EV energy cost per mile comes from the electricity price divided by miles per kilowatt-hour. Comparing it with gasoline requires consistent distance, efficiency, and price assumptions.
The EV formula
EV cost per mile = electricity rate ÷ vehicle efficiency. At $0.16 per kWh and 3.5 miles per kWh, the result is about $0.0457 per mile before charging losses and fixed fees.
Include charging losses
If wall-to-battery efficiency is 90%, divide the battery energy estimate by 0.90 or multiply the cost by 1 ÷ 0.90. Public charging fees may require a separate scenario.
Compare gasoline fairly
Gas cost per mile = gas price per gallon ÷ miles per gallon. Compare the same route and period, then include maintenance, access fees, and vehicle ownership separately if the question is total cost of ownership.
Use ranges
Traffic, weather, speed, heating, cooling, terrain, tire pressure, and rates change the result. A low/likely/high range is more useful than a single decimal presented as universal.
Sources
The figures and rules in this guide are checked against:
- Vehicle Cost Calculator — U.S. DOE Alternative Fuels Data Center
- Find and Compare Cars — fueleconomy.gov (U.S. DOE / EPA)
- Electric Vehicles: Learn More About the New Label (kWh/100 miles) — fueleconomy.gov (U.S. DOE / EPA)
- Gasoline and Diesel Fuel Update — U.S. Energy Information Administration