More About GREET


To fully evaluate energy and emission impacts of advanced vehicle technologies and new transportation fuels, the fuel cycle from wells to wheels and the vehicle cycle through material recovery and vehicle disposal need to be considered. Sponsored by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE), Argonne has developed a full life-cycle model called GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation). It allows researchers and analysts to evaluate various vehicle and fuel combinations on a full fuel-cycle/vehicle-cycle basis.

The first version of GREET was released in 1996. Since then, Argonne has continued to update and expand the model. The most recent GREET versions are the GREET1 2017 version for fuel-cycle analysis and GREET2 2017 version for vehicle-cycle analysis.

GREET was developed as a multidimensional spreadsheet model in Microsoft Excel. This public domain model is available free of charge for anyone to use.

GREET Model Tutorial Videos Tutorial                                        GREET Excel Tutorial

What's in GREET?

For a given vehicle and fuel system, GREET separately calculates the following:

  • Consumption of total resources (energy in non-renewable and renewable sources), fossil fuels (petroleum, natural gas, and coal together), petroleum, coal, natural gas and water.
  • Emissions of CO2-equivalent greenhouse gases - primarily carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O).
  • Emissions of seven criteria pollutants: volatile organic compounds (VOCs), carbon monoxide (CO), nitrogen oxide (NOx), particulate matter with size smaller than 10 micron (PM10), particulate matter with size smaller than 2.5 micron (PM2.5), black carbon (BC), and sulfur oxides (SOx).

Fuel Pathways

GREET includes more than 100 fuel pathways including petroleum fuels, natural gas fuels, biofuels, hydrogen and electricity produced from various energy feedstock sources

Vehicle Classes

GREET simulates the following three vehicle classes:

  • Passenger cars
  • Light Duty Truck 1 ( gross weight < 6000 lb)
  • Light Duty Truck 2 ( gross weight < 8500 lb)

Vehicle Technologies

GREET includes more than 80 vehicle/fuel systems covering the following vehicle technologies:

  • Conventional spark-ignition engine vehicles
  • Spark-Ignition, Direct-Injection Engine Vehicles
  • Compression-Ignition, Direct-Injection Engine Vehicles
  • Hybrid electric vehicles
    • Spark-ignition engines
    • Compression-ignition engines
  • Plug-in hybrid electric vehicles
    • Spark-ignition engines
    • Compression-ignition engines
  • Battery-powered electric vehicles
  • Fuel-cell vehicles