Estimate the total cost to charge your EV based on your local electricity rates and battery size.
Energy to be Added:0 kWh
Energy Consumed (with loss):0 kWh
Total Estimated Cost:$0.00
How to Calculate Your EV Charging Costs
Understanding the cost of charging an electric vehicle (EV) is essential for budgeting and comparing your savings against traditional gasoline vehicles. Unlike gas prices, which are measured per gallon, EV charging is measured in kilowatt-hours (kWh).
The Charging Cost Formula
To calculate the cost of a single charging session, we use the following formula:
Battery Capacity: Larger batteries (like those in the Tesla Model S or Ford F-150 Lightning) require more energy to fill.
Electricity Rates: Residential rates vary significantly by region. Peak hours usually cost more than overnight charging.
Charging Efficiency: Not all energy from the wall reaches the battery. Heat loss and powering the car's thermal management systems usually result in an 85% to 95% efficiency rate.
Charger Type: Level 1 and Level 2 home charging is usually cheaper than Level 3 (DC Fast Charging) stations found on highways.
Example Calculation
If you have a Tesla Model 3 with a 60 kWh battery, and you want to charge from 20% to 80% at a rate of $0.13 per kWh with 90% efficiency:
Energy needed in battery: 60 kWh × 0.60 = 36 kWh
Energy drawn from grid: 36 kWh / 0.90 = 40 kWh
Total Cost: 40 kWh × $0.13 = $5.20
EV vs. Gas Comparison Table
Metric
Electric Vehicle (EV)
Gasoline Vehicle (ICE)
Unit of Energy
kWh
Gallon
Avg. Unit Price
$0.16 per kWh
$3.50 per Gallon
Avg. Range per Unit
3 – 4 Miles
25 – 30 Miles
Cost for 300 Miles
~$12.00 – $16.00
~$35.00 – $42.00
function calculateEVCharge() {
var batteryCapacity = parseFloat(document.getElementById("batteryCapacity").value);
var electricityRate = parseFloat(document.getElementById("electricityRate").value);
var currentSoc = parseFloat(document.getElementById("currentSoc").value);
var targetSoc = parseFloat(document.getElementById("targetSoc").value);
var efficiency = parseFloat(document.getElementById("efficiency").value);
// Validation
if (isNaN(batteryCapacity) || isNaN(electricityRate) || isNaN(currentSoc) || isNaN(targetSoc) || isNaN(efficiency)) {
alert("Please enter valid numbers in all fields.");
return;
}
if (targetSoc <= currentSoc) {
alert("Target charge must be higher than current charge.");
return;
}
if (efficiency 100) {
alert("Efficiency must be between 1 and 100.");
return;
}
// Calculations
var percentageToCharge = (targetSoc – currentSoc) / 100;
var netEnergyNeeded = batteryCapacity * percentageToCharge; // kWh added to battery
var grossEnergyNeeded = netEnergyNeeded / (efficiency / 100); // kWh pulled from grid
var totalCost = grossEnergyNeeded * electricityRate;
// Display Results
document.getElementById("energyAdded").innerHTML = netEnergyNeeded.toFixed(2) + " kWh";
document.getElementById("energyConsumed").innerHTML = grossEnergyNeeded.toFixed(2) + " kWh";
document.getElementById("totalCost").innerHTML = "$" + totalCost.toFixed(2);
// Show result area
document.getElementById("ev-result-area").style.display = "block";
}