Updated October 26, 2026 with EIA August 2026 prices
Methodology
Charging cost = miles × (EPA kWh per 100 miles ÷ 100) × residential electricity price. EPA measures energy at the wall, so charging losses are included and no extra loss factor is added.
Data sources
| Data | Source | Current period | Update frequency |
|---|---|---|---|
| Residential electricity price by state | EIA Electric Power Monthly, Table 5.6.A | August 2026 | Monthly, about two months after the data month |
| Regular gasoline price by region | EIA Gasoline and Diesel Fuel Update | October 19, 2026 | Weekly |
| Vehicle efficiency and range | EPA / DOE fueleconomy.gov dataset | Retrieved October 26, 2026 | Checked monthly |
Formulas
- Cost per mile = kWh per 100 miles ÷ 100 × price per kWh.
- Monthly cost = cost per mile × miles per year ÷ 12. Default: 13,500 miles a year.
- Full charge = EPA range × kWh per 100 miles ÷ 100 × price — the energy to drive the full rated range.
- Public charging mix = the price is blended: (1 − share) × home price + share × public price.
- Gas car cost = miles ÷ mpg × gasoline price. Default: 30 mpg.
- Break-even electricity price = (gas price ÷ mpg) ÷ (kWh per mile).
- Charging time = (miles to add × kWh per 100 miles ÷ 100) ÷ charger power in kW.
Reference EV and averages
"Typical EV" means 33.5 kWh/100 mi (median of 26 popular EV models, model years 2025–2027). The national comparison uses the EIA U.S. average residential price. Gas prices for each state use the EIA regional series for that state (PADD), with California's own series.
Limitations
- State averages include all residential customers; your utility, plan and tiered pricing may differ. Enter your own price in any calculator.
- Real-world consumption varies with temperature, speed, tires and load.
- Charging time is an average; charging slows near a full battery and may be capped by the car's onboard charger.