It may seem hard to believe that bacteria could produce electricity, yet some bacteria have managed to do just that. You probably know that an electric current simply consists of electrons that are moving through or in a conductor. When we use electricity to power a motor or heat the filament of a light bulb, we don’t actually “use up” any of these electrons. We just use some of their energy to do something we find useful. Bacteria produce electricity in much the same way that a battery uses chemical reactions to produce electricity. Batteries have two poles, or terminals; these are as electrodes. One is positive, and one is negative. Electricity flows from the negative terminal to the positive terminal. For example, when you start your car, turning the key connects the two terminals of the battery via an electrical pathway that goes through the starter motor’s coils. Current–electrons immediately flow from the negative to the positive terminal.
These activities will help you walk your students through two major principles involved in fuel cell creation. They will learn what a battery is and how energy can come from in living organisms.
For additional Bioenergy lessons visit: http://agsci.oregonstate.edu/bioenergy-k-12/bioenergy-lessons