DIY: Make Solar Lights Using Plastic Soda Bottles
When I first saw this video and read the article, I could hardly believe something so simple and easy provided light to dark rooms and homes in the impoverished town of San Pablo in the Philippines. The device, invented by Illac Diaz of My Shelter Foundation, is lighting homes with minimal costs and keeping the landfills a little emptier.
I wish I knew about this device when I was paying for the electric bill every time I wanted to go into my utility shed during the day. This could have illuminated my garage, too. Darn. All that money wasted.
Just think of all the potential savings by using a soda bottle to light utility sheds, porches and more during the day. No, it will not work at night. Solar products need the sun. During the night, turn the on light conventional light. You only pay for electricity at night.
The bottles will last up to five years. Each bottle will provide the light of a 55-watt light bulb. For more lights, install more bottles. The bottles reflect the sun’s light throughout the room. Replacing them is easy. If you do not drink soda, chances are you know someone who does. You can’t beat free for a price tag.
You will need:
- · A 2-litre bottle with cap for each light desired
- · Construction adhesive
- · A 14″ square piece of roofing- vinyl, corrugated metal or plastic, wood, etc.
- · Rubber gasket material
- · Butyl tape, roofing cement or other roof-sealing material
- · Dicor lap sealant- optional
- · Jigsaw
- · Chlorine bleach
- · Insulated cap for freezing temperatures
- · Marking tools
Step One:
Remove the paper or plastic wrap from a 2-litre soda bottle. Water bottles work fine too. Pour a capful of bleach into the water. This will retard and prevent mold and algae growth for up to five years.
Measure and mark the upper 1/3 of the bottle. The roofing “flange” will fit over this mark.
Step Two:
Cut a piece of roofing material 14″ square. If your roofing material is wood, seal it against the elements. Cut out a circle slightly larger than the bottle. Insert the rubber gasket material around inside the circle. The bottle should fit tightly; this helps keep the bottle from falling out and rain from getting in.
Step Three:
Cut a circle out of the roof in the spot you want the light to hang. The circle should be large enough for the bottle to fit through and the gasket to fit tightly against. If you are placing the light in a corrugated metal roof, the ridges should match as the bottle is lowered inside. This allows the gasket to be properly sealed.
For vinyl and metal roofs, I strongly believe in products made for RVs. The butyl tape is used to seal RV windows, roof A/C’s and other items. It will withstand the elements without drying out. Replacing it is easy. Scrape it off with a paint scraper, clean the area and put new tape down.
Step Four:
Insert the bottle through the rubber gasket and glue in place with the construction adhesive. For extra protection against the elements, place a bead of lap sealant around the junction of the bottle and the rubber. It will flow into place without help. Allow to set up for 24-hours.
Step Five:
Place butyl tape, roofing cement or other roofing sealer in place and insert the bottle gasket into the ceiling hole. Apply lap sealant to the edges.
In climates with freezing temperatures, build an insulation cap from outdoor faucet covers. The method to attach it to the roof will be dictated by the type of roof used. In the spring, uncover the bottles for instant light.
This is a great project for school children, high school student, those studying ecology and energy efficiency. For those on tight budgets, this is a great way to have light and save on batteries and the energy bill at the same time.
Source: Priti Ambini, “An Innovative and Cheap ‘Solar Bottle Bulb’ Solution Lights Homes in Manila,” Ecopreneurist website, 14 September, 2011
