Planar solid oxide fuel cell single cells, removed from the frame. Source: Research Centre Jülich |
In
a new world record for stationary applications, a planar solid oxide
fuel cell (SOFC) built at the Jülich Institute of Energy and Climate
Research in Germany has exceeded an operating lifetime of 40,000 hours.
This exceeds the previous limit of commercial use in stationary
applications, and the operation corresponds to a period of 5 years.
Because of the good efficiency and high operating temperature targets,
researchers plan to develop this fuel cell type for particular
stationary applications such as distributed systems or to supply
households.
The
Jülich “stack test” fuel cell is not operated in a laboratory
environment. It has all of the components that will comprise a possible
commercial product later. It is powered by hydrogen, which is converted
with an efficiency of 64% in the cell into electricity. Other fuels such
as natural gas can be implemented with higher efficiency, as other
studies have shown. While fuel cells in vehicles are typically asked to
operate at least 5,000 to 10,000 hours, economical operation in
stationary applications require a minimum term of five years or the
equivalent of 40,000 hours. This value was surpassed for the first time
in a long-term test with Jülich’s solid oxide fuel cell.
With
this new level of performance, the fuel cell has reportedly exceeded
the expectations of researchers, who started their work two years ago to
build a fuel cell with a maximum lifetime of around 30,000 hours.
“The
test has pleasantly surprised us. Although the industrial
implementation would optimally be 60,000 to 80,000 hours, the level we
have achieved shows that the long-term stability of the fuel cell is
proved in principle,” says Prof. Detlef Stolten, spokesman of the Jülich
Research Center fuel cell.
The
test system is made from materials which could also be used for
producing a commercial product. Before that can happen, however,
researchers say the cost will need to be optimized and the system proved
not only on the test stand, but also under everyday conditions. The
Jülich Institute of Energy and Climate Research together with the
Central Institute of Technology (ZAT) aim to optimize the entire value
chain and drive market development.
The
longevity of the Jülich SOFC is partly a consequence of its relatively
mild temperature of 700 C. Customarily solid oxide fuel cells operate at
other than 800 to 1,000 C. The low operating temperature makes it
possible to use relatively inexpensive materials and to operate the cell
with a whole range of different fuels. Because of these properties,
this new SOFC could be used in distributed systems, households, and
industrial facilities, taking advantage of waste heat to supply
electricity. Also being considered by researchers are on-board power
supply applications in road vehicles, ships and aircraft.
