EV Charging Cost Calculator Formula
Understand the math behind the ev charging cost calculator. Each variable explained with a worked example.
Formulas Used
Cost Per Charge
charge_cost = kwh_needed * electricity_ratekWh From Wall
kwh_consumed = kwh_neededMonthly Cost (8 charges)
monthly_cost_est = kwh_needed * electricity_rate * 8Variables
| Variable | Description | Default |
|---|---|---|
battery_kwh | Battery Capacity(kWh) | 75 |
charge_pct | Charge From/To Range(%) | 80 |
electricity_rate | Electricity Rate(USD/kWh) | 0.14 |
charger_efficiency | Charger Efficiency(%) | 90 |
kwh_needed | Derived value= battery_kwh * charge_pct / 100 / (charger_efficiency / 100) | calculated |
How It Works
How EV Charging Costs Work
The cost to charge depends on battery capacity, how much charge you add, your electricity rate, and charger efficiency.
Formula
kWh From Wall = Battery kWh x Charge % / Charger Efficiency
Cost = kWh x Electricity Rate
Level 2 home chargers are typically 85-95% efficient.
Worked Example
75 kWh battery, charging 80%, $0.14/kWh, 90% efficiency.
battery_kwh = 75charge_pct = 80electricity_rate = 0.14charger_efficiency = 90
- 01Energy needed = 75 x 80% = 60 kWh to battery
- 02From wall (90% efficiency) = 60 / 0.90 = 66.7 kWh
- 03Cost = 66.7 x $0.14 = $9.33
- 04Monthly (8 charges) = $9.33 x 8 = $74.67
Ready to run the numbers?
Open EV Charging Cost Calculator