Hydrogen fuel cell vehicles are one promising vehicle technology for reducing the long-term environmental and energy-use impacts of personal vehicle use. Depending on how the hydrogen is produced, these vehicles can have very low emissions of air pollutants and greenhouse gases while also avoiding the use of petroleum. This paper reports the findings of real-world research conducted by the Univ...

Mobile sources are among the largest contributors of four hazardous air pollutants--benzene, 1,3-butadiene, acetaldehyde, and formaldehyde--in urban areas. At the same time, federal and state governments are promoting the use of alternative fuel vehicles as a means to curb local air pollution. As yet, the impact of this movement toward alternative fuels with respect to toxic emissions has not b...

Traffic congestion is a major issue in the modern society, and unfortunately, it continues to worsen as the number of cars on the road grows behind the ability of existing road infrastructures to cope. Additionally, vehicle fuel consumption and gas emissions are increasing, and concentrated efforts to propose solutions to reduce these and consequently the pollution are needed. In this context, ...

Biogenic sources contribute a large portion of emissions of volatile organic compounds (VOCs), a precursor to tropospheric ozone (O3). These emissions are difficult to control and are affected by land-use and climate. A sensitivity analysis was performed using an emissions scenario with a 100% increase in biogenic emissions and another scenario with an additional 100% increase in motor vehicle ...

Notice This document is disseminated under the sponsorship of the Department of Transportation in the interest of information exchange. The United States Government assumes no liability for its contents or use thereof. Emissions Management Using ITS Technology report summarizes and interprets the results of three Intelligent Transportation Systems (ITS) Field Operational Tests (FOTs) that evalu...

NOTICE This Technical Report does not necessarily represent final EPA decisions or positions. It is intended to present technical analysis of issues using data that are currently available. The purpose in the release of such reports is to facilitate an exchange of technical information and to inform the public of technical developments. Executive Summary This study proposes a modeling methodolo...

Commercial transportation fuels are complex mixtures containing hundreds or thousands of chemical components, whose composition has evolved considerably during the past 100 years. In conjunction with concurrent engine advancements, automotive fuel composition has been fine-tuned to balance efficiency and power demands while minimizing emissions. Pollutant emissions from internal combustion engi...

Evaluating technology options to mitigate the climate impacts of road transportation can be challenging, particularly when they involve a tradeoff between long-lived emissions (e.g., carbon dioxide) and short-lived emissions (e.g., methane or black carbon). Here we present trends in short- and long-lived emissions for light- and heavy-duty transport globally and in the U.S., EU, and China over ...