Tagged: DIY solar panels

Jul 17

DIY Solar Panel Tutorial

How To Make Solar Panels (courtesy of GreenPowerScience)

Hello there! I’m your host, Dan Rojas.

And I’m Denise Rojas. And, today, we’re gonna make our own solar panels! This is the famous Harbor Freight Solar Panels that were used in many of our previous videos. Today, we’re gonna be using cells of a different type!

There are 3 basic types of cells used in most solar panels. The least efficient and least expensive of these cells is the Amorphous cell. Now, this what the Harbor Freight system is. The cells are deposited on glass, usually, and there are kits that come with this, they’re really tricky to work with. I pretty much don’t advise you to try to make these. The nice thing about these, because they are deposited on glass, even though they are less efficient than the other type of cells, is the fact that you can just dunk these in water. You can just pretty much do anything with them. They’re really, really durable.

There’s also Monocrystalline. Those are hexagon cells, Those are the most efficient, and the most expensive.

The cell that we’re gonna be working with today is Polycrystalline. These cells are almost a watt and a half, almost 2 watts a piece, and you can get these in lots of 100, and you can get them in just about any size. These cells, you have to tab them together. Now, one thing about these cells is they’re very fragile. And, um, you can see that it didn’t take much at all to break that. You’ve gotta be really careful when you work with these, because that was about a $2.00 break that I just did right there.

Now, one thing about these cells is, they are, like I said, about a watt and a half to 2 watts a piece, but they’re .5 volts. So, in order to get your voltage up, to say, 18 volts to 20 volts, you need to chain together 36 of these, or 40 of these, depending on what voltage you’re looking for. So, what we’re gonna be doing is tabbing these cells together today.

There’s basically 3 different things that you need for this. You need:

Tabbing wire, which is a thin wire that’s got a deposited metal on it. This actually solders to the cells.

There’s also a bus wire, which is basically the same thing as tabbing wire, but it’s a lot thicker, so it handles more amperage, and you use this to tie your strings of cells together.

There is also some silver solder, which is basically, you use to enhance the soldering joints.

You also are gonna need a soldering iron. They usually recommend that you use a 65-watt iron. We’re gonna use one a little bit less than that.

We’re gonna show you the basics for this, and, in future videos, we’re gonna show you how to add a lot of components to the solar panels.

So, we’re gonna get started! I’m gonna plug the soldering iron in. On thing that Dan forgot to mention is that he’s gonna be using this flux pen. Now, this pen, it actually smells like rubbing alcohol and, what it does is it opens up the cells, so that way it can accept a better soldering joint.

When you get your cells, they usually come in a bundle, like this. And, as I said, they are extremely fragile – this is another one that I broke! So, you want to be very careful with these, and handle them with care. I’m gonna show you a close-up of these, and explain exactly what’s going on with them.

What you’re gonna notice with these cells, is that there’s a series of small white lines, and 2 big lines. This is where you tabbing wire goes. Now, on the back side, there’s also 6 little joints where you solder the tabbing wire to. Most solar cells like this are usually negative on the front, positive on the back. So, in theory, you could take a bunch of them and stack them like batteries to build up the voltage. The problem is, only one cell would get the sunlight, so you can’t do that.

So, what you end up doing, is you end up taking tabbing wire, and you run it down the length of this, and you leave some extra. And, the next one attaches to the back of the next cell, and you go from there. So, you end up tabbing them together like this in long chains.

We’re gonna lay it flat, like that, and the you take your flux pen and you basically just go right up and down it. Now, it’s a good idea not to drink a lot of coffee on the day you do this, like I did, because, the steadier your hands are, the better off you are! You want to have your tab wires to be twice the length of the cell. Now, I went ahead and cut these in advance. You basically just measure it and double it over. It’s a good idea to do all of your tabbing wires in advance. That way, you don’t have to come back and do this step. Also, be careful with your soldering iron. I just grabbed it in the wrong spot and burned my fingers, so I’m gonna have 2 nice blisters, but, you basically try to get it started so you know where you’re gonna end. And, you hold it down, and the tin that’s on the outside of this should adhere to this. And, you can see that that locked down. Now, you’re gonna hold it the length, just like I have it. You take your soldering iron and you hold it flat like this, and you just gradually work it down the length of the cell.

Now that you have 2 of these tabs, you’re gonna take them and flip them over, and you’re gonna attach them like this. You’re gonna want to get this tabbing wire nice and flat – get it nice and straight. And, you’re gonna arrange them like this. Now, it’s a good idea to have a setup of exactly what you’re doing. Some people will build a little form, so that these are in a perfect, straight line and they don’t look like crap whenever you’re done. But, what you do is you bend the wire up, and you take your flex pen and you want to put it on every single one, like that.

Now, this is an area where the solder actually comes in, and you can actually use it for this. Basically, get yourself a little bead of solder on there, and what you’re gonna do is, get your tabbing wire positioned. I’m gonna use a little clamp to hold it down, because this wire does build up some heat. Let me get the first one in place here. We now have 2 cells that are joined together! So, we’re gonna go outside and we’re gonna see if this produces one volt real quick, because you want to test these as you go along. The time to replace a bad cell is now, versus once you’re completely done with your project.

Now, the way that you want to test these, is, you attach your negative lead to the front, which is this tabbing wire here, and then, you can touch pretty much anywhere on the back. Alright, so you basically take it and, we’re gonna test it and touch this to the back of this here. And you can see that we’re getting one volt out of this, which is, these 2 together produce the one volt. And, if I cover them up, they drop. So, these 2 panels – these 2 cells, are actually good to go.

So, what you’re gonna have to do in order to get a…something to charge 12 volt batteries – like these over here – what you’re gonna have to do is you’re gonna have to do this 36 times, total. So, you’re gonna need 36 of them to get to the 18 volts that you need.

So, this is what we did just now, I got a couple of blisters in the process! And, you can see that it’s a pretty tedious process to do, and, doing is this way comes out to be about $2.00 a watt, maybe a little bit less than that. As you can see, these are very fragile and they break easily, so you have to encase them really good. So, you need to put a glass cover over them. You need to seal this so moisture doesn’t get in there. There’s really a lot to the DIY process with this.

To encase it, does somebody improv on that, or, is there a professional case to use?

We’re gonna be doing that in future videos. We’re gonna be actually trying different ideas in order to…you basically make a frame, encase it in glass and seal it, so that moisture doesn’t get in there. Some people will seal these in resins or waxes, and that’s a good way, too. You just…it is a pretty tricky process! I personally don’t really see…I don’t really necessarily have the patience to do an entire panel…we’re gonna do it for our video.

Well, it seems a little hard to get the soldering and the strips on it just right, but, within time, it would come a lot easier. It’s definitely a practice thing. And, our soldering iron, by the way, is not a good soldering iron for this! You want to get – you wanna buy a good one that gets a really good heat buildup to it, and it will be a lot easier.

It looks great, and, so, somebody would have to get this…how many times would they have to produce this?

To charge a 12 volt battery, you would need to put 36 of them to get to 18 volts, or, if you wanted 20 volts, you would need to do 40 of these.

So, does it go in a row, or,how does that work?

What people usually do, is they’ll do 18 of these, and then 18 of these, and then tie those together, so that jumps the voltage up. And then, the bigger panels, if you want to increase the…’cause 36 of these would produce about 60 watts, 65 watts. The Harbor Freight system that we have outside is 45 watts, so if you put 36 of these together – make sure I’m doing the math – yea, if you put 36 of these together, you would have a more powerful system than the Harbor Freight out there. It would cost you probably about 100 bucks to do that with these cells, the tabbing wire. You have to take in to account that you’re gonna break some along the way. And, then you have to add the case cost to it, because sealing these…the Harbor Freight system has been out in the sun, it’s been out in the rain, it’s been dipped in water (some of the smaller panels), and they work fine. This is gonna be up to you, how well that works out.

Can it be embedded in acrylic, or is that too…

You can encase this in resin – you can definitely do that – different types of resin. You just want to make sure that the contacts all stay good together. And, it’s really important to test these as you go along in case they don’t work. You also need to add some blocking diodes to this, because you don’t want it to drain your battery. You need to make sure the voltage only goes in one direction.

This process is good for somebody who’s on a budget, who has a lot of time on their hands, and who is very patient and wants to do it yourself. If you’re not that type of person, buying a pre-manufactured system is probably gonna cost you double, or a little bit more than that, but that’s your call with it.

Well, I definitely think it’s worth completing, as many as we have, and embedding it into something, for a future video. We spent about $400 on a 150-cells, a little bit more than that, and that’s the equivalent of about 300 watts. So, if we can get one together, a 300-watt solar panel is – well, we wouldn’t do one, but, 300 watts of solar panels is pretty expensive to buy.
I think the challenge is worth the effort on it. You do get better at this, by the way. This was like the 3rd one that I did, and again, the soldering iron – crappy!

If you go to our website, we will have information on where you can buy all this stuff. There’s different people that sell it on eBay and that sort of thing. We’ll have some links to that, and you can at least buy some cells, buy some of this stuff, and see if it’s for you!

I’m your host, Dan Rojas…

and I’m Denise Rojas!

Thank you for watching, and enjoy our videos! Oh, and don’t grab the soldering iron in the wrong place – that really hurt!