Various programs and initiatives are seeking ways to improve fuel efficiency and reduce emissions from existing vehicles, and to incorporate new technologies in vehicle development. Techniques for improving vehicle performance include the following:
- Alternative fuels – Many fuels or power sources derived from resources other than petroleum produce less pollution than gasoline or diesel. These include as ethanol, biodiesel, natural gas, propane, hydrogen, and electricity. The U.S. Department of Energy notes that use of alternative fuels and advanced vehicles helps to reduce vehicle emissions.
- Advanced technology vehicle – This is a vehicle that combines new engine, power, or drivetrain systems to improve fuel economy and meet specific emissions standards under the Clean Air Act. These include vehicles that use hybrid power systems and fuel cells, and some specialized electric vehicles.
- Ecodriving – This is a method of driving that improves fuel economy and reduces vehicle emissions. It includes maintaining a steady speed, shifting earlier to a higher gear, and keeping tires properly inflated. Various agencies and organizations promote ecodriving as a strategy with potential environmental and safety benefits.
- Crash avoidance features – Technologies have become available to help drivers avoid collisions. These include forward collision warning, autobrake, lane departure warning, lane departure prevention, adaptive headlights, blind spot detection, parking sensors, back-up cameras, and electronic stability control.
- Diesel bus retrofitting – Emissions from older, diesel buses can be diminished by installing devices in the exhaust system to reduce specific pollutants. Examples of retrofit devices include diesel particulate filters, diesel oxidation catalysts, selective catalytic reduction systems, and exhaust gas recirculation. Retrofits are incorporated in the U.S. EPA’s National Clean Diesel Campaign.
- Vehicle inspection and maintenance programs – These programs help improve air quality by identifying high-emitting vehicles in need of repair (through visual inspection, emissions testing, or downloading of fault codes from a vehicle's onboard computer) and requiring them to be fixed as a prerequisite to vehicle registration. More than half of states have some sort of vehicle inspection and maintenance program in place.
Such strategies can promote health through improvements to air quality. Some might also contribute to improved safety outcomes.
Related Transportation and Heath Tool Indicators
How can this strategy result in health benefits?
- Improve safety
- Reduce motor vehicle-related injuries and fatalities
- Reduce transportation's contribution to air pollution
How has this worked in practice?
The Magic School Bus Gets Cleaned Up
The U.S. EPA, in collaboration with Scholastic, created a new book in the "Magic School Bus" series for children. In "The Magic School Bus Gets Cleaned Up," students and their teacher research the pollution emitted from their diesel school bus and learn how emissions from the diesel engine can be reduced. At the end of the book, a diesel particulate matter filter is installed on the bus. U.S. EPA has also translated the book into Spanish. Scholastic operates a traveling science laboratory housed in a yellow school bus that tours the United States, visiting schools, fairs, and community events. As a part of the program, the traveling bus was retrofitted with a diesel particulate filter, reducing particulate matter by up to 90%.
Where can I learn more?
The U.S. Department of Energy Alternative Fuels Data Center provides information, data, and tools to help vehicle fleets and transportation decision makers find ways to reduce petroleum consumption through the use of alternative and renewable fuels, advanced vehicles, and other fuel-saving measures.
The U.S. DOT provides resources and information on fuel economy and air quality impacts.
The U.S. EPA Office of Transportation and Air Quality site has information about controlling emissions from passenger cars and light trucks, and from heavy-duty trucks, buses, and engines. This includes consumer information, vehicle standards and regulations, certification and compliance, inspection and maintenance, fuel economy, and test data and evaluations.
Evidence base
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Borak J, Srianni G. Studies of self-pollution in diesel school buses: Methodological issues. Journal of Occupational and Environmental Hygiene 2007;4(9):660-8.
Boriboonsomsin K, Vu A, Barth M. Eco-Driving: Pilot Evaluation of Driving Behavior Changes among U.S. Drivers. University of California Riverside, University of California Transportation Center (UCTC); 2010.
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Legal Information Institute, U.S. Code, Title 42, Chapter 152, Subchapter I, § 17013. Advanced technology vehicles manufacturing incentive program. Retrieved on July 2, 2014.
Leiby P, Rubin J. Understanding the transition to new fuels and vehicles: Lessons learned from analysis and experience of alternative fuel and hybrid vehicles. Saint Louis, MO: Elsevier Academic Press; 2004.
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U.S. Environmental Protection Agency (EPA). Devices and Additives to Improve Fuel Economy and Reduce Pollution – Do They Really Work?. Washington, DC: U.S. EPA, Office of Transportation and Air Quality; EPA-420-F-11-036; 2011.
U.S. Environmental Protection Agency (EPA). Diesel retrofit technology: An analysis of the cost-effectiveness of reducing particulate matter emissions from heavy-duty diesel engines through retrofits. Washington, DC: U.S. EPA, Office of Transportation and Air Quality; 2006.
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