Microbial Electrolysis Cell and Clean(er) Energy

Researchers working at Penn State have produced an electrolysis cell which can be used to split simple organic compounds like acetic acid into carbon dioxide gas and hydrogen. The process occurs slowly in nature, but with the application of a voltage to the cell, the organisms essentially catalyze the reaction, making it achievable at low voltages. On one side of the cell electrically assisted bacteria produce CO2, hydrogen ions, and electrons. The electrons and hydrogen ions travel to the other side of the cell where they join to form hydrogen gas. The result is efficient use of waste products to produce a usable fuel source.

In addition, the same research group has produced another related cell that produces methane from CO2 and hydrogen. The new cell works along similar principles, and is probably more directly useful than the first cell. The capture of CO2 and its transformation into a useful fuel has obvious uses.

Both cells work at approximately 80% energy efficiency, but if they are coupled to renewable energy sources, they seem likely to provide a new source of energy. At present, they are obviously limited in scale and applicability, but it's an interesting line of research.

The most interesting part of the article, to me, was the idea that bacteria can take direct advantage of the electrons from an electric current. I would be curious to learn about the exact mechanism of this process, and how the electrons are transported into the bacteria.

http://www.sciencedaily.com/releases/2009/03/090330111257.htm
http://pubs.acs.org/doi/full/10.1021/es803531g
http://www.scientificblogging.com/news_account/microbial_electrolysis_cell_turning_bacteria_into_hydogen_machines