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Regulations for Emissions from Vehicles and Engines

Midterm Evaluation of Light-Duty Vehicle Greenhouse Gas Emissions Standards for Model Years 2022-2025

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Overview

As part of the 2012 rulemaking establishing the model year (MY) 2017-2025 light-duty vehicle greenhouse gas (GHG) standards, EPA made a regulatory commitment to conduct a Midterm Evaluation (MTE) of the standards for MY 2022-2025. As a part of this process, EPA examed a wide range of factors, such as developments in powertrain technology, vehicle electrification, light-weighting and vehicle safety impacts, the penetration of fuel efficient technologies in the marketplace, consumer acceptance of fuel efficient technologies, trends in fuel prices and the vehicle fleet, employment impacts, and many others.

EPA’s regulations require several formal steps in the MTE process, including opportunities for public input.

  • Step 1: Draft Technical Assessment Report (TAR) issued jointly with the National Highway Traffic Safety Administration (NHTSA) and the California Air Resources Board (CARB) with opportunity for public comment. (July 2016)
  • Step 2: The Former EPA Administrator made a Proposed Determination with opportunity for public comment. (November 2016) (This step was reevaluated under the direction of former EPA Administrator Scott Pruitt)  
  • Step 3: The EPA Administrator must make a final determination with regard to whether the standards remain appropriate or should be changed by April 1, 2018.   

Mid-term Evaluation Final Determination

On April 2, 2018, the Administrator signed the Mid-term Evaluation Final Determination which finds that the model year 2022-2025 greenhouse gas standards are not appropriate in light of the record before EPA and, therefore, should be revised. The Federal Register Notice announcing the Administrator’s decision is available for review below.

Federal Register Notice: Mid-term Evaluation of Greenhouse Gas Emissions Standards for Model Year 2022-2025 Light-duty Vehicles (PDF) (11 pp, 634 K, published April 13, 2018, About PDF)

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The Mid-term Evaluation Process

Reconsideration of the Midterm Evaluation Final Determination

On March 15, 2017, former EPA Administrator Scott Pruitt and Department of Transportation Secretary Elaine Chao announced that EPA intended to reconsider the final determination, issued on January 12, 2017, that recommended no change to the greenhouse gas standards for light duty vehicles for model years 2022- 2025. EPA announced it woud reconsider that determination in coordination with NHTSA.

The Mid-term Evaluation process was established as a part of the 2012 final GHG emissions standards for model years 2017-2025, requiring EPA to determine no later than April 1, 2018, whether the standards  for model years 2022-2025 established are appropriate. In accord with this schedule, EPA announced that it intended to make a new Final Determination regarding the appropriateness of the standards no later than April 1, 2018. 

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Previous Steps in the Midterm Evaluation Process

On January 12, 2017, Administrator Gina McCarthy signed her determination to maintain the current GHG emissions standards for model year (MY) 2022-2025 vehicles. Her final determination found that automakers are well positioned to meet the standards at lower costs than previously estimated. 

Highlights of Administrator McCarthy's January 2017 Final Determination

  • Automakers have a wide range of technology pathways available to meet the MY2022-2025 standards, at slightly lower per-vehicle costs than previously predicted. The standards are achievable with very low penetration of strong hybrids, electric vehicles and plug-in hybrid electric vehicles, consistent with the findings of a comprehensive 2015 National Academy of Sciences study.
  • The standards will save consumers money, significantly reduce GHG emissions and fuel consumption, and provide benefits to the health and welfare of Americans.
  • Automakers have outperformed the standards for the first four years of the program (MY2012-2015) and manufacturers are adopting fuel efficient technologies at unprecedented rates, all while vehicle sales have increased for 7 consecutive years.

Administrator McCarty's determination was based on an extensive technical record, created over 8 years of research, review of several hundred published reports, hundreds of stakeholder meetings, and multiple opportunities for the public to provide input. This Final Determination follows the November 2016 release of EPA’s Proposed Determination and the July 2016 release of a Draft Technical Assessment Report (TAR), issued jointly by the EPA, the National Highway Traffic Safety Administration (NHTSA), and the California Air Resources Board (CARB). EPA provided opportunities for public comment for both the Draft TAR and the Proposed Determination.

Cover Letter -- EPA Administrator’s signed Cover Letter to the Final Determination.

Final Determination Document -- Final Determination on the Appropriateness of the Model Year 2022-2025 Light-duty Vehicle Greenhouse Gas Emissions Standards under the Midterm Evaluation (PDF)(33 pp, 560 K, January 2017, EPA-420-R-17-001).

Response to Comments Document -- Final Determination on the Appropriateness of the Model Year 2022-2025 Light-duty Vehicle Greenhouse Gas Emissions Standards under the Midterm Evaluation: Response to Comments (PDF)(174 pp, 1.58 MB, January 2017, EPA-420-R-17-002).

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Proposed Determination

On November 30, 2016,  Administrator McCarthy  proposed to determine that the MY 2022-2025 standards remain appropriate and that a rulemaking to change them is not warranted. This proposed determination was based on the robust technical record including the draft TAR, input from the auto industry and other stakeholders, and updated analyses. The public comment period for this proposed determination ended on December 30, 2016.

Highlights of the Proposed Determination

  • Auto manufacturers can meet the MY 2022-2025 standards at slightly lower per-vehicle costs than predicted in the TAR, and lower costs than predicted in the 2012 rulemaking that established the standards.
  • The current standards will save consumers money and provide benefits to the health and welfare of Americans.
  • Automakers have a wide range of technology pathways available to meet the standards. Standards are achievable with very low penetration of strong hybrids, electric vehicles and plug-in hybrid electric vehicles. This finding is consistent with the conclusions the National Academy of Sciences found in a comprehensive 2015 study.
  • Automakers have outperformed the standards for the first four years of the program (MY2012-2015) and manufacturers are adopting fuel efficient technologies at unprecedented rates, all while vehicle sales have increased for 6 consecutive years. There are over 100 car, SUV, and pickup versions on the market today that already meet 2020 or later standards.

Cover Letter –- EPA Administrator’s signed Cover Letter to the Proposed Determination.

Proposed Determination Document -- Proposed Determination on the Appropriateness of the Model Year 2022-2025 Light-duty Vehicle Greenhouse Gas Emissions Standards under the Midterm Evaluation (PDF) (268 pp, 6.38 MB, EPA-420-R-16-020, November 2016)

Technical Support Document to the Proposed Determination -- Proposed Determination on the Appropriateness of the Model Year 2022-2025 Light-duty Vehicle Greenhouse Gas Emissions Standards under the Midterm Evaluation: Technical Support Document (PDF)(719 pp, 18 MB, EPA-420-R-16-021, November 2016)

Notice of Availability of a Proposed Order: Proposed Determination on the Appropriateness of the Model Year 2022-2025 Light-duty Vehicle Greenhouse Gas Emissions Standards under the Midterm Evaluation (PDF) (2 pp, 199 K, published December 6, 2016)

For additional documents supporting EPA’s analyses for the Proposed Determination, see the Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) Tool and the Optimization Model for reducing Emissions of Greenhouse gases from Automobiles (OMEGA) pages.

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Draft Technical Assessment Report (TAR)

EPA, NHTSA, and CARB jointly issued a Draft TAR for public comment in July 2016. The Draft TAR was a technical report, not a decision document, and examined a wide range of issues relevant to the 2022-2025 standards.

Highlights of the Draft Technical Assessment Report:

For additional documents supporting EPA’s analyses for the Proposed Determination, see the Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) Tool and the Optimization Model for reducing Emissions of Greenhouse gases from Automobiles (OMEGA) pages.

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EPA Technical Projects to Inform the Midterm Evaluation

In addition to these projects supporting the MTE, EPA issues two annual reports related to light-duty GHG emissions:

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EPA Publications Informing the Midterm Evaluation

Throughout the MTE process, EPA’s goal was to publish as much of our research as possible in peer-reviewed journals. EPA staff have published the following peer-reviewed papers so far since 2013. EPA staff attended numerous technical conferences, and assessed hundreds of papers in the literature on the wide range of factors considered for the MTE.

The following papers are not available for download due to copyright restrictions; however, we are providing links to the abstract and ordering information on the journals’ websites.

The following links exit the site Exit

The following papers are not subject to copyright protection because they are Government works; however, foreign copyrights may apply. 

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EPA Presentations Regarding the Midterm Evaluation

EPA also has publicly presented information about our work in numerous forums.

Click the links below to view selected presentations:

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