Here’s a cool adaptation of a recycled plastic soda bottle filled with water and a little liquid bleach, used to transfer sunlight into dark homes. A liter of light!
In 1879, Edison invented the light bulb, and now, well over a century later, that light bulb has become almost a neglected piece of technology in many parts of the world. (Did you know that over three million homes just outside the metro area of Manila, the Philippines have no electric power?)
This is true…no light bulbs in millions of homes, an especially ironic fact given the pace at which we learn every day about other innovations that make our life better.
Astonishing though it may be, there are some parts of the world where Edison’s light bulbs haven’t yet reached. And these are the slums in certain third-world countries. Nonetheless, the slum dwellers have found their way out — and how!
MyShelter Foundation helped them by bringing to life a sustainable lighting project that aims to deliver the eco-friendly “solar bottle” bulb to underprivileged communities. First experimented with in the Philippines, the ingenious project in the slums of Manila gives thousands of poor Filipinos solar light via plastic bottles filled with water and bleach and inserted into the roofs of their homes. The project is known as Isang Litrong Liwanag (literally, “A Liter of Light”).
Designed and developed by students from the Massachusetts Institute of Technology, the solar bottle light is based on the principles of Appropriate Technologies — a concept that leverages simple and easily replicable technologies to address basic needs in developing communities.
Here, the solar bottle light becomes an alternative source of light, powered by sunlight. The materials required are a 1.5- or 2-liter soda PET bottle, corrugated metal roofing sheets, and a mixture of water and bleach.
And so, pressed by the scarcity of electricity, people in the slums found out that they could light their homes with a bottle of water filled with water and some bleach. The bottle simply refracts sunlight very effectively, producing light power that’s equivalent to a 50/60W light bulb. On a rainy day, even without much light and no direct sun, one can still have some light.
The procedure for creating the device is very simple. You fill the empty soda bottle with purified water, add 3 tablespoons of liquid bleach and tightly seal the cap. It’s advisable not to use local tap water because over time this will allow the growth of algae. The bleach essentially “poisons” the water to keep organisms from growing and clouding the solution.. With the pure water and bleach, the solution can remain clear for up to five years.
Then make a hole in a piece of corrugated roofing material – making the hole the same size as the bottle’s circumference. Insert the bottom half of the bottle, leaving the top portion exposed to the sunlight. Make another hole on the roof of the house (the same size as the bottle’s circumference) where you want to put the solar bulb and firmly fix the device in place. Finally, seal the roof to prevent rains from getting inside the house. The device will produce light when the water inside the bottle bulb refracts and scatters sunlight or other exterior light into the interior of the house.
Thus far, there are no patents obtained on the ingenious technology; it is only hoped that a later patent grant does not disadvantage the needy.
Whoever said innovation required a fancy degree or an investment of millions? Sometimes it comes beautifully out of need, necessity and will.
The service organization driving this program is called MyShelter Foundation. Here are two links: