First, there's dirt.Aviva Presser Aiden of Harvard's School of Engineering and Applied Sciences has developed a phone charger that gets it power from microbes in soil. It turns out that soil microbes produce free electrons during the normal course of munching on and digesting soil. Her simple and inexpensive device has a conductive surface and a cathode that captures the electrons and shuttles them to battery. The device could be perfect for people living in areas not connected to an electrical grid, such as Sub Saharan Africa. Aiden recently won a $100,000 grant from the Bill and Melinda Gates Foundation to take the idea to its next level.
But why resort to dirt, when you could just blab and blab and blab and automatically charge your phone? A team in South Korea is working on way to harvest energy from the tiniest movements and vibrations generated by people breathing, walking or talking. The researchers propose using the zinc oxide fibers that expand and contract when they vibrate. The expanding and contracting generates a charge, which is captured and stored in a battery.
Discovery News 5.12.11