The Confusion of Units
Gas cars had one number: MPG. EVs have three: MPGe, Wh/mi, and kWh/100km. Here is how to read them.
The Benchmark: 3.0 mi/kWh
If your car gets 3.0 mi/kWh (333 Wh/mi), that is "Average." Anything above 4.0 is highly efficient. Anything below 2.5 is a "guzzler" (often large electric trucks).
Why Wh/mi matters
Tesla uses Watt-hours per mile (Wh/mi). Lower is better.
250 Wh/mi is great
efficiency.
350 Wh/mi is average.
500 Wh/mi is heavy towing/trucks.
One gallon of gasoline contains exactly 33.7 kilowatt-hours of potential energy.
So: 100 MPGe = 2.96 miles per kWh.