They take the energy content of a gallon of gasoline when burned (for the EPA, 33.7 kWh) and convert the efficiency from miles/kWh to mpg using that figure. Mo

They take the energy content of a gallon of gasoline when burned (for the EPA, 33.7 kWh) and convert the efficiency from miles/kWh to mpg using that figure. More information: https://en.wikipedia.org/wiki/Miles_per_gallon_gasoline_equivalent https://en.wikipedia.org/wiki/Miles_per_gallon_gasoline_equi...