From Open Energy Information

Logo: The Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation Model (GREET)

The Department of Energy's Clean Cities Program has enlisted the expertise of Argonne to assist in measuring the petroleum displacement and greenhouse gas (GHG) emissions of medium- and heavy-duty vehicles and off-road equipment. Argonne has developed the GREET Fleet Footprint Online Calculator for Clean Cities stakeholders to estimate these values using simple spreadsheet inputs.

Based on GREET. The basis of this calculator is Argonne's Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) fuel-cycle model which is used to generate necessary petroleum use and GHG emission co-efficients of key fuel production pathways and combustion fuel types.

Well-to-Wheels Results. Fleet managers can quickly insert their data to generate petroleum use and GHG emissions on a well-to-wheels (WTW) basis. A WTW analysis can be divided into two stages: well-to-pump (WTP) and pump-to-wheels (PTW). The WTP stage starts with the fuel feedstock recovery, followed by fuel production, and ends with the fuel available at the pump, while the PTW stage represents the vehicle's operation activities. It is important to examine transportation fuels and technologies on a WTW basis in order to properly compare alternatives, as activities upstream of vehicle operation can use significant amounts of energy and subsequently produce a large amount of emissions.