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This clean, quiet and flexible technology is already beginning to serve humanity in a variety of useful ways. But production volume is low and costs are too high. Public support is needed to help generate initial demand to break this cycle.
Fleet vehicles, in particular urban transit buses, represent an early entry route into the transportation market.
This is due to several factors: conventional buses are significant sources of noxious emissions in urban areas; central fuelling depots will facilitate the use of hydrogen; and, fuel cell buses are expected to have lower maintenance and operating costs.
Several fuel cell buses are being demonstrated in public transport systems. An event of special significance occurred on 16 March 1998, when fare-paying passengers in Chicago boarded the world's first fuel cell bus to enter revenue service. Compressed hydrogen fuels the engine, providing a range of about 250 miles. The bus has equivalent performance to a conventional diesel without the growling engine and unhealthy emissions.
Hydrogen fuel cell buses are now sufficiently technically advanced to enter the market but extensive field demonstration and fleet testing is required to prove performance and build confidence in the technology.
Light-duty automotive applications are by far the largest market opportunity available to fuel cell technology and have been the focus of intense development effort. All major automakers now have fuel cell vehicle programmes. Most have either launched prototype cars or announced their intention to do so.
A major milestone was achieved on 17 March 1999 with the launch of a prototype fuel cell car, based on the sub-compact Mercedes A-class. Described as the first viable fuel cell car, NECAR IV demonstrated that fuel cell technology had advanced to the point where it met the high performance and compact size needed for automobile propulsion -- the complete fuel cell engine and components are all contained in the double-skinned floor. The car's energy efficiency is reported to be close to double that of the diesel version. Liquid hydrogen tanks provide a range of 280 miles.
DaimlerChrysler has indicated that the technology has the possibility to be maintenance free and that mass-produced fuel cell cars are expected in 2004. GM, Ford, Toyota, Nissan and Honda have targeted similar dates.
On-site fuel cell generators are already providing heat and power to hundreds of buildings across the world.
When costs fall to competitive levels, these small fuel cell cogeneration systems are expected to take a growing share of the market for power equipment. The development of small (3kW-10kW) fuel cell systems for residential use is the focus of increasing effort as they are expected to provide the householder with electricity and heat at a significant saving over conventional services.
Fuel cells make distributed cogeneration a competitive alternative as they provide a unique combination of advantages. Being small, clean and quiet, they can be sited wherever electricity is needed, even in the most congested urban location. This allows utilities to meet new or peak demand for electricity without building central stations and without substantially expanding or upgrading the power delivery system -- and so avoid the large transmission. Moreover, distribution losses are eliminated or reduced as is the need for unsightly power lines and associated electromagnetic radiation. Fuel cell systems are modular and so capacity can readily be expanded to follow load growth. Siting flexibility also allows by-product heat to be used, doubling energy efficiency.
A number of fuel cell systems (200kW ONSI PC25) operating in "real world" commercial conditions have run continuously at full power for more than a year and have exceeded 40,000 cumulative operating hours. Reliable operation combined with infrequent servicing intervals reduces maintenance cost and interrupted power supply associated with conventional equipment. Fuel cell generators have been sited in hospitals and computer centres where there is a need for uninterruptible, high quality power.
There is also a growing interest in micro fuel cells as portable generators and to replace batteries. Compared to batteries, fuel cells are quick and easy to refuel, have longer operating times and lower operatng costs. Systems have been developed for a number of applications, including portable computers and telephones, video cameras and generators for camping, boating and emergency power.
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