If electricity is 12 cents per kWh -- the national average -- it would cost $3.48 to go 100 miles. Another way to calculate cost is to use the number of kilowatt-hours it takes to recharge the EV's battery. If an EV requires 20 kWh to fully recharge and the rate is 12 cents per kWh, that's $2.40 to fill up the car.read more >>