This step is pretty much as easy as it sounds: just add water (tap water works) to your mud battery until the soil within it is completely saturated with water. The benefits of mud over dirt in this battery aren't immediately presented; to see the increased voltage one must allow the battery to incubate overnight.
You actually can power electric devices with just mud! Are you curious about how this works? You need some little helpers in the soil— bacteria —that are able to turn their food sources within the soil into electricity in a device called a microbial fuel cell. But is this possible with any soil and does the soil type matter at all?
Monitor and compare the power output of two microbial fuel cells using two different soils. To turn soil into a battery, the most important thing you need is lots of little helpers—so-called electrogenic bacteria —that help generate electricity.
With the usage factor of the selection of mud for this microbial fuel cell. humans need food to live. Bacteria get this energy in a two-step process. The first step requires the removal of oxygen or nitrate. If certain bacteria are grown under they can transfer electrons to a carbon electrode (anode). and oxygen to form water.
When packing the mud in the microbial fuel cell, pat down the mud and electrodes, as described in the Setting Up the Microbial Fuel Cells section of the Procedure, so that you do not have any trapped air bubbles in the mud.
After several weeks, the researchers identified the microbes that were growing on the mud-implanted electrodes. To their surprise, Lovley and his colleagues found that one type of microbe— Desulfuromonas acetoxidans, from a family called Geobacteraceae—had all but taken over the battery electrode, ousting the others.