alxjpow5 years ago
Cool, we broke one at work.. so I might get a solar panel for free! (after doing this though of course) ;) Thanks~!
Brumario5 years ago
Hi. how many watts this solar panel produce? How many solar cells do I need to produce 60 watts or 100?
I have built a few of these - one problem can be the solder refusing to wet and the solution is to dip the solder in some solder flux (zinc chloride) then put the drop at the end of the solder on the busbar, wait 10 seconds and then solder. Broken solar cells are much cheaper than whole ones and work just as well! Nice Instructable :)
Do you have any good sites where I can buy chipped/cracked solar cells??? Any where but EBAY ????
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