Transportation's Role in Reducing U.S. Greenhouse Gas Emissions: Volume 1: Synthesis Report and Volume 2: Technical Report

This study evaluates potentially viable strategies to reduce transportation greenhouse gas (GHG) emissions. The study was mandated by the Energy Independence and Security Act (P.L. 110-140, December 2007). The Act directed the U.S. Department of Transportation (DOT), in coordination with the U.S. Environmental Protection Agency (EPA) and consultation with the U.S. Global Change Research Program (USGCRP), to conduct a study of the impact of the Nation’s transportation system on climate change and strategies to mitigate the effects of climate change by reducing GHG emissions from transportation. This study also examines the potential impact of these strategies on air quality, petroleum savings, transportation goals, costs, and other factors. Each GHG reduction strategy may have various positive impacts (including co-benefits) or negative impacts on these factors. Potential tradeoffs and interdependencies when reducing GHG emissions will need to be considered in order to develop balanced solutions. This study does not take a position as to which strategy, or collection of strategies, should be adopted to accomplish the Nation’s clean energy and GHG reduction goals. Rather, the study attempts to objectively examine numerous proposed strategies and assess their potential to reduce transportation GHG emissions. The assessments are based on published scientific literature, current policy studies, and best professional estimates. Each strategy is assessed relative to projections of future transportation GHG emissions based on U.S. Energy Information Administration Annual Energy Outlook (AEO) estimates. The study is presented in two parts: Volumes 1 and 2. Volume 1: Synthesis Report provides an overview of the study’s findings and discusses policy options that Congress may wish to consider to reduce transportation GHG emissions. Volume 2: Technical Report provides the technical details of the assessment.