Wednesday, September 14th, 2011
The video above is one of several on YouTube.com showing how discarded two-liter plastic soda bottles are being turned into skylights that instantly raise the quality of life for people in severe poverty.
The videos reveal areas of the Philippine Islands and Brazil where people live in small buildings so close together that the inside is almost totally dark both day and night. Electricity is rarely present and if so must be used sparingly. Almost nothing can be done inside the dark houses. Skylights made of discarded plastic soda bottles change that in an instant. In these regions, recycling anything is rare; reusing things is far more common.
Though its origin is not certain, the idea is as clever as it is simple. Start with a discarded two-liter PET (polyethylene terephthalate) soda bottle, fill it with water, and add two capfuls of bleach to prevent bacteria and algae. Fasten a collar to the bottle and insert it in a hole cut in a metal roof, with the bottom three quarters of the bottle inside. The collar fastens to the roof and keeps the bottle from falling through.
Then comes the magic: sunlight strikes the top of the bottle, is refracted by the water, and illuminates the room below. Each skylight-bottle provides light equivalent to a 50- or 60-Watt incandescent bulb.
Besides lighting home interiors, multiple bottle-lights also are being used to light schools and other buildings in these areas. It is a practical solution to a widespread need, and it is obviously economical. Solar tubes selling for around $400 apiece (plus installation) admittedly are higher tech, but the joy that the almost free bottle light brings to the faces in the videos, that’s priceless.