In 2002, the Brazilian mechanic figured out how to illuminate his house during the day without electricity, using nothing more than plastic bottles filled with water and some bleach.
So how does it work? Just simple refraction of sunlight, says Moser as he fills a 2L plastic bottle: "Add two capfuls of bleach, so the water doesn't turn green with algae. The cleaner the bottle, the better." He drills a hole in a roof tile with a drill. Then, from the bottom upwards, he pushes the bottle (they work work best with a black cap) into the newly-made hole. "You fix the bottle in with polyester resin. Even when it rains, the roof never leaks. An engineer measured the light - depending on how strong the sun is, it's more or less 40-60 watts."
[So just what is refraction? It's the bending of light, caused by a change in its speed. The speed of light is determined by the density of the substance through which it passes. So refraction occurs when light passes from one substance to another with a different density eg: from air to water. In the case of Moser's lights, sunlight is bent by the bottle of water and spread around the room. Science: 101!]
Moser: "Light is for everyone. Whoever wants it saves money. You can't get an electric shock from it, and it doesn't cost anything."
In the Philippines (with a quarter of the population below the poverty line, and electricity very expensive), Moser lamps are now fitted in 140,000 homes. The idea has also caught on in about 15 other countries, incl. India, Bangladesh, Tanzania, Argentina and Fiji. His idea is expected to be in a million homes by early next year!
Whether or not Alfredo Moser gets the Nobel Prize for his idea, a huge number of people around the world are benefiting from it.