The Gravity Light
Description: The Gravity Light converts potential energy that is stored in a weight into light. The principles involved in this design are very similar to the principles in a cuckoo clock, with the potential energy of the weight being converted to solar energy rather than kinetic energy. Gravity Lights can replace kerosene lights in the developing world with a safe alternative. The phenomenon can be used to illustrate the conversion of potential gravitational energy into other forms of energy. More importantly it conveys the message of sustainability and social responsibility.
Web Resource: The Gravity Light - Wikipedia, The Gravity Light Foundation