ASSESSMENT OF TECHNOLOGIES FOR
Improving Light-Duty Vehicle
Committee on Assessment of Technologies for Improving Fuel Economy
of Light-Duty Vehicles—Phase 3
Board on Energy and Environmental Systems
Division on Engineering and Physical Sciences
A Consensus Study Report of
THE NATIONAL ACADEMIES PRESS
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This activity was supported by Award No. DTNH2217H00028 of the U.S. Department of Transportation and National Highway Traffic Safety Administration. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.
International Standard Book Number-13: 978-0-309-37122-3
International Standard Book Number-10: 0-309-37122-8
Digital Object Identifier: https://doi.org/10.17226/26092
Library of Congress Control Number: 2021951949
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2021. Assessment of Technologies for Improving Light-Duty Vehicle Fuel Economy—2025–2035. Washington, DC: The National Academies Press. https://doi.org/10.17226/26092.
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COMMITTEE ON ASSESSMENT OF TECHNOLOGIES FOR IMPROVING FUEL ECONOMY OF LIGHT-DUTY VEHICLES—PHASE 3
GARY MARCHANT, Arizona State University, Chair
CARLA BAILO, Center for Automotive Research
RODICA BARANESCU, NAE,1 University of Illinois, Chicago (retired) (resigned September 2020)
NADY BOULES, NB Motors, LLC
DAVID L. GREENE, University of Tennessee, Knoxville (resigned March 2021)
DANIEL KAPP, D.R. Kapp Consulting, LLC
ULRICH KRANZ, Canoo
THERESE LANGER, American Council for an Energy-Efficient Economy
ZHENHONG LIN, Oak Ridge National Laboratory
JOSHUA LINN, University of Maryland, College Park
NIC LUTSEY, International Council on Clean Transportation
JOANN MILLIKEN, Independent Consultant, Alexandria, Virginia
RANDA RADWAN, Highway Safety Research Center, University of North Carolina, Chapel Hill
ANNA STEFANOPOULOU, University of Michigan and Automotive Research Center
DEIDRE STRAND, Wildcat Discovery Technologies
KATE WHITEFOOT, Carnegie Mellon University
ELIZABETH ZEITLER, Associate Director, Board on Energy and Environmental Systems (BEES), Study Director
REBECCA DeBOER, Research Assistant, BEES
BRENT HEARD, Associate Program Officer, BEES (beginning January 2020)
K. JOHN HOLMES, Director/Scholar, BEES
MICHAELA KERXHALLI-KLEINFIELD, Research Associate, BEES
KASIA KORNECKI, Associate Program Officer, BEES (beginning February 2020)
KATHERINE KORTUM, Senior Program Officer, Transportation Research Board
HEATHER LOZOWSKI, Senior Financial Business Partner, BEES
BEN WENDER, Senior Program Officer, BEES (until December 2019)
CATHERINE WISE, Associate Program Officer, BEES (beginning June 2020)
NOTE: See Appendix B, Disclosure of Conflicts of Interest.
1 Member, National Academy of Engineering.
BOARD ON ENERGY AND ENVIRONMENTAL SYSTEMS
JARED COHON, NAE,1 Carnegie Mellon University, Chair
VICKY BAILEY, Anderson Stratton Enterprises
CARLA BAILO, Center for Automotive Research
W. TERRY BOSTON, NAE, GridLiance GP, LLC, and Grid Protection Alliance
DEEPAKRAJ DIVAN, NAE, Georgia Institute of Technology
MARCIUS EXTAVOUR, XPRIZE
KELLY SIMS GALLAGHER, Tufts University
TJ GLAUTHIER, TJG Energy Associates, LLC
NAT GOLDHABER, Claremont Creek Ventures
DENISE GRAY, LG Chem Michigan, Inc.
JOHN KASSAKIAN, NAE, Massachusetts Institute of Technology
BARBARA KATES-GARNICK, Tufts University
DOROTHY ROBYN, Boston University
JOSÉ SANTIESTEBAN, NAE, ExxonMobil Research and Engineering Company
ALEXANDER SLOCUM, NAE, Massachusetts Institute of Technology
JOHN WALL, NAE, Cummins, Inc. (retired)
ROBERT WEISENMILLER, California Energy Commission (former)
K. JOHN HOLMES, Director/Scholar
ELIZABETH ZEITLER, Associate Director
HEATHER LOZOWSKI, Senior Financial Business Partner
BEN WENDER, Senior Program Officer (until December 2019)
BRENT HEARD, Associate Program Officer (beginning January 2020)
KASIA KORNECKI, Associate Program Officer (beginning February 2020)
CATHERINE WISE, Associate Program Officer (beginning June 2020)
MICHAELA KERXHALLI-KLEINFIELD, Research Associate
REBECCA DeBOER, Research Assistant
1 Member, National Academy of Engineering.
Passenger car and truck manufacturers have faced corporate average fuel economy standards since 1978 and greenhouse gas emissions standards since 2012, governed by several statutes and specified in regulations from the U.S. Department of Transportation’s National Highway Traffic Safety Administration (NHTSA) and the U.S. Environmental Protection Agency (EPA). Over this period, vehicle efficiency technology has advanced dramatically, including improvements to internal combustion engine powertrains; introductions of efficient hybrid, electric, and fuel cell vehicles; improvements to vehicle aerodynamics and mass reduction technologies; and introduction of limited vehicle automation. NHTSA and EPA have increasingly incorporated technology analysis into estimate costs and benefits of fuel economy and greenhouse gas standards. Beginning in 2007, Congress requested that the National Academies of Sciences, Engineering, and Medicine undertake periodic review of technologies for fuel economy standards. Most recently, NHTSA contracted with the National Academies to form the Committee on Assessment of Technologies for Improving Fuel Economy of Light-Duty Vehicles—Phase 3 to update the requested technology, consumer behavior, and policy analysis of vehicle efficiency technologies for 2025–2035.
The committee was asked to assess technologies for improving the fuel economy of light-duty vehicles in 2025–2035 and to provide updated estimates of the potential cost, fuel economy improvements, and barriers to deployment of these technologies. The committee was asked to consider internal combustion engine, electric, and fuel cell propulsion systems; non-powertrain technologies; the structure of the fuel economy regulations related to new technologies; shifts in personal transportation and vehicle ownership models; and consumer behavior associated with new efficiency technologies.
The committee comprised a wide array of backgrounds and sought input from agency officials, vehicle manufacturers, equipment suppliers, consultants, nongovernmental organizations, academicians, and many other experts. In addition to regular committee meetings, committee members held webinars on several critical topics, spoke in public sessions with experts in state and federal government, and conducted numerous information-gathering site visits to automobile manufacturers and suppliers. The committee put great effort into thorough preparation for these meetings, asked probing questions, and requested follow-up information in order to understand the perspectives of the many stakeholders. In addition, the committee commissioned a material substitution and mass reduction study from the Center for Automotive Research in order to better understand the opportunities for these advances. I greatly appreciate the considerable time and effort contributed by the committee’s individual members throughout our information-gathering process, report writing, and deliberations, and especially for persevering through the challenges presented by the COVID-19 pandemic during the important final stages of completing our report.
The committee operated under the auspices of the National Academies Board on Energy and Environmental Systems, in collaboration with the Transportation Research Board. I would like to recognize the study staff for organizing and planning meetings, and assisting with information gathering and report development. The efforts of our hardworking and knowledgeable study director Elizabeth Zeitler, ably assisted by her National Academies colleagues Rebecca DeBoer, Michaela Kerxhalli-Kleinfield, Brent Heard, Kasia Kornecki, Catherine Wise, K. John Holmes, and Katherine Kortum, were critical to the committee’s delivery of its report. I would also like to recognize Ben Wender and Janki Patel for their early input. Thanks are also due to the many experts and presenters, too numerous to name individually, who contributed to the committee’s data-gathering process. Their contributions were invaluable and are listed in Appendix C.
Chair, Committee on Assessment of Technologies
for Improving Fuel Economy of Light-Duty Vehicles—Phase 3
Acknowledgment of Reviewers
This Consensus Study Report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.
We thank the following individuals for their review of this report:
Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report nor did they see the final draft before its release. The review of this report was overseen by Susan Hanson, Clark University, and Andrew Brown Jr., Diamond Consulting, Engineering, and Management Services. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.
1 Member, National Academy of Sciences.
2 Member, National Academy of Engineering.
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