You can build your own solar cells from scratch, but for maximum efficiency and safety, it’s best to buy professionally made systems with all the electronics in place.
If you want to save money on your solar panels, you can make your own by repurposing old, broken solar panels. One of the neat things about photovoltaic cells is that if you break one into a hundred pieces you now have a hundred small photovoltaic cells. You can get bags of damaged or broken photovoltaic cell pieces dirt cheap and assemble them into a solar cell using nothing more than plexiglass, a soldering iron, some screws, lumber, and wires.
The reason there are so many broken photovoltaic cells on the market is they’re typically thin as paper and fragile as glass. Keeping them intact is actually something of a challenge.
Start by building yourself a plain wooden box to hold your solar cell. It doesn’t need to be fancy. For a small, experimental cell, try a 12 by 18 inch piece of 3/8 inch thick plywood with some ¾ by ¾ inch pieces of wood lining the edges. This small cell will only produce enough power to charge a 12 volt battery, but building it will teach you all the principles you need to build a large home array. Every 3 inches, drill ¼ inch vent holes into your ¾ by ¾ inch liner. Nail or glue the liner to the plywood. Paint the wood the color of your choice in order to protect it from moisture and wind damage.
Cut a piece of peg board to fit inside the frame. Paint it the same color as your frame. Once the peg board dries, you’re going to use it to connect all the scraps into a single, electricity generating unit. You want to put down a piece of stiff plastic or something else you can use to carry and move your fragile photovoltaic cells.
Carefully arrange all your solar panel scraps tightly together, as neatly as possible, back side facing up. Lay the peg board on top of them. You’re going to use the peg board to connect all the scraps into a single, electricity generating unit. Get a good look at where the holes line up with the scraps.
Lift the pegboard backup and carefully apply glue or silicone based caulk to parts of the photovoltaic cell scraps. Make sure you don’t cover any parts where there are holes in the pegboard.
Carefully reapply the pegboard to the scraps and wait for the glue or caulk to dry. Once dry, let the holes guide you in arranging wire between the scraps.
Carefully solder the wire from one hole to the next, connecting all the pieces of solar cell scrap into a single unit. Carefully turn the pegboard over and gently lower it into your wooden frame. Once it’s in place, screw the pegboard directly to the frame. Your wire should extend outside the frame.
Gently lower a clear piece of plastic on top of the new solar cell and use clear caulk to secure it in place. You’ll now need to carefully connect your exposed wire to a rechargeable 9 volt battery and wait. It takes about a day to charge. As you can see, while it is possible in principle, your home made cells will lack durability and capacity. If you want to power your homes, it’s best to purchase pre–made solar cells and related supplies.