WANT FUEL CELLS? THINK OUTSIDE THE HYDROGEN TANK.
Energy expert advocates investing in "the other fuel cell" to reduce
reliance on fossil fuels now, not in decades.
COLLEGE PARK, Md., November 17, 2011 - When most people hear the words "fuel cell," they think
of eco-friendly, hydrogen-powered cars that emit nothing more than water.
And that, says Professor Eric Wachsman, director of the University of
Maryland Energy Research Center (UMERC), is one of the reasons we're all not
The U.S. Department of Energy's (DOE) recent decisions about how to fund
fuel cell research, he says, are putting the country at risk of falling
behind in the development and implementation of the most efficient means of
converting fuel to electricity. Fuel cells have up to three times the
efficiency of an internal combustion engine.
"There is a problem in the perception of the public and policy makers, and
in the funding of our fuel cell programs, that hydrogen and fuel cells are
linked," says Wachsman, a faculty member at the university's A. James Clark
School of Engineering. "Hydrogen-based fuel cells are the technology that
has gotten all of the press and as a result we're still waiting for a future
hydrogen infrastructure. Yes, fuel cells can run off hydrogen, but they
don't have to."
Another problem, Wachsman says, is America's fixation on vehicles. "It will
take decades to create a nationwide hydrogen distribution and storage
system, and to convert every gas station into a hydrogen filling station.
That reality has turned fuel cells into a 'future technology' and has
resulted in a drastic reduction in the funding of fuel cell research by the
DOE in favor of developing electric cars, when in fact fuel cells can be
used right now in many stationary and mobile applications, including
centralized power distribution and power generation for homes, businesses,
Most people are unaware that there are two kinds of fuel cells. The one in
the public eye, the proton exchange membrane (PEM) fuel cell, uses hydrogen
to generate power. The type of fuel cell Wachsman and his colleagues have
worked to perfect, the solid oxide fuel cell (SOFC), has a distinct
advantage over its PEM-based sibling.
"Solid oxide fuel cells are unique because they can oxidize any fuel,"
Wachsman explains. "They can run off of gasoline, diesel and natural gas
today, and biofuels and hydrogen in the future, whenever that infrastructure
is in place."
Still, nothing's perfect, and Wachsman can sum up the reason why SOFCs
aren't in large-scale production in a word: temperature.
"That is the issue," he explains. "It's the reason why the automotive
companies are using PEM fuel cells. PEM fuel cells operate at around 80
degrees Celsius [180 degrees Fahrenheit], which allows them to startup
fairly quickly. Current solid oxide fuel cells currently operate at 800
degrees Celsius [1500 degrees Fahrenheit], so it takes a long time to warm
up to operating temperature, making them more applicable to stationary power
Wachsman and his colleagues are working to change that. In the November 18
issue of Science, the team outlines the technology behind a new world record
power density SOFC that generates two watts of power per square centimeter
at 650 degrees Celsius [1200 degrees Fahrenheit]. The cell uses a bi-layer
electrolyte developed by Wachsman that is more than 100 times more
conductive than the conventional zirconia-based electrolyte operating at the
same temperature-also a world record. When the cells are assembled into a
stack they should produce three kilowatts of electricity per kilogram of
material, more than an internal combustion engine at approximately one-third
The paper lays out a strategy to further lower temperature. The team
believes its improvements to SOFC electrolytes and nanostructured-electrode
designs could ultimately reduce the cells' operating temperature to only 350
degrees Celsius [660 degrees Fahrenheit]. At that temperature they could
start up fast enough for automotive applications, and would be more
efficient and more affordable than current SOFCs because they could be
manufactured from less expensive materials.
PROGRESS AT RISK
The DOE's 2012 budget request, however, does not include funding for the
SOFC program, effectively eliminating it from the agency's research
priorities and greatly reducing funding options for groups like Wachsman's.
This decision, he believes, was made without a complete understanding of
recent significant advances in SOFC technology such as those described in
the Science paper, which, combined with their fuel-flexibility, put them in
an ideal position to improve nationwide energy efficiency today.
In the current issue of Energy and Environmental Science, Wachsman and his
colleagues, Craig A. Marlowe and Kang Taek Lee, make the case that SOFCs
should be an integral part of our energy policy. SOFCs, they argue, meet all
of the DOE's six key energy strategies: they deploy clean electricity, make
use of alternative fuels, help modernize the power grid, will help gradually
electrify the vehicles we drive, increase vehicle fuel efficiency, and
increase building and industrial efficiency.1
"We don't have to wait for hydrogen," says Wachsman. "SOFCs represent a
solution for everything that you can think of in terms of producing
electricity and power today."