The Electric Vehicle (EV) Charging Cost Calculator computes the exact electricity expense to recharge an electric vehicle battery at home, including charging efficiency losses, cost per mile driven, and annual savings compared to gasoline.

### Charging Physics & Efficiency Formulas Calculating true EV charging cost requires accounting for the thermal and AC-to-DC conversion losses that occur in onboard chargers: - **Charging Efficiency**: Level 2 AC home chargers operate at roughly 90% electrical efficiency ($10\%$ lost to heat and onboard battery conditioning): $$\text{Grid Energy Consumed (kWh)} = \frac{\text{Battery Capacity (kWh)}}{0.90}$$ - **Full Charge Cost**: $\text{Grid Energy (kWh)} \times \text{Electricity Rate ($/kWh)}$ - **Driving Cost per Mile**: $\frac{\text{Full Charge Cost}}{\text{Full Charge Range (Miles)}}$ - **Annual Fuel Savings**: Assumes 12,000 baseline miles compared to a 28 MPG gasoline vehicle paying $3.50/gallon ($0.125/mile): $$\text{Annual Savings} = (12{,}000 \times 0.125) - (12{,}000 \times \text{Cost Per Mile})$$

### Worked Calculation Example Charging a 75 kWh battery with 300 miles of range at a residential utility rate of $0.15/kWh: - **Grid Energy Consumed**: $75 / 0.90 = 83.33\text{ kWh}$ - **Full Battery Charge Cost**: $83.33 \times \$0.15 = \$12.50$ - **Cost per Mile**: $\$12.50 / 300 = \$0.0417\text{/mile} \quad (\approx 4.2\text{ cents/mile})$ - **Gas Equivalent Baseline**: 12,000 miles in a 28 MPG car costs $1,500.00 in fuel. - **EV Annual Energy Cost**: $12{,}000 \times 0.0417 = \$500.00$ - **Annual Savings**: $\$1,500.00 - \$500.00 = \$1{,}000.00\text{ saved per year}$

### In-Browser Processing & Privacy All formulas execute client-side in your web browser. No vehicle models, home utility bills, or commute distances are uploaded to any server.