100W Solar panel || DIY or Buy

In this episode of DIY or Buy I will show you how I created a 100W solar panel by myself. Along the way you will learn how to wire up solar cells and how they are usually wired up in a commercial solar panel. At the end we will then evaluate whether the DIY version is cheaper to produce.

Thanks to JLCPCB for sponsoring this video

Music:
2011 Lookalike by Bartlebeats
Killing Time, Kevin MacLeod

[rs]

“I happened to have some solar cells just lying around.” Guess that saved you a few steps.

[vincentrobinette]

One more thing you could have done with your version: Put a reverse bypass diode on each cell, so if a cell becomes shaded, you only lose that 1 cell, plus the forward voltage drop if the bypass diode. I would recommend low voltage Schottky diodes, because of their lower voltage drop. With only 2 diodes, if one cell is shaded, you lose two entire columns of cells, which is half the panel! The fact that you made your own, you could put those diodes in parallel with each cell, producing a better panel for less than ideal conditions, than the commercial panel. I would have used tempered glass, rather than acrylic, for the glazing.(that's what the commercial panel uses)
One other recommendation: Mount the solar panels on stand offs, so there is a gap between the backs of the panels and the roof. As the cells get hotter, the output voltage goes down. Semiconductors are negative temperature coefficient, so their voltage drops as temperature goes up. The cooler you can run the panels, the more voltage they will produce, with no reduction in amperage. That will allow them to produce more wattage.

[TheZwevegemsb]

thanks for the advice, I was almost planning to make my own solar panel roof..

[ElectronPower]

Nice video! Here are a few more tips: did the resin leave any gaps between plexiglass and the cells? If yes, you could try pouring a thin layer of resin onto plexiglass and then place the cells on top of it, to avoid any air gaps. The problem with air gaps is that when the temperature changes, water can condense on the surface of plexiglass and reduce the output and in the end even mold can develope in those spaces which is really pain in the ass (it permanently affects the output). Also, you can clean the flux and fingerprints with acetone in a spray bottle, thus further improving the output. And one more thing: plexiglass will degrade under UV light over time and decrease the output. It's also not very scratch resistant which can be a problem when cleaning the panel. (use glass or tempered glass instead)

[themanthelegend]

You should look up aluminum brazing/welding rods. You can aluminum weld with a hand torch.

[napoleon_bonaparte]

I have DIY'd this too. I did not use resin, and I instead lay the cells out on painted plywood, and sealed the outside edge of the plexiglass over the top with strong adhesive, and topped it off with a C-frame. Takes 8 hours to solder indeed, it's actually meditative. My tips:

- Use a thick frame like Great Scott did, thinner ones are not sturdy enough and the space behind the panel is handy for concealing wires, drilling holes and mounting.
- If you're not using resin, make sure to keep any live wires away from the frame.
- It's much much easier if you don't have to cut the plexiglass to size, it can be brittle and difficult to work with.
- Sealing the cells from the elements is crucial and probably worth spending good money on resin to achieve it.

It might be a good idea to use a backboard and a C frame, then fill the inside of the frame with epoxy as a seal. That way you use far less resin and mirror adhesive. Haven't tested this idea though, just a thought.

[TheIceLeopard]

Even though BUY won, I STILL LOVED THIS VIDEO! I love solar cells and panels.
Suggestion for next video: How about DIY Solar cell, aka homemade?

[Petex]

Regular plexi glass will turn yellow-brownish in a year. Even "UV-resistant" plexi will suffer this in some degree. I think that the glass would be the best way to go

[SeaScoutDan]

For DIY, people often forget to factor in their time. If it takes 10 hours to save $100, you are working for yourself at $10 hour.

[DigitalYojimbo]

Isn't the plexiglass going to get cloudy because of uv ?

[aatkarelse]

The only bastard crasy enough to still do a full diy panel even tough you know it will compare poor against commercial panel, i call that dedication !

[ivangutowski]

By far the largest improvement you can make, which has worked very well for me.

Obtain old double glazing units, people have them in skips all the time or online when conservatories are being replaced. This provides tough, cut to size glass with aluminium surrounds that can be cut off using a Stanley knife and replaced with sealant. This will result in a cheaper and far more durable system.

[KD-mxqt]

In my physics class, my group managed to increase the light intensity and efficiency significantly by adding aluminium foil as a funnel into the solar panel, it got quite hot quickly but aside from that, I have no idea why this isn't done commercially. Does anyone know?

[PS_on_youtube]

Very nicely done!

I considered doing a diy panel in the past, but (as you discovered) the costs of a diy panel are definitely more.

...plus you wouldn't want to use plexiglass, they make a special type of 'glass' for solar panels.

[LoganJarrell]

I'd be insanely curious to see you revisit this one. I suspect that there may be a way to either source cheaper materials, or save some bucks by buying more cells, or maybe getting different, higher (or maybe even lower) efficiency cells. I wonder about encapsulation with resin vs vacuum sealed plastic sheeting. I wonder about acrylic vs glass (and then tempered vs regular).

I even wonder about what the absolute Frankenstein solar panel would look like or do. I'm talking "what do I have laying around the shop?" copper wires from old chargers instead of nickel strips, glass salvaged from some old monitor or something. Frame made out of literally anything. All in the name of curiosity/science haha.

[capistor]

this episode was finally something close to the level of a beginner like me. love when you simplify it like this/ choose easy project. We need more!

[simonstergaard]

Normal plexiglas have UV blocker added, which might lower your yield.
You can buy plexiglass without UV blocker, but you will have to make some calls...

[tornadokat]

I just ran across a set of these cells on AliExpress earlier today and the cheap price caught my eye plus I wondered how you hook them all up. Then I found your video tonight. Now I see how you connect them together and the work plus other costs to consider. Thanks a lot!

[niel]

Why do you mount your solar panels directly to you roof?? I think it need some airflow under the panels for cooling

[readyanarchy]

If you’re worried about cracks, I suggest an epoxy resin that’s a little softer when set, and using Lexan(polycarbonate) rather than Plexiglas(acrylic). That should buy you some more time before it breaks.