ACCESS 34, Spring 2009

Introduction: Transportation Technologies for the 21st Century

Elizabeth Deakin

New technologies are transforming the way we plan, design, build, and operate transportation systems. Transport agencies use them to count traffic, detect crashes, collect tolls and fares, and manage transit operations and traffic signal systems. Travelers depend on traffic condition reports, electronic maps, on-board vehicle performance monitors, real-time transit arrival information, and a host of other services that did not exist a generation ago. Some of us are already driving hybrid vehicles or commuting in buses powered by hydrogen or biofuels. For the future, we all are counting on additional advances in transportation technology, not just to get us where we want to go, but also to reduce greenhouse gases, improve air quality, and support economic development.

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Saving Fuel, Reducing Emissions: Making Plug-In Hybrid Electric Vehicles Cost Effective

Daniel Kammen, Samuel Arons, Derek Lemoine, and Holmes Hummel

Cars and light trucks in the U.S. consume about eight million barrels of gasoline per day, more than total US petroleum production. They account for eighteen percent of national greenhouse gas emissions. Both motor vehicle gasoline consumption and emissions have been rising at about 1.5 percent per year. Plug-in hybrid electric vehicles (PHEVs) could alter these trends. On a vehicle technology spectrum that stretches from fossil-fuel- powered conventional vehicles through hybrid electric vehicles to all-electric vehicles, PHEVs fall between hybrids and all-electrics. They have both gas tanks and batteries, like hybrids, and can run either in gasoline-fueled mode or in electric mode. Their batteries are much larger than batteries in other hybrids, and they can store electricity directly from the grid as well as electricity derived from regenerative braking, as do conventional hybrid vehicles. PHEVs combine the best aspects of conventional vehicles (long range and easy refueling) with the best attributes of all-electric vehicles (low tailpipe emissions and reduced petroleum use). Widespread use of PHEVs could reduce transportation-related GHG emissions, improve urban air quality, reduce petroleum consumption, and expand competition in the transportation fuels sector. Several companies now offer to convert hybrid vehicles to PHEVs, and several automakers have announced PHEV development projects.

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2018-02-07T23:15:19+00:00Categories: ACCESS 34, Spring 2009|Tags: , |

Moving Forward With Fuel Economy Standards

Lee Schipper

In the early 1970s, the American Petroleum Institute had a slogan: “A nation that runs on oil can’t afford to run short.” Yet at the beginning of 1973, the US relied on oil for 46 percent of its energy supply, of which 32 percent was imported. Today we import about two thirds of the oil we consume. The price of crude oil in early 1973 was around $3 a barrel, and gasoline cost 39 cents a gallon. In 2009 dollars, those figures are close to $15 a barrel and $1.85 a gallon. Crude oil prices in early 2009 were still almost three times higher than in 1973. However, the fuel cost for driving a mile is less today than in 1973, because cars are more fuel-efficient and it takes thirty percent less fuel to go a distance today than in 1973.

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2018-02-07T23:17:15+00:00Categories: ACCESS 34, Spring 2009|Tags: , |

Transforming the Oil Industry into the Energy Industry

Daniel Sperling and Sonia Yeh

When it comes to energy security and climate change concerns, transportation is the principal culprit. It consumes half the oil used in the world and accounts for almost one fourth of all greenhouse gas (GHG) emissions. In the United States, it plays an even larger role, consuming two thirds of the oil and causing about one third of the GHG emissions in the country. Vehicles, planes, and ships remain almost entirely dependent on petroleum. Efforts to replace petroleum, usually for energy security reasons but also to reduce local air pollution, have continued episodically for years— and largely failed.

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2022-10-11T19:31:14+00:00Categories: ACCESS 34, Spring 2009|Tags: |

Intelligent Transport Systems: Linking Technology and Transport Policy to Help Steer the Future

Elizabeth Deakin, Karen Trapenberg Frick, and Alexander Skabardonis

If you’ve seen an electronic message sign along the highway that tells you how long it will take to get downtown or to the airport, or paid your toll or your parking fees with an electronic tag, or ridden a bus that triggered the traffic lights to turn green as it approached them, then you have experienced some of the benefits of Intelligent Transportation Systems (ITS)—an umbrella term for a variety of new technologies and operations methods for highways and transit. Other on-the-ground ITS applications are less visible to the average traveler, but every bit as useful: they help traffic managers detect and respond to accidents promptly, handle the extra traffic that special events generate, and help state workers safely plow snow on mountain roads in blinding snowstorms.

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2018-02-07T23:30:02+00:00Categories: ACCESS 34, Spring 2009|Tags: |