Cars and Buses

The targets for PEMFC cars are listed in Table 8.3. One of the difficult targets to achieve appears to be the low-temperature unassisted startup at -30°C. Obviously, graphite plates cannot be used due to their high thermal capacity and mass. The plates have to be made with thin metallic materials with sufficient corrosion protection. For assisted startup at -40°C, an easy and effective way to keep the stack temperature higher should be determined. 

Technical Targets for 80 kW Fuel Cell Systems for Automotive Applications 

Cold startup time to 50% of rated power from 20°C s 10 5/5 

Source Adapted from US DOE, Fuel Cell Techrwhgies Program Technical Plan—Fuel Cells, updated in March 2011, http //wwwl.eere.energy.gov/hydrogenandfuelcells/ mypp/ pdfs/ fuel cells.pdf. 

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At the time it was diagnosed as motion sickness, but in fact it was not motion sickness. He couldn t stand the smell of gas. Our cars and buses bum diesel, and no one cares about the amount of emissions. There are black clouds of exhaust fumes everywhere. 

Cars and buses are fuelled by a volatile mixture of hydrocarbons. The mixture is called petrol in the UK, and gas (short for gasoline) in the USA. One of the main chemicals in petrol is octane, albeit in several isomeric forms. In the internal combustion engine, the carburettor first vaporizes the petrol to form an aerosol (see Section 10.2) comprising tiny droplets of petrol suspended in air (Figure 8.3). This vaporization process is similar to that which converts liquid perfume into a fine spray. 

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. 

Suggestions for concrete measures are hampered by the lack of precise data on the share of different sources. Nevertheless it can be stated that the use of private cars has strongly increased in recent years, the share of bicycles is rather low and the vehicle fleet is aged. Therefore, as a first step, datasets should be improved with respect to emissions, the share of different sources and activity data (especially private cars and buses as well as industry and domestic heating). Based on these data, actions should be implemented to address the main source categories. 

Fuel cells can also be used for other purposes. Think about the energy used by a car or other transportation vehicles. Fuel cells could be an excellent source of electrical energy for the cars and buses of the future. In fact, some researchers think that if hydrogen fuel cell-powered vehicles become common, they will cost less than half of what gasoline powered-vehicles cost today. Hydrogen fuel cell vehicles will also be easier to take care of because there will be fewer parts to repair or replace. 

It is a warm summer weekend, so you decide to visit a national park. It is nice to be away from all that pollution. But are you bringing the pollution with you Take a look at Figure 12.18. How did these campers get to the park Cars and buses release gaseous pollution into the air. On the other hand, what would it be like to live without vehicles Can we compromise in a way that protects the environment while maintaining a reasonable standard of living ... 

Conduct Fleet Demonstrations. The CaFCP will facilitate members placement of up to 300 fuel cell cars and buses in independent, fleet demonstration projects within the state during this phase. CaFCP members plan to focus these vehicles primarily in two main areas—the greater Los Angeles region, and the Sacramento-San Francisco area. 

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). 

The process by which the atoms of one or more substances are rearranged to form different substances is called a chemical reaction. A chemical reaction is another name for a chemical change, which you read about in Chapter 3. Chemical reactions affect every part of your life. They break down your food, producing the energy you need to live. They produce natural fibers such as cotton and wool in the bodies of plants and animals. In factories, they produce synthetic fibers such as nylon and polyesters. Chemical reactions in the engines of cars and buses provide the energy to power the vehicles. 

Human noses do need to tire imagine walking off the busy street into a chemist s shop. One would immediately detect the odour of the perfumes, fragranced toiletries and other goods, but the outside smells would be very much in the background. However, an instrument just inside the door would still be picking up the exhaust and diesel fumes of the passing cars and buses. In many applications of an ideal artificial nose, this needs to be catered for. Currently, the only answer is to ensure no extraneous odours or non-odorants enter the machine. 

The first test runs of an experimental liquid-hydrogen refueling device for cars and buses began at Solar-Wasserstoff-Bayern s prototype solar hydrogen plant in Bavaria. The goal was to refuel a car in a few minutes. 

Daimler-Benz and Canada s Ballard Power Systems began a cooperative effort to develop fuel cells for cars and buses. 

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