Water

Thousands of poor homes in Manila have a problem, not uncommon for cramped and small settlements. These houses are so close together, with metal roofing that all the light is blocked off and no light reaches the homes even during daylight!

The solar bottle bulb, an innovation developed by students of the Massachusetts Institute of Technology, inspired by the Appropriate Technologies Collaborative, is helping poor communities in developing countries like Brazil and Philippines through simple and appropriate innovation.

What is the Solar Light Bulb?
It is a simple bottle bulb, usually a 1 liter soda bottle that is filled with a solution of purified water and bleach. The bottle is inserted halfway through a hole drilled in the metal roof and its sides are sealed. The whole deal looks like a bulb through a sunroof and provides a good amount of light by deflecting sunlight into gloomy interiors.