Battery manufacturing works with animal dung

Bacteria in waste, including animal manure, can help generate electricity, according to new research by US scientists.

Researchers at Stanford University in California have created a special "battery" that works by bacteria and produces electricity as they digest biological material.

In the research report published in the journal Proceedings of the National Academy of Sciences, scientists from Stanford describes how can use "battery bacteria" to decompose pollutants in lakes as well as the coastal waters.

According to US researchers, "bacterial batteries" help clean waste water and help generate electricity to offset the energy consumption in the process. (Corbis)

At present, their "bacterial cell" prototype is about the size of a small battery, often used in chemical experiments with two electrodes (one negative and the other positive) embedded in a bottle. The wastewater is filled with bacteria.

When bacteria eat organic material in waste water, these bacteria will cling to the battery's cathode, producing electrons. The battery's anode immediately "collects" these electrons, producing electricity.

Over the years, scientists have known about the existence of exoelectrogenic microbes - organisms that evolve in the absence of air and develops the ability to react with oxide minerals instead of oxygen. Organic nutrients into biofuels.

Some teams have tried but failed to turn these microorganisms into "biological generators." However, the new "bacterial battery" invention of Stanford scientists has been shown to be effective in forcing exoelectrogenic microorganisms to work.

Despite its simple design, the "bacterial battery" can harness about 30 percent of the potential energy in waste water, equivalent to the existing solar panels.

Researchers acknowledge that the potential energy in waste water is far less than the sun's rays, but the extraction process will have the added benefit of clearing water sources. They claim that bacterial cells can offset the amount of electricity currently used to treat wastewater, which accounts for about 3 percent of all electricity consumed in developed countries.