An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Regulations for Emissions from Vehicles and Engines

Lumped Parameter Model (LPM) for Light-Duty Vehicles

EPA’s Lumped Parameter Model (LPM) is a free, desktop computer application that estimates the effectiveness (i.e., carbon reduction) of various technology combinations, or “packages,” in a manner that accounts for synergies between technologies.

LPM v3.10

EPA used LPM V3.10 to support the 2016 Draft Technical Assessment Report.

LPM v2.12

EPA used LPM V2.12 to support the 2017-2025 Final Light-Duty Vehicle Greenhouse Gas Rulemaking.

Regulations for Emissions from Vehicles and Engines Home