"daytime indoor lighting" to the homes of the poor in the Philippines, by a simple, cheap & creative method- by installing water-filled plastic pop bottles through holes in their roofs.
The Solar Bottle Bulb, as it is called, was originally designed by students from the Massachusetts Institute of Technology (MIT). Its construction and installation is simple. A clear one-liter POP bottle is filled with water, chlorine is added, then the bottle is squeezed part way through a hole in a piece of corrugated tin. A corresponding hole is cut in the tin roof of a house, the tin-and-bottle is secured over the hole so that the bottom of the bottle hangs down through the ceiling/roof, then caulking is applied to prevent rain from getting in.
When sunlight hits the roof and the top of the bottle, its rays are carried down through the water and dispersed into the interior of the home, giving off about as much light as a 55-watt bulb. Given that many of these homes lack windows, they might otherwise be nearly pitch black inside.
Not only does the system produce light during daylight hours, but it is also providing a living for locals who build and install the Solar Bottle Bulbs, and it diverts bottles that might otherwise end up in a landfill.
While the bottles don't provide light once the Sun sets, homeowners do at least have the option of performing indoor activities that require illumination during the day, when the light is available.
Additionally, For those homes who do have limited electrical lighting, the Solar Bottle Bulbs allow their owners to save costs by not using that lighting before dark.
Illac Diaz has stated that he hopes to outfit one million homes with his system by 2012. We wish him luck .
He shows us that we can MAKE a difference - in whatever small way we can !
The video below shows the installation process, and the effectiveness of the bulbs.