Transportation Summary

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To cope with ever-increasing problems associated with transportation, various approaches have been proposed. Among options considered are: 1) reduce vehicle use, 2) increase the efficiency and reduce the emissions of conventional gasoline-powered vehicles, 3) switch to less noxious fuels, and 4) use cleaner alternative systems. The first choice calls for developing a large-scale mass transit system, carpooling, reducing travel by working from home, and removing the need for excessive driving by implementing more effective community designs. This will also reduce much of the social costs such as traffic congestion and delays, pollution, accidents, repair costs, and other social ills such as fatigue and stress. Although this option helps with many social and environmental problems, by itself it seems to have limited success.

The second and third approaches are to make existing transportation systems better by designing more efficient cars or vehicles that use better and less-polluting fuels. Internal combustion engines have been around for a long time and their efficiencies have been greatly improved. It seems that improving efficiencies beyond current levels only comes in small steps and no major breakthrough is eminent in the near future. Alternative fuels like methanol and natural gases have been tried by a number of investigators with marginal improvements in emissions and fuel efficiencies. Hydrogen seems to be the obvious alternative fuel. Problems associated with hydrogen storage, safety concerns, and the lack of a hydrogen distribution infrastructure have been major obstacles to commercial development of hydrogen-propelled internal combustion engines, although a number of automotive manufacturers have developed prototype units.

The fourth option is to do away with current technologies in favor of newer and cleaner alternatives. In order for electric, hybrid, or any other types of cars to find mass market acceptability, they must meet certain requirements. They must have a full-size trunk, be able to travel large distances, recharge in a short time, have all the comfort and luxury of the conventional cars, and be offered at costs comparable to conventional internal combustion engines. Unless there are major breakthroughs in advanced battery technologies, it does not appear that battery-powered electric vehicles, in their current form, can make headway in achieving a major market share.28 Their uses would probably be limited to small service vehicles, fleet operation, and in areas where pollution, not driving range, is of primary concern.

When and if fuel cell cars become popular and infrastructure is in place, fuel cells will not only be cost effective, but may also be a source of income for their owners. As US data shows, Americans drive their cars only 4% of the time. The remaining 96% of the time cars sit idly in parking garages either at work or at home. During these times, cars can be used as tiny power plants, producing electricity which can be put on grids and sold to utility companies. In this way, a large fraction of the cost of owning and maintaining the cars may be recovered, and our reliance on foreign oil and other nonrenewable technologies reduced.

For now, hybrid vehicles consisting of a petrol engine and a battery-powered electric motor seem to be the preferred option. In the long term, fuel cells using pure hydrogen offer the best hope. In the meantime, petroleum-based reformers may be the solution as we transition to on-board hydrogen storage in the future.

A technological revolution is underway which makes future transportation systems even more efficient. New advanced polymer and carbon-fiber composites are developed that are lighter and safer to use. Composites can be made that design frame-less “monocoques” that cost less, are many times stronger than conventional frames, are lighter than steel by two to three times, and absorb five times more energy. This helps not only in designing safer cars, but also in reducing rolling resistance and power requirements for climbing and accelerating. The reduction in required power results in smaller engines, transmissions, and other components, which in turn makes it possible to make the vehicle even lighter.


(1) Toossi Reza, "Energy and the Environment:Sources, technologies, and impacts", Verve Publishers, 2005

Further Reading

Tillman, D., Fuels of Opportunity: Characteristics and Uses In Combustion Systems, Academic Press, 2004.

Sorensen, K., Hydrogen and Fuel Cells: Emerging Technologies and Applications, Academic Press, 2005.

Dhameia, S., Electric Vehicle Battery Systems, Academic Press, 2001.

Hussain, I., Electric and Hybrid Vehicles: Design Fundamentals, CRC Press, LLC. 2003.

Jefferson, C.M., and Barnard, R. H., Hybrid Vehicle Propulsion, WIT Press, 2002.

Spelberg, D. The Hydrogen Energy Transition: Moving Toward the Post Petroleum Age in Transportation, Academic Press, 2004.

Fuel, Direct Science Elsevier Publishing Company, Fuel focuses on primary research work in the science and technology of fuel and energy fuel science.

Transportation Research Part C: Emerging Technologies, Direct Science Elsevier Publishing Company; this journal focuses on scholarly research on development, application, and implications in the fields of transportation, control systems, and telecommunications, among others.

Fuel Cells Bulletin, Direct Science Elsevier Publishing Company, Fuel Cells Bulletin is the leading source of technical and business news for the fuel cells sector.

International Journal of Hydrogen Energy, Direct Science Elsevier Publishing Company, Quarterly journal covering various aspects of hydrogen energy, including production, storage, transmission, and utilization, as well as economical and environmental aspects.

External Links

US Department of Transportation (

US Department of Energy (

US Environmental Protection Agency (

National Energy Renewable Laboratory Hybrid Electric &Fuel Cell Vehicles (

FreedomCar (