Fermentation barrier

Newindpress reports Scientists have managed to coax bacteria into producing hydrogen - a development that would reduce the cost of waste water treatment. Using a little amount of electricity - about 0.25 volts - scientists at Pennsylvania State University found that a microbial fuel cell can overcome its "fermentation barrier", Xinhua reports.

The voltage is just one-tenth needed for electrolysis - the process that uses electricity to break water down into hydrogen and oxygen. "Basically, we use the same microbial fuel cell we developed to clean waste water and produce electricity. However, to produce hydrogen, we keep oxygen out of the microbial fuel cell and add a small amount of power into the system," said Bruce Logan, a professor who led the study....

The voltage to be given, scientists explain, is a small fraction of the voltage needed to run a typical six-volt cell phone. But it overcomes the "dead end" created during fermentation and produces four times more hydrogen than would be typically generated by fermentation alone. Besides, the new process is not limited to using only carbohydrate-based biomass. Theoretically, it yields hydrogen from any biodegradable, dissolved, organic matter and cleans wastewater. In the procedure, when the bacteria eat the biomass, they transfer electrons to an anode. The bacteria also release protons - hydrogen atoms stripped of their electrons - which go into solution.

The new process demonstrates, for the first time, the real potential in capturing hydrogen from renewable sources.

Science Daily reports This new process demonstrates, for the first time, that there is real potential to capture hydrogen for fuel from renewable sources for clean transportation

The problem with cars using fuel cells is that it takes too much electricity (produced from oil, natural gas, coal, or nuclear power) to generate the hydrogen, but this discovery may make fuel cell cars reasonable in the future.