Policy makers in transportation often make investment decisions involving hundreds of millions of dollars. Typically they evaluate a wide range of alternatives -- from expanding highway capacity to managing existing demand to building a new rail line -- with respect to a broad array of seemingly...

In this paper, we review some of the basic energy balance and climate change impact issues associated with biofuels. For both the basic energy and greenhouse gas balances of producing and using a range of fuels, and for the increasingly debated and important issues of non-greenhouse gas impacts...

This report documents the results of the first phase of a two-part project: (1) research and feasibility analysis and (2) the field operational test and research of a shared-use Segway HT, electric bicycle, and bicycle rental model linked to a Bay Area Rapid Transit (BART) District station and...

Will people recharge a vehicle that does not have to be recharged? This, and the degree to which plug-in hybrid electric vehicle (PHEV) designs emphasize gasoline or electricity, are central to assessing the energy and environmental effects of PHEVs. Plug-in conversions of hybrid vehicles are...

To help guide applications of more advanced models in policy studies, this paper presents an evaluation of model accuracy and induced demand in an integrated land use and transportation model, the 2000 Sacramento MEPLAN model. The model is currently used by the region's metropolitan planning...

Electric two-wheelers have become a significant mode of transportation in China in the past decade. Though marketed and publicized by some as zero-emission vehicles, little past research has been done to quantify the environmental impacts of electric two-wheelers in China. This paper quantifies...

With aggregate data from the U.S. Consumer Expenditure Survey for 19 years, 1984 through 2002, this study analyzes relationships between expenditures on transportation and communications. Several classification schemes for expenditure categories were used, from the most aggregate [two categories...

In this final report, we present results from research conducted under Phase I of NREL contract number XCM-4-44000-01, from May 2004-January 2005. The overall goal of this project is to better understand infrastructure development strategies for widespread implementation of hydrogen as an energy...