Compare the annual cost of driving an electric car vs a gas car and see how much you could save on fuel and maintenance.
Situation: 12,000 miles/year, gas car at 30 mpg, gas at $3.50/gallon. EV at 30 kWh/100mi, charged 80% at home ($0.16/kWh) and 20% at public chargers ($0.45/kWh).
Gas cost: 12,000 ÷ 30 × $3.50 = $1,400/year
EV cost: 3,600 kWh × (80% × $0.16 + 20% × $0.45) ≈ $806/year
Savings: ~$594 fuel + $600 maintenance ≈ $1,194/year
Situation: 20,000 miles/year, gas at $3.50/gallon, 30 mpg. EV at 28 kWh/100mi, 95% charged at home with cheap solar ($0.08/kWh) and 5% at public chargers ($0.45/kWh).
Gas cost: 20,000 ÷ 30 × $3.50 ≈ $2,333/year
EV cost: 5,600 kWh × (95% × $0.08 + 5% × $0.45) ≈ $552/year
Savings: ~$1,781 fuel + $1,000 maintenance ≈ $2,781/year
Situation: Low-mileage driver: 6,000 miles/year, very efficient gas car at 40 mpg, cheap gas at $2.80/gallon. EV at 34 kWh/100mi, but only 20% charged at home ($0.16/kWh) and 80% at expensive public chargers ($0.50/kWh).
Gas cost: 6,000 ÷ 40 × $2.80 = $420/year
EV cost: 2,040 kWh × (20% × $0.16 + 80% × $0.50) ≈ $881/year
Savings: −$461 fuel + $240 maintenance ≈ −$221/year
The calculator compares annual fuel/energy costs and maintenance costs for an EV and a gas car, then works out your total yearly savings and how long it takes the EV's price premium to pay for itself.
Gallons per year = Miles ÷ MPG
Example: 12,000 ÷ 30 × $3.50 = $1,400/year
kWh per year = Miles ÷ 100 × kWh per 100 miles
Example: 12,000 mi at 30 kWh/100mi → 3,600 kWh → ≈ $806/year
Example: $5,000 premium ÷ ($1,194 ÷ 12) ≈ 50 months
kWh per 100 miles is the EV equivalent of gallons per 100 miles — lower is better. Miles per kWh is the EV equivalent of MPG — higher is better. They convert directly: kWh/100mi = 100 ÷ mi/kWh. For example, 3.3 mi/kWh ≈ 30 kWh/100mi, and 4 mi/kWh ≈ 25 kWh/100mi.
| Efficiency | kWh per 100 miles | Cost per 100 mi @ $0.16/kWh |
|---|---|---|
| Efficient small EV | 25 | $4.00 |
| Typical EV | 30 | $4.80 |
| Large SUV / truck | 40 | $6.40 |
Public fast chargers cost 2–3× more per kWh than home electricity. Charging at home is the #1 factor in EV payback.
Many utilities charge less overnight. Set your EV to charge after 9–11 PM and cut electricity costs by 20–40%.
Some states add $100–$225 per year in EV fees to replace lost gas taxes. Include this in your comparison.
Efficiency can drop 10–30% in freezing temperatures. Plan for lower real-world range in winter.
The biggest difference between a gas car and an electric car is the cost of "fuel." A gas car burns gasoline measured in gallons, while an EV stores energy in a battery measured in kilowatt-hours (kWh). Because electricity is usually much cheaper per mile than gasoline, EVs typically cost less to drive — especially if you charge at home.
A typical gas car gets 25–35 mpg. At $3.50/gallon, every 1,000 miles costs roughly $100–$140 in fuel. Maintenance adds oil changes, spark plugs, belts, and more frequent brake wear.
A typical EV uses 25–35 kWh per 100 miles. At $0.16/kWh at home, every 1,000 miles costs roughly $40–$56 in electricity — about 60% less than gas. Regenerative braking also extends brake life.
Where you charge determines most of your EV savings. Home electricity rates average $0.14–$0.20 per kWh in the U.S., while public DC fast chargers often charge $0.40–$0.60 per kWh — 2 to 3 times more. Charging mostly at home is the single biggest factor in EV payback.
Typical cost $0.10–$0.20/kWh. A Level 2 charger adds about 25–40 miles of range per hour, so overnight charging covers almost any daily commute. Pair it with a time-of-use rate to pay even less.
Fast chargers typically cost $0.35–$0.60/kWh. They are convenient for road trips but expensive for daily use. If you cannot charge at home or at work, EV savings shrink dramatically.
Fuel and maintenance savings are only part of the story. Before you switch, factor in these additional costs:
Estimates Only: Actual efficiency depends on driving style, weather, and terrain; electricity and gas prices vary by location; check state EV registration fees. Results are estimates for educational purposes and do not constitute financial advice.