Transportation and Climate
Tools, Analysis, and Publications
NOTE: You will need Adobe Acrobat Reader, available as a free download, to view some of the files on this page. See EPA's PDF page to learn more about PDF, and for a link to the free Acrobat Reader.
This page provides information about measuring greenhouse gas emissions from transportation, the contribution of transportation sources to total emissions of greenhouse gases, and solutions for reducing emissions from transportation.
- Measuring Greenhouse Gas Emissions from Transportation
- Optimization Model for Reducing Emissions of Greenhouse Gases from Automobiles (OMEGA)
- Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) Tool
- Fact Sheets
- Technical Reports
- Transportation Solutions
Optimization Model for Reducing Emissions of Greenhouse Gases from Automobiles (OMEGA) which estimates the technology cost for automobile manufacturers to achieve variable fleet-wide levels of vehicle greenhouse gas emissions.
Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) Tool is a physics-based full vehicle simulation tool which estimates the greenhouse gas emissions for various vehicle types and powertrain technologies running over user-defined driving cycles.
The following fact sheet addresses common questions about greenhouse gas emissions from passenger vehicles and how these emissions are measured and calculated.
- Greenhouse Gas Emissions from a Typical Passenger Vehicle (PDF) (5 pp, 167K, EPA-420-F-11-041, December 2011)
- Greenhouse Gas Emissions from the U.S. Transportation Sector:1990-2003 Information to help transportation agencies, the transportation industry, researchers, and the public better understand the connection between transportation and greenhouse gas emissions in the United States.
- Update of Methane and Nitrous Oxide Emission Factors for On-Highway Vehicles (PDF) (39 pp, 683K, EPA420-P-04-016, November 2004) Report on Methane and Nitrous Oxide Emission Factors for use in the development of the mobile source emissions factor model MOVES.
Approaches for reducing greenhouse gases from transportation include using low greenhouse gas fuels, improving vehicle technologies, and reducing the number of vehicle miles traveled. In combination, these strategies can reduce transportation-related emissions significantly.
For information on system approaches to reducing greenhouse gas emissions and petroleum consumption that combine technology, fuels, and travel demand management, see:
- Full Report: A Wedge Analysis of the U.S. Transportation Sector (PDF) (23 pp, 535K, EPA420-R-07-007, April 2007) A study of the U.S. transportation sector that provides an integrative analysis of system approaches.
- Fact Sheet: A Wedge Analysis of the U.S. Transportation Sector (PDF) (6 pp, 1.6M, EPA420-F-07-049, October 2007)
For information on the reductions that the U.S. transportation sector could achieve in greenhouse gas emissions and oil consumption, as requested by Senator Kerry, see:
- Cover Letter from EPA to the Office of Senator John Kerry (PDF) (1 pp, 1.1MB, February 10, 2010)
- EPA Analysis of the Transportation Sector: Greenhouse Gas and Oil Reduction Scenarios (PDF) (56 pp, 564K, February 10, 2010)
Alternative Fuels and Renewable Fuels pages provide information on the use of environmentally beneficial alternative fuels and vehicles, including information about fuels such as E85 ethanol, biodiesel, and others. For more information, see:
- E85, Ethanol and Flex Fuel Vehicles (PDF) (3 page, 117K, EPA-420-F-10-010, February 2010)
- Biodiesel (PDF) (3 pages, 90K, EPA-420-F-10-009, February 2010)
For information on EPA's analysis of lifecycle greenhouse gas emissions from increased renewable fuels use, conducted as part of revisions to the National Renewable Fuel Standard program, please see: EPA Lifecycle Analysis of Greenhouse Gas Emissions from Renewable Fuels (PDF) (4 pp, 133K, EPA-420-F-10-006, February 2010)
For information on vehicle technologies that can lower greenhouse gas emissions and save on fuel costs, see:
EPA’s SmartWay Transport Partnership is an innovative collaboration between EPA and the freight sector designed to improve transport energy efficiency, reduce greenhouse gas and air pollutant emissions, and improve energy security. SmartWay Transport promotes a wide array of strategies to reduce the environmental impacts of moving America's goods, including technology solutions and simple behavior and policy changes that make a big difference.
- Plug-in hybrid vehicles (PDF) (2 pp, 89K, EPA420-F-07-048, October 2007)
- Electric Vehicles (PDF) (2 pp, 68K, EPA420-F-00-034, March 2002)
- Hydrogen and Fuel Cells
- Non-GHG Air Quality Modeling
- Air Quality Modeling Technical Support Document: 2017-2025 Light-Duty Vehicle Greenhouse Gas Emission Standards Final Rule (PDF) (153 pp, 10MB, EPA-454-R-12-004, August 2012)
- Emissions Inventory for Air Quality Modeling Technical Support Document 2017-2025 Light-Duty Vehicle Greenhouse Gas Final Rule (PDF) (59 pp, 2.05MB, EPA-454-R-12-005, August 2012)
- Consumer Vehicle Choice Model
- Consumer Vehicle Choice Model Documentation (PDF) (62 pp, 702K, EPA-420-B-12-052, August 2012)
- Peer Review for the Consumer Vehicle Choice Model and Documentation (PDF) (134 pp, 1.1MB, EPA-420-R-12-013, August 2012)
- Mass Reduction
- Light Duty Vehicle Mass Reduction and Cost Analysis - Midsize Crossover Utility Vehicle (FEV report) (PDF) (xx pp, xxMB, EPA-420-x-12-0xx, August 2012)
- Peer Review of Light-Duty Vehicle Mass-Reduction and Cost Analysis — Midsize Crossover Utility Vehicle (FEV Report) (PDF) (1079 pp, 35.26MB, EPA-420-R-12-019, August 2012)
- Demonstrating the Safety and Crashworthiness of a 2020 Model Year Mass Reduced Crossover Vehicle (Lotus Phase 2 Report) (PDF) (xx pp, xxk, August 2012)
- Peer Review of Demonstrating the Safety and Crashworthiness of a 2020 Model Year Mass Reduced Crossover Vehicle (Lotus Phase 2 Report) (PDF) (xx pp, xxk, August 2012)
- Supporting LS DYNA models (baseline and light weighted) (ZIP) (xxMB, August 2012)
- Assessment of NHTSA’s Report “Relationships Between Fatality Risk, Mass, and Footprint in Model Year 2000-2007 Passenger Cars and LTVs” (LBNL Phase 1 Report) (PDF) (109 pp, 2.45MB, August 2012)
- An Analysis of the Relationship between Casualty Risk Per Crash and Vehicle Mass and Footprint for Model Year 2000-2007 Light-Duty Vehicles (LBNL Phase 2 Report) (PDF) (95 pp, 2.14MB, August 2012)
- Peer Review of LBNL Statistical Analysis of the Effect of Vehicle Mass & Footprint Reduction on Safety (LBNL Phase 1 and 2 Reports) (PDF) (230 pp, 7.6MB, EPA-420-R-12-020, August 2012)
- Peer Review of the Draft Report “Modeling the Cost and Performance of Lithium-Ion Batteries for Electric-Drive Vehicles”: Revised Final Report (PDF) (96 pp, 1.02MB, EPA-420-R-12-021, August 2012)
- ANL BatPaC Model (Argonne National Laboratory Battery Performance and Cost Model v2 Beta) (EXCEL) (X.XMB, August 2012)
- Response to Peer Review for ANL Battery Pack Model (ZIP) (X.XMB, August 2012)
- Peer Review for ANL Battery Pack Model (ZIP) (X.XMB, August 2012)
- Light-Duty Automotive Technology and Fuel Economy Trends: 1975 Through 2011
- This report provides data on the fuel economy and technology characteristics of new light-duty vehicles (cars, vans, sport utility vehicles (SUVs), and pickup trucks) for model years 1975 through 2011.
- Ricardo Computer Simulation of Light-Duty Vehicle Technologies for Greenhouse Gas Emission Reduction in the 2020-2025 Timeframe (PDF) (150 pp, 3.78MB, EPA-420-R-11-020, December 2011)
- Response to Peer Review of: Ricardo Computer Simulation of Light-Duty Vehicle Technologies for Greenhouse Gas Emission Reduction in the 2020-2025 Timeframe (PDF) (434 pp, 8.59MB, EPA-420-R-11-020, December 2011)
- Ricardo Response Surface Model Tool (zip) (7.85MB, January 2012)
- Light-Duty Technology Cost Analysis Pilot Study (PDF) (317 pp, 5.8M, EPA420-F-09-020 December 2009)
- Supporting Excel spreadsheets can be found in the Electronic Docket at regulations.gov; search for "EPA-HQ-OAR-2009-0472-11395," and see the documents with IDs EPA-HQ-OAR-2009-0472-11395.1 through EPA-HQ-OAR-2009-0472-11395.23
- ICF International Pilot Study Peer Review Report (PDF) (135 pp, 742K, December 2009)
- EPA Pilot Study Peer Review - Response to Comments (PDF) (26 pp, 187K, EPA420-F-09-021, December 2009)
- Report on Additional Case Studies (PDF) (184 pp, 2.1MB, EPA420-R-10-010, April 2010)
- Supporting Excel spreadsheets can be found in the Electronic Docket at regulations.gov; search for "EPA-HQ-OAR-2009-0472-11604," and see the documents with IDs EPA-HQ-OAR-2009-0472-11604.1 through EPA-HQ-OAR-2009-0472-11604.77
- EPA Staff Technical Report: Cost and Effectiveness Estimates of Technologies Used to Reduce Light-Duty Vehicle Carbon Dioxide Emissions (PDF) (82 pp, 883K, EPA420-F-08-008, March 2008)
- Light-Duty Technology Cost Analysis, Power-Split and P2 HEV Case Studies (PDF) (153 pp, 8.7M, EPA-420-R-11-015, November 2011)
- Peer Review of FEV Inc. Report "Light-Duty Technology Cost Analysis, Power-Split and P2 HEV Case Studies (PDF) (88 pp, 784K, EPA-420-R-11-016, November 2011)
- Light-Duty Technology Cost Analysis, Power-Split and P2 HEV Case Studies - Response to Peer Reviewer Comments (PDF) (19 pp, 137K, EPA-420-R-11-017, November 2011)
- Light-Duty Vehicle Technology Cost Analysis, Advanced 8-Speed Transmissions (PDF) (29 pp, 615K, EPA-420-R-11-022, November 2011)
- Light-Duty Vehicle Technology Cost Analysis, Mild Hybrid and Valvetrain Technology (PDF) (91 pp, 2.5MB, EPA-420-R-11-023, November 2011)
- Potential Stranded Capital Analysis on EPA Light-Duty Technology Cost Analysis (PDF) (21 pp, 142K, EPA-420-R-11-019, November 2011)
- Report: A Study of Potential Effectiveness of Carbon Dioxide Reducing Vehicle Technologies. This report, prepared for EPA by the engineering firm Ricardo under subcontract to Perrin Quarles Associates, Inc., provides a detailed assessment of the carbon dioxide emissions reduction potential of a large number of conventional vehicle technology packages. Also included is a peer review of the report, as well as a presentation given by EPA to the National Research Council's Committee on Fuel Economy of Light-Duty Vehicles, which provides contextual background for this report.
- Revised Full Report (PDF) (126 pp, 4.7M, EPA420-R-08-004a, June 2008)
- Peer Review (PDF) (34 pp, 317K, EPA420-S-08-002, January 2008)
- Presentation to NRC Committee regarding the Report (PDF) (13 pp, 54K)
- New Powertrain Technologies and Their Projected Costs (Interim Report), Executive Summary (PDF) (7 pp, 130K, EPA420-S-05-013, October 2005) and Full report (PDF) (81 pp, 900K, EPA420-R-05-012, October 2005)
- An interim report that projects the cost effectiveness, from a consumer perspective, of four technology strategies capable of improving new personal vehicle fuel economy over the next decade: packages of individual gasoline vehicle technologies, advanced diesel engines, gasoline electric hybrids, and diesel electric hybrids.
- Clean Automotive Technology
- EPA's research in advanced technologies for reducing emissions and improving fuel efficiency in vehicles.
- The National Vehicle and Fuel Emissions Laboratory
- EPA's National Vehicle and Fuel Emissions Laboratory conducts research on clean automotive technology and works to develop national regulatory programs to reduce air pollution from light-duty cars and trucks, heavy-duty trucks and buses, nonroad engines and vehicles, and their fuels.
- Research and Technical Reports:
For information on policies and strategies that encourage reductions in vehicle miles traveled, see: