| mi/kWh | Wh/mi | MPGe |
|---|
Measuring EV Efficiency
EV efficiency is how far you travel per unit of energy. Divide miles driven by kWh used and you get miles per kWh, the cleanest measure of how economical your driving is. From that single figure you can also express consumption as Wh per mile and as MPGe, the gasoline-equivalent rating used on window stickers.
Three Numbers, One Reality
Miles per kWh, Wh per mile, and MPGe all describe the same energy use from different angles. Miles per kWh and MPGe rise as you get more efficient; Wh per mile falls. MPGe converts energy to a familiar scale by treating 33.7 kWh as one gallon of gasoline, which is handy when comparing an EV to a gas car.
What Changes Your Efficiency
Speed is the biggest factor on the highway because drag rises with the square of speed. Cold weather hurts both the battery and cabin heating, big wheels and aggressive tires add rolling resistance, and a heavy right foot wastes energy. Smooth driving, moderate speed, and preconditioning while plugged in all push efficiency up.
Frequently Asked Questions
What is a good mi/kWh figure?
Around 3.5 to 4.5 is efficient for most EVs in mixed driving. Large, heavy, or performance EVs sit lower; small, aero-focused ones can exceed it.
How is MPGe calculated?
Multiply miles per kWh by 33.7, the kWh of energy in a gallon of gasoline. It lets you compare an EV to a gas car on one scale.
Why is my winter efficiency so low?
Cold reduces battery performance and the cabin heater draws significant power. Both cut miles per kWh, sometimes sharply on short trips before the car warms up.