Currently, millions of Filipinos live without any kind of light source at all, but a band of resourceful MIT students have begun changing that. The students found that a one liter plastic bottle filled with bleach water and installed on top of a metal roof is a surprisingly simple way to light homes that have neither electrical connectivity nor natural lighting. The plastic defracts light and pushes it to every corner of a small slum house instead of beaming it onto one area like a typical lamp might. As part of their Solar Bottle Project, the organization Isang Litrong Liwanag, which means “A Liter of Light,” has already installed 10,000 of these ridiculously basic but amazing lamps throughout Manila.

 

The roofs of many Manila shacks are painted black, preventing any kind of light from penetrating what are already depressing dwellings. The solution? Plastic bottles filled with bleach and water are inserted into a hole that is cut into the metal roof, and then sealed off; the bleach keeps the water both clear and free of potential germs. Although water is sometimes scarce in informal settlements, with just a liter, the equivalent of a standard 60 watt light bulb can be installed in less than a hour and works for as long as five years! It’s hard not to love a life-altering design that also happens to cost almost nothing.