Thank you for reading my series about exploring America with an electric vehicle. If you’re interested in purchasing a Tesla, contact me for a referral code, which entitles you to $1,000 off the purchase price and, possibly, free supercharging for as long as you own the vehicle. See all posts in this series at the GAMR 2017 tag.
As I discussed in my first post in this series, electric vehicles use a variety of charging standards, which we categorize as Level 1 (L1), Level 2 (L2), and Level 3 (L3). L1 charging is the slowest and L3 charging the fastest. Level 2 charging is the sweet spot for most daily use.
Today, I’ll dig a bit deeper into those charging standards and then show how that translates into reality during a long road trip.
In my previous post, I discussed thinking in terms of kiloWatt hours instead of gallons of gasoline. The same applies for charging. The question to ask is: How many kiloWatts can a given charger or electrical circuit supply to the car? To answer that question, you need to know the voltage and amperage of the circuit because you multiply the two to get the circuit’s power in Watts.
Example: A traditional home outlet is an 110 Volt/15 Amp circuit that can theoretically supply an EV with 1,650 Watts (110*15) of instantaneous power. Sustained over an hour, that becomes 1,650 Watt hours per hour (1.6 kWh per hour). In reality, you can’t use a circuit at its maximum, so, in daily use, a standard home outlet can supply an EV with 90% of that power (typically 12 Amps) or 1.32 kW (110*12=1,320 Watts). My Model S has an 85 kWh battery so it would take approximately 65 hours to completely charge from zero using a standard outlet (85 divided by 1.32). That is a long time.
Obviously, it is a pain in the butt to do all these calculations and keep all the units straight, so we use L1, L2, and L3 to simplify the process by categorizing circuits and chargers
- L1: Think of a standard outlet. L1 circuits typically add 2 kWh per hour or less to your car, which equates to days to fully charge a 60 kWh or larger battery.
- L2: Think of a dryer circuit. L2 circuits typically add about 6.6 kWh per hour (aka 6.6 kW) to your car, but circuits can range from 3.3 to 11 kW. A 6.6 kW L2 would take approximately nine hours to fully charge a 60 kWh.
- L3: “fast charging” is typically 50 kW or greater. Tesla’s superchargers are capable of about 120 kW at peak rates. With L3 charging, a 60 kWh battery can be fully charged in an hour or so. A special note: L3 chargers adjust their power levels based on temperature, battery capacity, battery state of charge, and other factors to protect the battery. L3 chargers provide peak power when the battery is warm and nearly empty. Charging at L3 rates is an intricate dance between the electrical grid, car, and charger. (Note: see my follow-up post, which describes this dance in more detail)
Road tripping requires covering significant distances. A good rule of thumb is 500 miles of travel per day. For my Model S, that means the equivalent of about two full charging sessions. Now that you know about L1, L2, and L3 charging rates, you can see why a robust Level 3 network is essential for road trips.
The United States currently has three Level 3 charging standards for passenger vehicles: CHAdeMO, CCS, and Tesla. CHAdeMo and CCS are open standards while the Tesla network is proprietary.
Plugshare.com makes it easy to find L3 charging. Green pins show L1 and L2 charging stations while orange pins show L3 stations.
The following pictures show some common charging stations and connector standards.
Other than Tesla, the Chevrolet Bolt is the only electric vehicle that I consider capable of undertaking a road trip (see my first post for why). However, the Bolt does not come standard with Level 3 capabilities. CCS charging is available as an option. Because CCS is the least robust L3 network, the Bolt is untenable as a road trip EV. In fact, Chevrolet doesn’t try to market the Bolt as a road trip car; instead, they call it an urban EV. For now, the Bolt is an ultra-capable EV that can take you on long day trips around or between nearby cities but not country-wide road trips.
All Teslas can obviously use the Tesla network and, with an adapter, the CHAdeMO network, which makes them uniquely suited to country-wide road trips.
Tesla made it a priority to develop a robust supercharging network and plans to triple the network’s size by the end of 2018. Tesla owners can already travel to almost every part of America. It is anyone’s guess how the charging infrastructure standards will sort themselves out over the next decade. I suspect two standards will eventually dominate just like we have two major smartphone frameworks (iOS/iPhone and Android.)
The image below is a screen capture from supercharge.info (see my previous post on tools for road tripping an EV) of the supercharger network in the parts of the country we are traveling for this road trip.
How does this work in practice? On this road trip, I’ve used all three levels of charging (L1, L2, and L3). I’ve primarily relied upon the L3 Tesla supercharging network, but I’ve also used an L2 Tesla “destination charger” provided by the InterContinental hotel in Milwaukee and L1 charging (standard outlets) at the hotel in Bayfield, WI and at my dad’s house in Minnesota.
Superchargers are now so prevalent that it isn’t always necessary to stop at each one. In the image below, I’ve turned on a 200-mile range ring for three supercharger locations we’ve used on this trip (Lexington, VA, Lafayette, IN, and Oakdale, MN). Lenny can theoretically travel 265 miles on a charge, but I’ve chosen a 200-mile range ring to show that it isn’t necessary to push the limits. Most of the time, we charge for awhile and go. It is only in a few instances where our plans require going off the beaten path that care needs to be taken to ensure we have enough range to make the next charging location.
I also have accounts with ChargePoint, EVgo, Blink, and Greenlots to access their L2 and CHAdeMO networks. I haven’t needed to use any of these on this road trip, but they significantly expand the charging options available.
We had two range-related challenges on the trip to Minnesota and will have a third one on our return trip.
Our visit to the Apostle Islands in Wisconsin was the most challenging part of our trip from a charging perspective. I can often find a CHAdeMO charger in the gaps between superchargers. Not so in Northern Wisconsin, so we had to get creative. With a full charge at the Wausau, WI supercharger, we would almost have enough electricity to make it to the Apostle Islands and then to the Duluth, MN supercharger, but not quite. Plugshare.com showed a campground outside Bayfield with 220-volt circuits, but for a variety of reasons that wasn’t right for us. We needed another solution, so we called the few hotels in Bayfield.
The Bayfield Inn agreed to make an outlet available. As you now know, an outlet is Level 1, which means it would take multiple days to charge fully. However, we didn’t need to “fully” charge. We only needed to regain about 30–50 miles of range (about 15 hours of charging), and we planned to be there for two days so this solution would be acceptable. Here is a short video I captured just after arriving at the hotel.
It was clear the hotel had provided charging before as they had a pre-made cone reserving the area for electric vehicle charging. I didn’t expect to see another Tesla in Bayfield, but a Tesla Model S from Florida arrived the next day and plugged into a second outlet.
Plugshare.com is a crowdsourcing platform, so I added a pin to inform others that Bayfield Inn is an option for those traveling to the area.
In Ohio, we wanted to drive along the river between the Charleston, West Virginia, and Cincinnati, Ohio, superchargers (see map below). However, I failed to give this segment the due diligence it deserved. In Charleston, we only charged to 90%, per standard practice, which nets us about 200 miles of usable range and about 40 miles of margin. Google shows the route as 224 miles. Our first stop of the day was the Blenko Glass Company in Milton, WV. When we finished there, I finally thought to confirm we’d have enough range to make it to the Cincinnati supercharger. Oops. Maybe we could make it, but it would use virtually all of our margin and the only charging solutions along that route were two Level 2 chargers. Rather than spend two to three hours charging on a Level 2 charger, we rerouted straight West to the Lexington Kentucky supercharger.
We took the change in plans as an opportunity to visit Thoroughbred Park, which chronicles the town and state’s long history of horse racing. In the end, I think our short visit to Lexington was more interesting than the route along the river would have been, especially given the weather that day.
We are now in Minnesota and will soon be heading back to Washington, D.C. Our route back will be straight down I35 into Ohio, head Southeast through Pioria to Indianapolis and then straight East on I-70. In Iowa, we intend to stop at the Field of Dreams movie site in Dyersville. To get there with Lenny will require virtually all of our range. We will charge to 100% at the Dows, Iowa supercharger, which will net us about 264 miles of range. Google Maps shows the distance from Dows to Dyersville to the Davenport, Iowa supercharger as 235 miles, so that should still provide us with about 30 miles of margin for emergencies, detours, or any other unexpected situations.
As long as I don’t forget to charge to 100%, we’ll be okay.
In summary, road tripping a Tesla is simple with only a few exceptions, which are becoming fewer all of the time as the supercharging network grows. The capabilities of the non-Tesla L3 charging infrastructure prohibits multi-thousand-mile road trips in other electric vehicles for the moment. It remains uncertain whether other auto manufacturers will deem it important enough to partner with Tesla or increase the non-Tesla L3 charging infrastructure to enable cross country travel with other EVs. I suspect they will, but the automotive landscape is changing so quickly that many futures are possible. I may explore this theme further in upcoming posts.
I hope you’ve found this post useful. What questions do you have? What topics need further clarification or elaboration? Let me know with a comment.
