Introduction
Building your own solar panel from discarded materials can be a fun and rewarding DIY project. Not only can you save money by repurposing old electronics, you'll also learn about how solar energy works along the way.
In this comprehensive guide, I'll walk you through each step of the solar panel building process. I'll cover what materials you'll need, how to construct the panel frame, how to wire the solar cells together, and how to weatherproof your finished solar panel.
Whether you're an aspiring solar enthusiast or just looking for a weekend project, read on to learn everything you need to know about constructing a functional solar panel from scrap.
Gather the Necessary Materials
The first step is gathering up the components you'll need to build your solar panel. Here's a list of the basic materials:
Solar Cells
The heart of your solar panel will be an array of solar cells. These are the components that actually convert sunlight into electricity.
The most common type of solar cells are made from silicon. You can salvage old silicon solar cells from broken solar panels, garden lights, or even calculators. Look for cells that are at least 3 inches wide. You'll need around 36 cells for a small 12-volt solar panel.
Panel Frame
To house the solar cells, you'll need a rigid frame for your panel. This can be made from scrap wood, PVC, metal bars, or other materials you have on hand. The frame should be the dimensions of your finished panel. For 36 cells, a frame approximately 2ft by 4ft will work well.
Transparent Cover
The solar cells will be covered by a transparent material that allows sunlight to pass through. Old window glass, acrylic sheets, or plastic covers can be used for this. Make sure the covering is as transparent as possible.
Copper Wire
To connect the solar cells together, you'll need copper wire. Use wire that is at least 16 AWG gauge so it can handle the electric current. Solid core wire works best.
Soldering Iron and Solder
Soldering equipment is necessary to connect all the solar cell tabs together. Use rosin core solder and a 30-watt soldering iron.
Silicone Sealant
Once the panel is assembled, silicone caulk or sealant will be used to waterproof all edges and wire connection points. Make sure it's 100% silicone.
Bolts, Washers, and Nuts
Use stainless steel hardware like bolts, washers, and nuts to mount the solar cells to the frame and hold the cover in place.
Construct the Panel Frame
Once you've gathered the components, it's time to start building the solar panel frame. Follow these steps:
Measure and Cut the Frame Pieces
Cut your frame material to the desired dimensions for your panel. For a 36-cell panel, cut two pieces that are 2ft long and two pieces that are 4ft long.
Use a saw to make straight, clean cuts. Wear protective eyewear when cutting.
Join the Frame Pieces at Right Angles
Arrange the frame pieces on a flat surface so they form a rectangular frame. Use corner brackets, wood screws, or bolts to join the pieces at right angles.
Make sure the frame is square by measuring the diagonals - they should be equal.
Add Supports Across the Back
Cut 2-3 support pieces that span the width of the frame. Attach them across the back of the frame using screws or bolts.
Space the supports evenly to prevent sagging when the solar cells are added.
The frame is complete and ready for installing the solar cells!
Mount the Solar Cells
Now it's time to mount the solar cells to the panel frame. Follow these steps carefully:
Lay Out the Solar Cells
Arrange your solar cells in rows on a flat work surface. Place them close together so the rows butt up end-to-end.
For a 36-cell panel, make 3 rows of 12 cells each. Make sure all the cells face the same direction.
Secure the Cells to the Frame
Lift a row of cells and place it on the frame. Position the cells centered side-to-side and bottom-to-top.
Drill pilot holes through the pre-drilled tabs on the cells. Secure each cell with stainless bolts, washers and nuts.
Repeat for the other 2 rows. Your solar cells are now securely mounted!
Wire the Solar Cells Together
With the cells mounted, it's time to connect them into a circuit by soldering their tabs together. Follow this process:
Connect Cells in Each Row
Solder ** jumper wires between the negative and positive tabs along each row of cells. This connects them in series**.
Make sure the connections are fully soldered. Add extra solder if needed to strengthen the joint.
Connect the Rows
Solder longer jumper wires from the end of one row to the start of the next row.
Connect positive to negative to link the rows in series. This builds up voltage.
Solder on the Output Wires
Cut two longer output wires and strip 2 inches of insulation from the ends.
Solder one wire to the negative tab of the first cell. Solder the other wire to the positive tab of the last cell.
These will connect your panel to the load you want to power.
Apply Silicone Sealant
At this stage, your solar panel is electrically complete! Now you just need to protect it from the elements:
Seal the Edges
Run a continuous bead of silicone around the inside of the frame. Use a caulking gun to control the flow.
Seal both the front and back edges to prevent moisture from entering.
Seal Wire Joints
Apply small dabs of silicone on top of each solder joint. This prevents corrosion from water.
Also cover the entire back of the cells to hold them firmly to the frame.
Let the Silicone Cure
Allow the silicone 24 hours to fully cure before further handling. The fumes can also be harmful, so work in a well-ventilated area.
Add the Transparent Cover
The final step is attaching the transparent cover to protect the solar cells:
Cut the Cover to Size
Measure the inner dimensions of the frame. Cut your transparent sheet (acrylic, plastic or glass) to size using a handsaw or glass cutter.
Wear protective gear like gloves and goggles when cutting.
Secure the Cover
Place the cut transparency over the frame. Drill pilot holes through the cover and frame. Secure it with stainless bolts, washers and nuts.
Don't over tighten, as this could crack the cover. Your solar panel is complete!
Use and Maintain Your Solar Panel
Once assembled, here are some usage and maintenance tips:
-
Place the panel in direct sunlight to maximize power output.
-
Use a charge controller to regulate power into your battery.
-
Check wire connections periodically for corrosion. Re-solder as needed.
-
Clean the transparent cover every few months using a soft cloth and mild cleaner.
-
Avoid puncturing the cover as this will allow water damage.
-
You can connect panels in parallel to increase current.
With proper care and usage, your home-built solar panel can provide free, renewable power for years to come!
Conclusion
Constructing your own functional solar panel from discarded materials is very achievable. By following the steps outlined in this guide, you can repurpose old electronics into a working solar energy system.
The ability to harness the sun's power yourself is invaluable. Not only will you save money, but you'll learn so much through creating your own solar project.
So don't let those old solar cells and scraps go to waste. Grab your soldering iron and put together a DIY solar panel using the techniques covered in this article. The sun provides limitless energy if you know how to capture it!