Illac Diaz in a home equipped with one of his Solar Bottle Bulbs (Photo: Isang Litrong Liwanag)
Perhaps you’ve performed that old camping trick before, where you created a lantern by shining a flashlight into a water-filled bottle. While that may have helped you find your marshmallows in the dark, imagine how much brighter that bottle would have been if it were lit directly by the Sun. Bright enough, it turns out, that it could brilliantly light up the interior of a one-room house. That’s the idea behind the Isang Litrong Liwanag (A Liter of Light) project – it’s bringing daytime indoor lighting to the homes of the poor in the Philippines, by installing water-filled plastic pop bottles through holes in their roofs.