Calculator
Car energy efficiency
Before you buy an electric vehicle: how will air temperature where you live affect its range and charging cost, and how much CO2 does charging it from your state's grid emit?
This is the original spreadsheet version. Try the new calculator.
EV range by month
Enter the range published by the manufacturer to see the range you can expect each month.
Select a state and enter a range to see results.
| Month | Average temperature | Warm days | Cold days |
|---|
Compare vehicles
Compare up to three 2025–2026 vehicles on energy use, charging cost, and CO2 per mile, adjusted for temperature in the state where each one is driven.
| Vehicle 1 | Vehicle 2 | Vehicle 3 |
|---|
Gas vehicles don't charge from the grid, so their energy and cost rows show "—". Plug-in hybrid CO2 = grid emissions for the electric share + EPA tailpipe CO2.
Data sources
- Vehicle efficiency and CO2: U.S. DOE / EPA, fueleconomy.gov model year 2025 and 2026 data files.
- State monthly temperatures: NOAA NCEI 1991–2020 monthly normals, for one representative city per state.
- Electricity CO2 intensity: U.S. EIA state electricity profiles, 2024.
- Range vs. temperature: The Chart Nissan LEAF average range as a function temperature/Data from Fleet Carma via “Effects of Regional Temperature on Electric Vehicle Efficiency, Range, and Emissions in the United States” from the article by David Reichmuth “Do Electric Cars Work in Cold Weather? Get the Facts…”, February 16, 2016, The Equation, Union of Concerned Scientists, https://blog.ucs.org/dave-reichmuth/electric-cars-cold-weather-temperatures/