The Grass Is Greener On The Other Side

Researchers at Penn State University have developed a process whereby bacteria is used to extract Hydrogen from almost any biodegradable organic substance (from grass clippings to wastewater).

The discovery, published in Proceedings of the National Academy of Sciences, is very promising given that the researchers were able to use existing technology meaning the process can be put to use immediately.

Professor Bruce Logan and his research assistant Shaoan Cheng discovered a method whereby bacteria called exoelectrogens break down acetic acid (produced by fermenting cellulose, glucose or other biodegradable organic matter) in a microbial electrolysis cell to create Hydrogen.

The way the process works is that when the bacteria consume the acid, electrons are transferred to a graphite anode. During the process the bacteria also release protons (which are Hydrogen atoms stripped of electrons) that are held in solution. As the electrons are then transferred to a platinum cathode they combine with the protons and generate 0.3 volts of electricity. When another 0.2 volts is added to the process it creates Hydrogen gas.

This is all very promising especially given that this method produces up to 82 percent more energy than the electricity and biomass needed to produce it.

http://www.wired.com/cars/energy/news/2007/11/hydrogen_bacteria