Frequently Asked Questions
How much does it cost to charge an electric car?
At the US average electricity rate of $0.16/kWh, charging a Tesla Model 3 (57.5 kWh battery) from empty to full costs about $9.20, giving roughly $0.034 per mile. This is about 3-4× cheaper than a comparable gas car. Costs vary significantly by location: California averages $0.32/kWh (full charge ~$18.40), while Texas averages $0.12/kWh (full charge ~$6.90). DC fast charging at public stations typically costs $0.35-$0.50/kWh, roughly comparable to gas prices on long road trips.
How much can I save switching to an electric car?
The average US driver (12,000 miles/year) saves $800-$1,200 annually on fuel by switching from a 25 MPG gas car to an efficient EV. At California rates ($0.32/kWh electricity, $4.50/gallon gas), annual savings can reach $1,500+. When combined with rooftop solar, savings can exceed $2,000/year. Over a 10-year ownership period, fuel savings alone can total $8,000-$15,000, not counting lower maintenance costs (no oil changes, fewer brake replacements, simpler drivetrain).
What is the cost per mile: EV vs gas?
A typical EV costs $0.03-$0.05 per mile in electricity (at $0.12-$0.32/kWh rates). A 25 MPG gas car at $3.50/gallon costs $0.14 per mile. EVs are approximately 3-4× cheaper per mile than comparable gas cars. This advantage is largest where electricity is cheap and gas is expensive (e.g., Pacific Northwest with hydro power: $0.08/kWh and $4.00/gallon gas → EV ~$0.015/mile vs gas ~$0.16/mile, a 10× difference).
Is it cheaper to charge an EV with solar panels?
Yes — with rooftop solar, the marginal electricity cost drops to the solar system's levelized cost (~$0.05-$0.08/kWh), reducing per-mile cost to $0.01-$0.02. This makes daily driving nearly free after the solar installation is paid off. A typical 6 kW solar system generates enough electricity for ~15,000 miles of EV driving annually. The solar + EV combination provides the lowest possible transportation energy cost available to consumers today, with zero tailpipe AND zero smokestack emissions.
How does charging efficiency affect cost?
EV charging is not 100% efficient — some electricity is lost as heat during AC-to-DC conversion. Level 1 (110V) charging is ~80-85% efficient; Level 2 (240V) is ~88-92% efficient; DC fast charging is ~90-95% efficient. This calculator defaults to 90% efficiency (Level 2 typical). At this rate, for every 100 kWh drawn from the grid, about 90 kWh reaches the battery. This 10% loss adds roughly $0.003/mile at average electricity rates — significant over a vehicle's lifetime but small on a per-charge basis.
Understanding EV Charging Costs
The cost to charge an electric vehicle depends on three factors: battery capacity (kWh), electricity rate ($/kWh), and charging efficiency. The formula is simple: Full Charge Cost = Battery Size (kWh) × Electricity Rate ($/kWh) ÷ Charging Efficiency. For example, a 75 kWh Tesla Model Y charged at $0.16/kWh with 90% efficiency costs 75 × 0.16 ÷ 0.90 = $13.33 for a full charge that provides ~330 miles of range — approximately $0.04 per mile.
Charging costs vary dramatically by location and charging method. Home charging (Level 2, 240V) is the most economical at $0.10-$0.35/kWh depending on your utility rate. Public Level 2 chargers often cost $0.20-$0.40/kWh. DC fast charging (Tesla Supercharger, Electrify America, EVgo) costs $0.35-$0.60/kWh — competitive with gas for long trips but not ideal for daily use. Time-of-use electricity plans can slash home charging costs to $0.05-$0.08/kWh by charging overnight during off-peak hours, cutting per-mile costs to under $0.02.
Popular EV Models: Battery Size & Range
| Model | Battery (kWh) | EPA Range (mi) | Efficiency (mi/kWh) | Full Charge Cost* |
|---|
| Tesla Model 3 (RWD) | 57.5 | 272 | 4.7 | $9.20 |
| Tesla Model Y (LR AWD) | 75.0 | 330 | 4.4 | $12.00 |
| Ford F-150 Lightning (ER) | 131.0 | 320 | 2.4 | $20.96 |
| Chevy Bolt EV | 65.0 | 259 | 4.0 | $10.40 |
| Hyundai Ioniq 5 (LR RWD) | 77.4 | 303 | 3.9 | $12.38 |
| Tesla Cybertruck (AWD) | 123.0 | 340 | 2.8 | $19.68 |
* At US average $0.16/kWh. Actual range varies with temperature, driving speed, and terrain.