In some ways, the idea of Level 1, Level 2, and Level 3 charging is deceptive. On the surface, it makes sense to differentiate between slow 120 volt charging, faster 240 volt charging, and DC fast charging, but there’s quite a bit of variance in speeds within each level, and even some overlap.
For example, there’s a vast difference between 50 kW charging like you’d get with a Chevy Bolt or Nissan LEAF and 250+ kW charging like most more premium EVs offer. Is it fair to lump in something that adds 100 miles per hour of charging with something that adds 1000 miles per hour (both under ideal state of charge conditions, of course)? No, not really. But, they’re both “Level 3.”
Or what about what happens when a Nissan LEAF’s battery gets overheated? I’ve personally seen charging sessions as slow as 12 kW at a DC station, while you can easily go faster than that with a Tesla Model S using 240 volt charging. Plus, there’s the 22 kW 3-phase AC charging stations that are common in Europe and not really a thing in the United States. Technically, that’s Level 2, but it’s vastly faster than a common US Level 2 station that only provides 6.6 kW.
My Past Experience With This Left Me Thinking 6.6 kW Was The Best
My first EV (other than drones) was a 2011 Nissan LEAF. I never installed 240 volt charging at home for it because it was already pretty degraded when I bought it. There just wasn’t that much battery to charge up.
My second EV was a Chevy Volt. Like the LEAF, I didn’t initially worry about faster charging, but I figured out that the second trip in a day to pick up the kids was when the awful bark of the Volt’s ICE engine kicked in. So, I installed my first “Level 2” station (a hacked 120 volt EVSE that put out 3.3 kW). That made for fast enough charging to leave two or even three times a day with a full battery and I used zero gas for local driving from then on.
My second LEAF could do 6.6 kW charging, and that was plenty. The 40 kWh battery always charged up overnight, even if almost dead, and I even charged up at RV parks on some road trips that I never should have taken that car on. 6.6 kW became the norm for anything that wasn’t DC fast charging.
People who’ve had faster charging Teslas for years and took road trips using faster destination chargers (back before the Supercharger network was so widespread) know that 6.6 kW isn’t very fast. But, until recently, it was all that my car could do, and it’s still all that most public Level 2 charging stations do in the United States.
With the limits of my car and the limits of most stations, I really thought anything else was pointless. For example, I figured that the 19.2 kW charging that Lucid now offers was largely pointless.
Using An 11.5 kW (240v, 48 amp) Station In The Wild
The Chevy Bolt EUV I bought a couple of months ago had a feature that I figured I probably would never use: 11.5 kW Level 2 charging. 240 volts at 48 amps comes out to about 11.5 kW, and that’s almost twice as fast as what you’ll often see in most EVs. But, even with a faster onboard charger, you can only pull that power which a station can provide, so the 11.5 kW capability is only rarely used.
But, then I decided to take a trip across Texas to see a loved one who had recently been diagnosed with cancer. The interstate highways all have Electrify America charging stations, but it doesn’t make much sense to drive all the way to Fort Worth or San Antonio to get from El Paso to Dallas, and any opportunity to cut the corner can save you a lot of time.
So, as I planned the trip, I checked to see if a Level 2 charging stop in Fredericksburg would be feasible. It turned out that the little plaza in the middle of town had a nearby 48 amp/11.5 kW charging station. My family really likes to stop there and check out the shops, and just charging for a couple of hours would be enough to add 30%. That’s nothing compared to DC fast charging, but it’s enough to still be meaningfully more than 6.6 kW if you’re already someplace where you plan to spend time.
So, while we spent money at junk shops, walked around, and ate the best German food we could find (a number of Texas towns like this one were settled historically by Germans, and I’m among their descendants), the car picked up plenty of charge to make it the rest of the way to Austin without needing to stop at a fast charger toward the end.
Why I Just Put In 11.5 kW Charging At Home
I’m going to write another article detailing the process of working with GM and my local electric utility to set up a faster Level 2 charging station, but for the purposes of this article, it’s enough to say that the process got completed, and just recently.
Instead of relying on the included dual voltage EVSE Chevy included with the Bolt EUV, I had the electrician wire the whole thing up for 60 amps and install the Emporia charging station I reviewed back in July. Its maximum power rating is 48 amps, and that’s about as much as the Bolt EUV’s 11.5 kW onboard charger can pull.
It certainly would have been easier to put in a 32 amp charging station, but where I live, there’s not much in the way of Level 3 public charging stations. When I drive an unexpectedly long day, like say a trip to El Paso, it’s not too hard to come home with a nearly-dead battery. Two nearby car dealers have DCFC, but only when they’re open. If I need to stop at home for a few after dealer hours and run out again a while later, being able to add 40 miles per hour of charging instead of just 20-25 means that the Bolt gets back in action a lot faster.
As public charging infrastructure gets better and the nearest fast charging station that’s open 24 hours isn’t 60 miles away from home, such a fast home charging station will become a lot less useful and important. I know for many readers, we’re already there. But, for many people in my shoes, living far from even a medium-sized city, it still makes a lot of sense.
Featured image by Jennifer Sensiba.
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