How to Build a Solar Panel

Most solar cells are made of silicon or similar materials and are sold pre-packaged. However, you can construct a do-it-yourself solar cell very inexpensively out of common materials found at any hardware store. While not as efficient as a more sophisticated panel (which requires professional factories and expensive materials), it can demonstrate the concept of a solar panel and can also be used as a functional light detector.

Things You'll Need

• Electric stove or hot plate
• Copper sheeting
• Sheet-metal shears
• Micro-ammeter capable of reading currents lower the 50 microamperes
• Sandpaper
• 2 alligator-clip leads
• Clear plastic bottle
• Water
• 2 tbsp. salt

Instructions

1. Cut two rectangular pieces of copper sheeting, each approximately the size of the stove burner.

2. Wash one piece of the copper thoroughly, and then use the sandpaper to clean off any corrosion.

3. Lay the copper sheet down on the burner.

4. Turn the burner to maximum heat.

5. Monitor the copper carefully. It will change colors as it begins to oxidize, slowly transforming to black.

6. Leave the copper on the burner for at least 40 minutes, or until it has a thick coat of oxidized black material.

7. Turn off the heat on the burner and allow the copper to cool in the air. This should take another 20 to 30 minutes.

8. Gently scrub the copper with your hands under running water to take off the most easily removed pieces of the oxidized coating. Do not try to remove all of the coating or scrub too hard. Your goal is to take off what can easily be removed, but not to damage the remaining copper below the oxidized layer, which is required to build the solar panel.

9. Cut off the top of the plastic bottle so that it forms a makeshift bucket.

10. Take the second piece of copper (the one you didn't heat up), and bend it slightly to fit the contours of the bottle.

11. Slide the second piece of copper into place along the inside of the bottle.

12. Repeat the process with the first piece of copper (the one you heated up). The two pieces of copper should not be touching each other.

13. Connect an alligator-clip lead to each piece of copper.

14. Connect the alligator-clip lead from the second (uncooked) piece of copper to the positive terminal of the micro-ammeter.

15. Connect the alligator clip lead from the first (cooked) piece of copper to the negative terminal of the micro-ammeter.

16. Stir the salt into several cups of hot water until the salt is completely dissolved.

17. Slowly pour the salt water into the bottle, taking care to keep the two alligator-clip leads dry. Make sure you leave at least an inch of the copper pieces above the water line.

18. Check the needle on the micro-ammeter. The apparatus you've constructed is essentially a battery, so there will be some charge whether it is in light or darkness.

19. Place the apparatus in sunlight and observe how the charge increases as the cell converts the sun's energy to electricity.

Tips & Warnings

• This is a very small solar panel, suitable for demonstrations. It cannot power large appliances.

• Visit the Biggin Hill website to learn how to build a working solar panel (see Resources below).

Resources

• Biggin Hill to build a functional solar panel