BEIJING, Aug. 30 (Xinhuanet) -- Scientists looking
for an alternative to corn as an ethanol fuel source have discovered
fluid from the largest chamber of a cow's stomach could be the answer to a new
kind of fuel cell, recent research reveals.
Electricity is generated in the new fuel cells
by breaking down cellulose, which can be found in waste paper, other wood
products and in the corn leaves and stalks that farms produce after a harvest.
The fluid found in a cow's rumen is rich in microbes that break down
cellulose.
"Energy is produced as the bacteria break down
cellulose, which is one of the most abundant resources on our planet," said
study team leader Hamid Rismani-Yazdi, a graduate student at Ohio State
University.
Fuel cells -- like batteries -- are energy conversion
devices, except they consume a reactant that must be replenished, whereas
batteries store electrical energy chemically in a closed system. Various fuels
can be used, including hydrogen, hydrocarbons and alcohols.
The new fuel cell contains two compartments, one of
which is filled with cellulose and rumen fluid. As the microbes break down the
cellulose, electrons are created, which flow into the other chamber of the fuel
cell, producing an electric current.
The fuel cells Rismani-Yazdi and his team created are
a refinement from an original model they created two years ago. The new fuel
cells are a quarter of the size of their original model and can produce about
three times the power ¡ª two of the cells can create enough electricity to
recharge a AA-sized battery, whereas it took four of the older generation of
fuel cells to do this.
"The power output of these fuel cells is sustainable
indefinitely as long as we keep feeding the bacteria with cellulose," said study
team member Ann Christy, also of Ohio State. "We ran these cells for three
months."
(Agencies)