It sounds relatively implausible, I know. I mean, how on earth can you build a solar panel using shiny old plastic disks? Well, this is not a “real” solar panel, but it makes good use of the CD’s reflective surface for creating a solar heating panel. It’s a very simple and efficient project that even your kids could finish in a couple of hours.
Materials required for the CD solar panel:
- super glue,
- measuring tape,
- a couple of dozen CDs (depending on the size of your window),
- a utility knife,
- a pencil,
- a clear plastic drop cloth,
- a few S hooks,
- an awl,
- black spray paint,
- masking tape.
You probably already have the gear, so let’s move it along.
Directions: The first step is to measure the width and the length of your window. Use your utility knife to cut a piece of cardboard using those measurements and adding four inches to the previous window measurements – add8 inches extra for the width and 8 inches extra for the length. For example, a 20 inch by 30 inch window will require a cardboard piece of 2 inches by 38 inches.
Next, use the black spray paint on the cardboard piece, and paint one side completely black (black is excellent for its heat retention capability). Let the paint dry completely and if necessary, add one more paint coating for best results.
In the next step, you’ll have to form a box from the cardboard piece, by cutting a four inch square from each of its corners, then bending the sides of the cardboard in such a way that the corners meet i.e. making for a box with the black painted side inside. Now you must use the masking tape for taping up the corners.
The CDs are now ready to be put inside the box in rows with the shiny metal side out. Make sure the rows are as even as humanly possible. You’ll have some wiggle room left, but that’s not a problem. Just make sure that the bottom row of CDs touches the bottom side of the cardboard box, and the same story goes for the top row – it should touch the top of the cardboard box.
Next, use a pencil for tracing the center holes of the CD rows (both top and bottom), then remove them and using your utility knife, cut the holes out. Next, you’ll glue the CDs with super glue over the holes. After that, you’ll glue down the rest of the CDs, but remember to leave a tiny space below the top and above the bottom row. Also, allow for some space below and above the center row.
It’s time to cut 4 rectangles out of the left-over cardboard, four inches wide and 3 quarters of your box’s width. Glue the rectangles into your box like maze walls, on the edge. The first rectangle will be placed above the bottom CD row/against the left side of the cardboard box, the second below the center row/against the right side, the 3rd above the center row/against the left side and the 4th below the top row/against the right side. After you’ve finished, allow the glue to dry for a few hours.
The final step is to cut a piece of plastic drop cloth, three inches longer/wider than your cardboard box then stretch it over the top, gluing it well over the sides, making it as airtight as you can. Let the glue dry overnight, then make 2 holes in the upper corners of your cardboard box and introduce S hooks in each hole.
Now you can hang the solar thermal panel on your window, preferably on a south-facing one for best results, and benefit from free heat.