Unless you are an electrician or an engineer, the difference between volts, amps, and watts probably don’t mean much to you. However, if you are an EV driver, you probably already know the difference between Level 1 and Level 2.
Isn’t all Level 2 charging the same? In fact, the rate of charging speed of Level 2 can vary greatly.
The math is actually quite simple: Volts * Amps = Watts. So, if you have your EV plugged into a 110v outlet at 16-amps (common in the U.S.), then you are getting a charge of 1,760 watts, or 1.76 kilowatts, and in an hour, you get 1.76 kilowatthours. So, to fill up the 10kWh of usable capacity in your Volt, it will take you 10/1.76, or about 5.68 hours to fully charge up.
Take that to a Level 2 charging station, and you can cut that time in half since you are now at 220v. Here’s where the difference in amps come in. A handful of Level 2 home charging stations, like the Voltec unit, are 16-amp units, meaning you can dispense 3.5 kilowatts in an hour. And for today’s Volt and LEAF, that’s just fine because the car’s onboard charger is rated at 3.3kW.
But the 2013 LEAF, the Fords, the Hondas, the BMWs, all have onboard chargers rated at 6.6kW. So, if you install a 16-amp Level 2 home station, you’re only going to be able to get half the speed you would get with a 30-amp unit (all commercial charging stations are 30A or better).
So, while it is a moot point if you drive a current generation Volt or LEAF, think about your NEXT car. Chances are your next electric vehicle will have a 6.6kW onboard charger. Our advice: Spend a bit more today and avoid having to upgrade your home charging station with your next car.