Power Generation - Hydrogen and Fuel Cells: Advances in Transportation and Power - page 179

TECHNOLOGY ADVANCES
Fuel cell technology continues to advance with materials research.
The catalyst material has been one of the major expenses in fuel cell de-
sign. An anode with about 40% less catalyst has been developed at Forsc-
hungszentrum Julich GmbH in Julich, Germany. It has a bipolar plate with
areas of different catalytic activity levels. The anode substrate has one
phase that does not act as catalyst to methane-vapor reforming reactions,
and another phase where it acts as a catalyst.
The concentration of the non or slightly catalytic effective metal-
lic phase can be adjusted. A reduced catalyst concentration for a delayed
methane-vapor reforming reaction are then present if they are placed in
the fuel cell adjacent to the gas passages.
The catalyst amount is reduced, but the relative speeds of the electro-
chemical and the reformation reactions remain essentially the same.
Global Thermoelectric of Calgary, Alberta, Canada, has successfully
completed the testing of several latest generation prototype residential 2-
kW fuel cell systems. The project is part of an alliance with Enbridge, Inc.,
and will help to commercialize residential fuel cell systems.
Global has also completed the development of a 5-kW propane par-
tial oxidation (POX) reformer and has demonstrated Global's SOFC tech-
nology to use propane as a feedstock. The reformer was based on an exist-
ing natural gas fuel processor modified to reform propane. Single cell and
stack testing showed that Global's SOFCs can use propane reformate us-
ing partial oxidation reforming with only a minor impact on performance
when compared to operating on hydrogen.
Global has also designed and built a dual-stage, low-temperature
adsorbent desulfurizer. Sulfur in propane can exceed as much as 300-ppm
compared to natural gas, which ranges from 2 to 15-ppm sulfur and it
must be removed to block any poisoning of the fuel cell. The test results
indicated that no sulfur compounds were present in the outlet gas of the
desulfurizer. The system design uses a modular assembly and layout, in-
cluding a circular hot box where the fuel cell stacks and the fuel processor
are located and easily accessed.
ON-SITE POWER
A hydrogen economy may be jump started with distributed power.
These are stationary fuel cells that generate on-site power in critical ar-