[2]Tom Krupenkin, who teaches electrical engineering at the University of Wisconsin and his team want to reduce dependence on costly and polluting batteries. Instead of using batteries for power, they have turned to human beings and have placed a device in a shoe that collects and stores energy from human motion and turns it into electricity. One part of this device is an energy harvester. It has two small containers filled with thousands of very small drops of liquid. These droplets get pushed back and forth as a person walks and can directly convert it into electric power. Output of this energy is stored in a regular rechargeable tiny battery of the style that we have in cell phones.