A household lamp powered by bag of rocks.
More than 780 million people rely on kerosene to light their homes. But the fuel is pricey and is toxic when burned—not to mention a fire hazard. In 2008, London-based product designer Martin Riddiford and his colleague Jim Reeves decided to create a cheap, safe alternative.
Riddiford knew a falling weight could produce enough energy to run a grandfather clock, so why not a light? To find out, he attached the crank of a wind-up flashlight to a bicycle wheel. He hung a weight from the wheel to cause it to spin; the wheel cranked the flashlight, and the device lit up. Read complete story here..
Riddiford knew a falling weight could produce enough energy to run a grandfather clock, so why not a light? To find out, he attached the crank of a wind-up flashlight to a bicycle wheel. He hung a weight from the wheel to cause it to spin; the wheel cranked the flashlight, and the device lit up. Read complete story here..