PEM fuel cell cars

As most current automotive fuel cell efforts use proton exchange membrane (PEM) fuel cells, these will be described in a little more detail in this section and will be used as templates for the performance calculations presented in section 4.1.3. A typical passenger car PEM fuel cell system is depicted in Fig. 4.2. Included are heaters for bringing the equipment from ambient temperatures to the operating temperature of around 80°C and humidifiers for ensuring the level of water in the membrane and electrode areas required for 

A step further advanced is the concept proposed by General Motors (Fig. 4.4), where not only all fuel cell equipment is placed below the passenger cabin, but this skateboard is isolated from the cabin and receives all in- 

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Phase 3 Introduce pem fuel cell cars for private transportation. 

Sorensen, B. (2004d). Total life-cycle analysis of PEM fuel cell car. In "Proc. 15 World Hydrogen Energy Conf., Yokohama". 29G-09, CD Rom, Hydrogen Energy Soc. Japan. 

Additionally, there are ample natural gas resources in the Los Angeles area, writes Ogden. The 55 million scf/day needed for the initial 350,000 PEM-fuel-cell cars could be produced by steam reforming about 22 million scf/day of natural gas— less than 1 percent of the total natural gas flow through Southern California Gas s distribution system. ... 

Ogden says that as a rough measure, 1 million scf per day fuels about 800 PEM-fuel-cell cars each day, or about 80 PEM-fuel-cell buses. 

PEM fuel cells are used primarily for transportation applications and some stationary applications. Due to their fast start-up time, low sensitivity to orientation, and favourable power-to-weight ratio, PEM fuel cells are particularly suitable for use in passenger vehicles, such as cars and buses. 

Freedom CAR partnership between USDOE, General Motors, Ford and DaimlerChrysler to develop PEM fuel cells for use in automotive applications. 

As with the technologies considered earlier, the main deterrent is cost. Today s fuel cell demonstration cars and buses are custom-made prototypes that cost about 1 million apiece.41 Economies of scale in mass manufacture would bring this cost to a more reasonable 6,000-10,000 range. This translates to about 125 per kilowatt of engine power, which is about four times as high as the 30 per kilowatt cost of a comparable gasoline-powered internal combustion engine.41 A major cost component in the PEM fuel cell is the noble metal (usually Pt) electrocatalyst. Efforts are underway in many laboratories to find less expensive substitutes (see for example, Refs. 42-44). 

Durability is a fundamental and necessary feature for PEM fuel cells to see a wide diffusion as a practical power source in any application field. The requirements for fuel cell lifetime vary with the specific application, in particular a duration of at least 5000 h is mandatory for use on cars, while even longer periods are needed for bus and stationary employments (for most applications an acceptable degradation rate is considered to be comprised in the range 2-10 pV/h [51]). However, the wide variability of operative conditions usually encountered in automotive applications, such as dynamic driving cycles, startup/shutdown phases, and freeze/thaw, makes also the target for car very difficult to be met with the current technologies. 

At the Detroit Auto Show, the Chrysler Corporation unveiled the mockup of a PEM-fuel-cell passenger car that would be fueled by hydrogen extracted from gasoline or other liquid hydrocarbon fuel by an onboard processor developed by Arthur D. Little, Inc. 

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