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Regulations for Emissions from Vehicles and Engines

Optimization Model for reducing Emissions of Greenhouse Gases from Automobiles (OMEGA)

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Overview of OMEGA

OMEGA is a free, desktop computer application which estimates the technology cost for automobile manufacturers to achieve variable fleet-wide levels of vehicle greenhouse gas (GHG) emissions. OMEGA is designed to operate on a single computer.


OMEGA v1.4.56

(supporting the 2016 Proposed Determination and 2016 Draft Technical Assessment Report (TAR) for Model Year 2022-2025 Light-Duty Vehicle Greenhouse Gas Emissions Standards)

The downloadable installation file below contains the application executable file and five sample Microsoft Excel input files. In addition, 2 zip files contain files used to generate technology costs used as inputs to OMEGA and the OMEGA input/output files used to generate results presented in the 2016 Proposed Determination and 2016 Draft TAR. Please note that the zip file is a large download.

  • Model Documentation v1.4.56 (PDF) (48 pp, 632K, EPA-420-B-16-064, July 2016 )
    This document contains descriptions of the OMEGA model's operation, input and output files, and algorithms.
  • OMEGA 1.4.56 Installation Files (MSI)(1 pg, 4 MB, July 2016)
  • OMEGA pre-processors, Technology and Benefit-Cost Analysis files and OMEGA runs used in the Proposed Determination analysis
    These files contain technology cost development files including battery and motor cost development; the OMEGA Input/Output files used in the Proposed Determination analysis; and the OMEGA Inventory, Cost and Benefit Tool and Input/Output files. Please see the contained readme file for additional guidance.
  • OMEGA pre-processor, Technology cost development, and Input/Output files used in the Draft TAR analysis (ZIP)(1 pg, 731 MB, July 2016)
    This file contains technology cost development files including battery and motor cost development; the OMEGA Input/Output files used in the the Draft TAR analysis; and the OMEGA Inventory, Cost and Benefit Tool and Input/Output files. Please see the contained readme file for additional guidance. 
  • April 2017 revised OMEGA pre-processor, the TEB-CEB “Machine,” fixes formatting of technology codes on electrified vehicle packages where the safety-related net mass reduction cap is 0 percent 
    Three files, two Excel workbooks each with unique technology costs and a text file of the corrected VBA code

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OMEGA v1.4.1

(supporting the Final Rulemaking to Establish 2017 and Later Model Year Light-Duty Vehicle Greenhouse Gas Emissions Standards)

The downloadable installation file below contains the application executable file and five sample Microsoft Excel input files. In addition, a zip file contains the input files which were used to determine the technology cost estimates for the Final Rulemaking to Establish 2017 and Later Model Year Light-Duty Vehicle Greenhouse Gas Emissions Standards. Please note that the zip file is a large download.

  • Model Documentation v1.4.1 (PDF) (47 pp, 1.14MB, EPA-420-R-12-024, August 2012)
    This document contains descriptions of the OMEGA model's operation, input and output files, and algorithms.
  • OMEGA 1.4.1 Installation Files (MSI)(1 pg, 2 MB, August 2012)
    This file contains the OMEGA v1.4.1 application executable file and five sample input files.
  • Input and output files used in the Final Rulemaking (ZIP)(1 pg, 243 MB, August 2012)
    This file contains the input and output files used in the the Final Rulemaking to Establish 2017 and Later Model Year Light-Duty Vehicle Greenhouse Gas Emissions Standards, as well as the benefits worksheet. Please see the contained readme file for additional guidance.

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OMEGA v1.4.0

(supporting the Notice of Proposed Rulemaking to Establish 2017 and Later Model Year Light-Duty Vehicle Greenhouse Gas Emissions Standards)

The downloadable installation file below contains the application executable file and five sample Microsoft Excel input files. In addition, a zip file contains the input files which were used to determine the technology cost estimates for the Notice of Proposed Rulemaking to Establish 2017 and Later Model Year Light-Duty Vehicle Greenhouse Gas Emissions Standards.

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OMEGA v1.3.1

(supporting the model year (MY) 2017 - 2025 Interim Joint Technical Assessment Report of September 2010)

The downloadable installation file below contains the application executable file and five sample Microsoft Excel input files. In addition, a zip file contains the input files which were used to determine the technology cost estimates for the MY 2017-2025 Interim Joint Technical Assessment Report. The model documentation provides details on the model’s input files, algorithms, and output files.

  • Model Documentation v1.3 (PDF) (44 pp, 695K, EPA-420-B-10-042, October 2010)
    This document contains descriptions of the OMEGA model's operation, input and output files, and algorithms.
  • OMEGA 1.3.1 Installation Files (MSI) (1 pg, 625 K, October 2010)
    This file contains the OMEGA v1.3.1 application executable file and five sample input files. This version has some minor technical corrections relative to the version (1.3.0) used in MY 2017-2025 Interim Joint Technical Assessment Report.
  • Input files used in Interim Joint Technical Assessment Report (ZIP)(1 pg, 6 MB, October 2010)
    This file contains the input files used in the Interim Joint Technical Assessment Report, as well as the benefits post-processor worksheet.

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OMEGA v1.0.2

(supporting the MY 2012-2016 Light Duty Greenhouse Gas rulemaking)

The downloadable installation file below contains the application executable file and five sample Microsoft Excel input files. In addition, a zip file contains the input files which were used to determine EPA’s technology cost estimates for the EPA-DOT Joint Final Rulemaking (FRM) to Establish Light-Duty Vehicle Greenhouse Gas Emission Standards and Improve Fuel Economy. The model documentation provides details on the model’s input files, algorithms, and output files. A copy of the peer review report and EPA’s response to those comments can also be found below.

  • Model Documentation v1.0 (PDF) (54 pp, 308K, EPA-420-B-09-035)
    This document contains descriptions of OMEGA’s general methodology, the input and output files, and algorithms.
  • OMEGA v1.0.2 Installation file (MSI)(1 pg, 1 MB, October 2009)
    This file contains the OMEGA v1.0.2 application executable file and five sample input files. This version was used in EPA’s Final Rulemaking to Establish Light-Duty Vehicle Greenhouse Gas Emission Standards. (Requires the patch below)
  • Patch for OMEGA v1.0.2 (ZIP)(1 pg, 28 K, October 2009)
  • Input files used in EPA’s FRM (ZIP)(1 pg, 267 K, October 2009) This zip file contains 6 Excel files which were used to calculate manufacturers’ technology cost in EPA’s FRM.
  • Input files used in EPA’s NPRM (ZIP)(1 pg, 1 MB, October 2009)
    This zip file contains 28 Excel files which were used to calculate manufacturers’ technology cost in EPA’s NPRM.
  • Peer Review Report and Response to Comments (PDF) (156 pp, 2MB, EPA-420-R-09-016)
    This document contains the Peer Review Report, which is comprised of comments from three separate peer reviewers, and EPA’s response to those comments. 

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