How to use the EV Charging Cable Power Loss Calculator
The Formula
Every amp through copper creates I²R heat in the conductors. Long thin extension cords add resistance in series with the charger—energy becomes warmth in the jacket instead of kilowatt-hours in the pack. You still pay the utility for those losses.
Practical Example
Round-trip Ω ≈ 2 × (0.0175 × length m ÷ mm²). Loss W = I² × Ω. Wasted kWh = W × hours ÷ 1000. Session $ = kWh × your rate. Loss % compares to I × 230 V reference charge power.