They could if it runs on hydrogen, and the research efforts of Penn
State environmental engineers working with a scientist from Ion
Power, Inc. pan out.
The researchers have applied electricity to bacteria and quadrupled
the amount of hydrogen a microbial fuel cell (MFC) can produce compared
to straight fermentation.
They call the combination a BioElectrochemically-Assisted Microbial
Reactor or BEAMR, and it would sound like science fiction if it wasn't
working in the lab.
The bacteria used for the BEAMR was originally developed to clean
wastewater and produce electricity. By keeping oxygen away from the MFC
and introducing a small amount of electricity (.25 volts), the process
bypasses the "fermentation barrier and converts and converts a
"dead end" fermentation product, acetic acid, into carbon
dioxide and hydrogen."
Bruce Logan, the Kappe professor of environmental engineering and a
co-inventor of the new process, claims it "demonstrates for the
first time, that there is real potential to capture hydrogen for fuel
from renewable sources for clean transportation."
The BEAMR isn't restricted to "carbohydrate-based biomass"
for hydrogen production.. In theory, the MFC can produce hydrogen from
"human, agricultural or industrial wastewater" and leave the
wastewater clean. And it uses just ten percent of the voltage needed for
electrolysis.
Electrolysis, the traditional method of separating hydrogen from
water using electricity, is often called a roadblock preventing a
hydrogen economy truly friendly to the environment. It requires large
amounts of electricity, most of which comes from sources such as oil and
coal. If the BEAMR can produce comparable amounts of hydrogen with one
tenth the electricity, it could be a boon for the emerging fuel.
But Logan doubts that the hydrogen generating microbial fuel cell he
helped invent can single-handedly bring a global hydrogen economy into
existence. He claims there's just not enough "waste biomass to
sustain a global hydrogen economy."
The paper describing the process "Electrochemically
Assisted Microbial Production of Hydrogen from Acetate" is
available online, and will be published in a future edition of
Environmental Science and Technology.
You can read the Penn State announcement "Microbial
fuel cell: High yield hydrogen source and wastewater cleaner."
For more stories on Fuel Cells, check out ExtremeFuelCells.