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  Fuel cells : a market for tomorrow?
Fuel cells seem poised to become tomorrow's ideal energy conversion device.
Developments in regulation (liberalisation for utilities and networks, strict
rules for environment protection) will make the use of fuel cells attractive, if
not necessary. At the same time developments in technology have enabled them to
become performing, reliable and maybe economic.
The large car manufacturers are now committed
Emission standards are becoming increasingly strict in the USA and Europe,
and many other countries may follow suit, in particular in Asia. As a means of
complying with these standards fuel cells have become a critical issue, and most
large car manufacturers have embarked on large-scale R&D programmes to
develop fuel cell cars and to bring them onto the market by 2003-2005.
The manufacturers have grouped together to do this. Daimler Chrysler formed a
partnership with Ford, Mazda and the Canadian fuel cell manufacturer Ballard.
Toyota and General Motors have teamed up, probably using Toyota's in-house
developed fuel cell technology. These two groups, with their associated
companies such as Volvo, Jaguar, Mitsubishi, or Fiat, Subaru, Isuzu,
respectively represent 30% and 26% of the world car production. They have
committed themselves to bringing commercial fuel cell vehicles onto the market
in 2004, with investment programmes of about a billion $ each.
Honda appears still to be going it alone, and is also announcing a fuel cell
car for 2004 with in-house fuel cell technology. Renault has acquired fuel cell
development work with Nissan, but has not yet clearly announced their strategy
in this field.
In Europe Volkswagen and PSA are involved in European projects (like FEVER or
CAPRI) with the Italian fuel cell manufacturer De Nora, but they have not
announced a commercial vehicle yet. BMW is working on a fuel cell
"APU" (auxiliary power unit) that would provide the energy
increasingly needed in cars for non-traction purposes. Delphi is also working on
fuel cell APUs.
The last chance for electric cars?
Everyone seems to have given up battery vehicles as a lost cause. They failed
to come up with adequate range, speed, recharge time, and cost. The ZEV (Zero
Emission Vehicle) imposed by Californian legislation is probably a stillborn
concept. In any case the concept only really transferred the emissions problem
from the vehicle to the electric generating station.
Hybrid vehicles seem more promising. They combine an optimised ICE (internal
combustion engine) with batteries, a design that enables significant reductions
in emissions, without affecting range or speed, and avoiding the battery
charging challenge.
Fuel cells can replace the ICE in such a hybrid configuration, enabling a
further significant reduction in emissions.
Fuel cells are a clean technology, up to a point…
Fuel cells were used as energy sources in all the American manned space
flights (Apollo, Gemini, Orbiter…). In addition to electricity, they provided
drinking water for the cosmonauts. Unfortunately fuel cell technology used down
on earth is not quite so pure.
The principle of fuel cells is the opposite of electrolysis, by which an
electric current dissociates water into oxygen and hydrogen. In fuel cells
oxygen and hydrogen are combined in the presence of catalysts to form water and
an electric current. In space applications liquid hydrogen and oxygen were used,
with fairly large quantities of platinum catalyst.
But applying this technology to vehicles is not so simple. Air is used
instead of oxygen, but this reduces cell performance, and also creates problems
with the CO and CO2 in the air. Also using pure hydrogen in a car means solving
complex storage, distribution and refuelling problems. Moreover hydrogen must
first be manufactured, which like battery cars only displaces the emission
problem from the vehicle to the hydrogen plant.
The problem is to find a convenient fuel that can be used in vehicles, and
then to extract the hydrogen from this fuel with an on-board reformer. The most
popular choice would be petrol or Diesel, but these fuels are difficult to
reform and they contain a lot of carbon which must be got rid of. Today methanol,
an easily reformed liquid fuel, seems to be a widely accepted compromise. But
methanol production is small (less than 30 million tons world-wide), and the
distribution network needs to be adapted. And naturally the global efficiency of
the system diminishes with losses in methanol production and reforming.
Direct methanol fuel cells are being developed, which use methanol without
reforming it. This would be the ideal solution, but these devices have
significantly lower performances, which makes them larger and globally less
efficient.
Different technologies for different markets?
Fuel cells were invented as long ago as 1839. More than a century and a half
later they seem ready at last to become commercially viable products. This is
due to the combined effects of technological developments in materials
(membranes, ceramics, catalysts…), deregulation of the electricity supply
system, and introduction of strict emission standards.
Several different fuel cell technologies are being developed. Low or medium
temperature fuel cells are the most advanced technologies, and have reached the
commercial or pre-commercial stage. Alkaline fuel cells (AFCs) were the
favourites for space applications, but today polymer membrane fuel cells (PEMFCs)
are preferred for mass-market applications such as cars. Phosphoric acid fuel
cells (PAFCs) are a mature technology well adapted to stationary cogeneration
applications. Over 300 units have been sold throughout the world, mainly in the
USA and Japan, at a price of around 3000 $/kW.
High temperature technologies (MCFCs and SOFCs) are more delicate to manage,
but they can use common fuels such as natural gas and reform them internally.
They are particularly well adapted to stationary applications in which the heat
generated can be used in combined cycle or cogeneration. These technologies are
still in, the experimental stage, but they could appear on the market by
2001-2003.
There are three market segments for fuel cells. The automotive segment will
offer a massive market for PEMFCs if fuel cell vehicles prove a commercial
success. But success in this segment is subject to severe conditions. Cost must
not durably be higher than ICE vehicles, , which sets a goal of 50 $/kW,
compared to present costs that are probably nearer to 3000 $/kW. Attaining this
goal will require production volumes of at least 200 000 fuel cell vehicles a
year, which cannot realistically be expected before 2007-2008. Moreover
reliability must be at least the same as that of present vehicles.
The second major market is stationary applications. This would seem to be the
favourite market for high temperature technologies, but PEMFCs are also aiming
for this market even though their low operating temperature makes them less
obviously adapted to cogeneration. Fuel cells in stationary applications would
not replace the present large electricity generation stations. They would rather
enable new network architectures privileging distributed generation. Generating
electricity where it is used has two major advantages. On-site cogeneration (combined
heat and power generation) gives overall efficiencies of 80%, and distributed
generation reduces the need for extremely costly transmission and distribution
networks. The cost objective is higher than in automotive applications, around
1000 $/kW. This market does not only concern professional generation, but also
residential generation. Several players (Plug Power with PEMFCs, Sulzer Hexis or
Ceramic Fuel Cells with SOFCs) are aiming for the residential market with
devices providing electricity, heating or cooling for houses.
The third segment is more diverse, and comprises portable applications and a
number of niche applications. As in space, in such applications convenience is
the prime factor and not cost. Motorola and Los Alamos National Laboratory are
working on a methanol fuel cell for mobile phones fuelled for one week by a
single ink-pen type cartridge. Siemens has equipped the new generation of German
submarines with PEMFCs to increase their range for submerged missions. A number
of other niche applications can be listed, such as camping, sailing, isolated
sites, weather or environment monitoring stations, portable or mobile military
applications…
A fuel cell industry is emerging
A new fuel cell industry is coming into existence. It is specially developed
in North America, where it was fostered by large government R&D programmes.
The Canadian Ballard and IFC (a UTC-Toshiba joint venture) are dominant in
PEMFCs, followed by a number of challengers such as H Power or Plug Power.
Moreover Du Pont has a virtual monopoly over PEMFC membranes with its Nafion
membrane. IFC was also the leader in AFCs, whereas in PAFCs ONSI (another
UTC-Toshiba joint venture) probably holds 80% of the world market. In SOFCs
Westinghouse is leader, and in MCFCs the Americans MC Power and FuelCell Energy
are probably first.
In Japan the situation is rather different. Mostly fuel cell development was
undertaken by the large manufacturers of electrical equipment such as Fuji,
Hitachi, IHI, Mitsubishi, Toshiba, or by the car manufacturers (Honda, Nissan,
Toyota…).
In Europe R&D expenditure on fuel cells is significantly lower than in
the USA or Japan. Work on AFCs was dropped when the European Hermes space
shuttle programme was abandoned. However ZeTek is now trying to apply this
technology to vehicles. Siemens developed PEMFCs for German non-nuclear
submarines, and in Italy De Nora provides PEMFCs, in particular for European
programmes such as the FEVER fuel cell vehicle. Alstom concluded an agreement
with Ballard to develop stationary applications for PEMFCs in Europe, with a
manufacturing site in Dresden (Germany). In SOFCs Siemens has become world
leader after acquiring Westinghouse, but the technology will be developed in the
USA. In Switzerland Sulzer Hexis is developing small SOFCs in the kW range for
residential applications.
Today European fuel cell manufacturers do not seem well placed to get into
the automotive market. Daimler Chrysler has chosen Ballard together with Ford (who
now owns Volvo and Jaguar). Fiat is now likely to join General Motors using
Toyota fuel cells. Renault now has in-house fuel cell resources with Nissan.
Siemens and De Nora will have hard work before them if they want to be in this
market. |
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