Currently I'm a college student studying computer engineering, and this summer while I was on break I decided I wanted to learn more about solar energy and how to build a solar panel from scratch. My main reason for looking to build it myself was to learn how it all worked, and the next reason was due to the price of a commercially built solar panel.
So to get started, I searched around and found a few videos here and there, and a few articles on how to go about building a solar panel, but it was hard for me to find a full free video or article that showed you the full process to making a solar panel from scratch. I ended up having to watch about 4 different videos, and then having to sign up for a forum to ask other questions I had in order to get a basic idea of how to go about building my own solar panel.
It was basically an adventure for me, and mid-way into the project, I decided that while I'm learning about how to build a solar panel, and putting it together, why not create a free video to help others that want to learn about solar energy and how to build a solar panel. Of course it takes time to edit the video, and time to create a website, but I see it as a small great way of giving back.
So, you'll learn how to build a 63 watt solar system in this instructable with free videos to help you get started. I know I'm a visual learner, so hopefully most find this very helpful.
For the full video series, simple visit my website at: http://www.greentechtown.com/how-to-build-a-solar-panel-diy
Step 1: Creating A Template & Putting Frame Together
First, I want to make a template for my solar cells. What I used was a spare piece of regular plywood, a piece of regular cardboard the size of a solar cell, some tile spacers, and a staple gun to create my template. I wanted to use the tile spacers to help keep my solar cells even as seen in Part 1 of the video.
Using a ruler helped to keep everything aligned, and it's easier to cut the plywood using a jigsaw, but a regular hand saw will do fine as well.
Next, once I finished my template, I started to put the frame together. What I used was a 1x2x8 piece of plywood, and cut that to fit my outer frame of the plywood. I wanted to make sure the outer frame was not too high to prevent from loosing any sunlight I could be using. So I then placed the pieces of plywood on top of the 2x4 pressure treated plywood, and screwed those down and sanded the entire frame afterward as seen in Part 2 of the video. After sanding and cleaning up any extra dust left over, I applied the Deck and Siding paint onto the frame. I wanted to give it 2 coats for a nice seal from UV rays, and making it water resistant. I also needed to place 2 coats of the Deck and Stain paint on the 2x4 piece of pegboard.
Step 2: Assembling The Solar Cells
Next, while my first coat was drying, I started to work on assembling the solar cells. The best way to learn how to assemble the solar cells would be to simply watch the video. A quick overview of it is, the bottom of the solar cell is the positive side, and the top of solar cell is the negative side. I wanted to connect the solar cells in series, with a total of 36 solar cells, which will give me 63 watts. I used tabbing wire with a soldering iron to connect the solar cells together. For my panel I had 3 strings of solar cells. To connect those strings of solar cells, I used what is called a bus wire. The bus wire goes at the end of the strings to create one long string, however, curled up in a way like a snake. Again, for step 2, I recommend you watch the full video (Part 3) to understand how to work with the solar cells and how to check the voltage/current.
Step 3: Creating Holes For My Connections
Next, once the pegboard and plywood had 2 coats of Deck and Siding paint, I needed to screw the pegboard down inside the frame (plywood). What I did was first place the solar cells inside my frame to get an idea of where I'd need to place the screws, and then took the solar cells back out once I made my marks, and then screwed the pegboard down. Next I went ahead and drilled 2 holes at the end of my frame for my negative and positive connections to run out. You can find more about this in Part 4 of the video.
Step 4: Gluing The Solar Cells Down
Next, it was time to glue the strings of solar cells down to the pegboard with silicon. Watch Part 5 to see the method I used.
Afterward, since I had two strings completed, I was able to go ahead and solder my bus wire on one end to bond the two strings of solar cells together. Watch Part 5 and Part 6of the video to see how I went about doing this. Note* after you solder any string together, or make new connections, it is a good practice to check the voltage/current that moment, rather than waiting until you connect all the solar cells/strings together. This is also mentioned in the video as well.
Step 5: Soldering Bus Wire
Next, after hooking all 3 strings of solar cells up in series, I was ready to get my 22 gauge wires (red and black) ready for soldering. On the ends of my leads from my gauge wires, I connected some connectors to make the process of soldering them down to the bus wire a lot easier. Watch Part 7 of the video to see how I went about doing that.
To help give the inside of the solar panel a nicer look, I used 2 strips of wiremold and ran the wires inside those. This is also seen in Part 7 and Part 8 of the video. Afterward, I took the panel outside in the sun to test the voltage/current of the whole panel to make sure I was getting 18 volts and 3.5 amps in an open circuit and short circuit.
Step 6: Visiting The Electric Side
Next, in Part 9 of my video, I showed the electrical side of the solar system. Basically, what you need is a charge controller, deep cycle battery, and an inverter. To hook those up together is fairly simple as you can see in the video. I first hooked the solar panel connections up to the solar side of the charge controller, and from the battery connection side of the charge controller, I hooked that up to the deep cycle battery. From the battery, I hooked that up to the inverter, and then I was set to go. Again, watch Part 9 to see the whole process and see devices I was able to power off the solar system.
Step 7: Adding Even Pressure on the Plexiglass
Next, I found out that to secure my 2x4 piece of plexiglass I would need to provide even pressure around all the edges as you can see in Part 10 of the video. To accomplish this, I used another set of the same outer frame pieces of plywood I had on the bottom of the plexiglass, and mounted those on top of the plexiglass to provide the even pressure I needed. Be sure to drill slowly into the plexiglass to prevent from cracking the glass, and make sure you have screws that are made for pressure treated lumber. Refer to Part 10 of the video for more details.
Step 8: Installing the Junction Box
Next, in Part 11 of the video, I finished connecting my back pieces of plywood that was going to support my whole solar panel when I was ready to mount the panel on my roof. I also installed a junction box onto the back of the solar panel since most solar panels include a junction box. As seen in the video, my junction box came with a blocking diode which prevents the backflow of current when you have the solar panel hooked up to a battery. Most charge controllers prevent the backflow of current already, but if the charge controller does not, you will need to install a blocking diode onto the solar panel. It is best to install the blocking diode on the outside of the panel just in case something was to ever happen to it so you can easily replace it.
Lastly, I took my silicon and went around all my edges of the solar panel, as well as the junction box on the back. Next I made a final voltage/current check and was ready to mount the panel to my roof.
Step 9: My Thoughts of the Whole Project
Overall, the project was a fun experience, and the total amount of money that I spent was around $400-$500, which includes the battery, charge controller, and deep cycle battery. So I saved a large portion by building my own solar system, since a commercial solar panel would have cost $400 on up for just the solar panel itself.
If you have any questions or concerns, just visit GreenTechTown.com's Forum and I or other members will try to answer them as quickly as we can. This is a free resource including the videos, so be sure to share this with others.