British industrial design company Therefore have developed LED-powered GravityLight, to ensure the world’s developing countries have access to affordable and safe lighting. The GravityLight was designed by Therefore directors Martin Riddiford and Jim Reeves. And it is designed to be suspended from a ceiling or wall in a home. Using a nine-kilogram bag of sand or rocks, a piece of rope can be pulled through a mechanism which generates electricity.  The LED light works on the gravitational pull from the lamp and once the bag of sand is pulled; a three s...