Miles per Gallon Equivalent (MPGe)
Miles per gallon equivalent (MPGe) is an EPA energy-efficiency metric that expresses how many miles a plug-in vehicle travels on energy equivalent to one U.S. gallon of gasoline.
What the number means
EPA uses 33.7 kWh of electricity as the energy equivalent of one gallon of gasoline. A vehicle that uses 33.7 kWh to travel 100 miles therefore scores 100 MPGe. A higher MPGe means less energy is used per mile under the EPA procedure.
For plug-in vehicles, EPA label MPGe includes charging losses and assumes Level 2 AC charging, moving the measurement boundary to electricity drawn from the wall. It is therefore different from a battery-to-wheels consumption number. The boundary must be kept consistent when converting between MPGe and kWh per distance.
MPGe is not fuel cost, carbon emissions, battery capacity, or range. Electricity and gasoline prices differ, upstream energy sources differ, and two vehicles with the same MPGe can have different battery sizes and travel distances. It is primarily a common energy-equivalent label for comparison under one test system.
For the EPA test procedure and range interpretation, see EPA Range Testing.