Isang Litrong Liwanag (A Liter of Light), is a sustainable lighting project which aims to bring the eco-friendly Solar Bottle Bulb to disprivileged communities nationwide. Designed and developed by students from the Massachusetts Institute of Technology (MIT), the Solar Bottle Bulb is based on the principles of Appropriate Technologies – a concept that provides simple and easily replicable technologies that address basic needs in developing communities.
First, a hole is cut in a corrugated iron sheet, and a one-liter plastic bottle that has been filled with water and about four teaspoons of bleach is inserted. A hole is cut in the house’s roof, the bottle is put in, and then the iron sheet is fixed to the roof with rivets and sealant.
“Unlike a hole in which the light will travel in a straight line, the water will refract it to go vertical, horizontal, 360 degrees of 55 watts to 60 watts of clear light, almost ten months of the year,” Diaz said.
Yes, it's a bottle of water-bleach solution that one sticks in a hole in one's ceiling. It solves a problem that's difficult to imagine until you've been in a dark shed during the middle of the day. It costs pennies. It's wildly popular. How can you not love it?