Reader Rides: Electric Car DC Quick Charging Works Perfectly, But We Really Need More Charging Stations

I’ve been driving my 2012 Toyota Rav4 EV electric car for two and a half years now. Over 35,000 miles my EV has met my daily driving needs and provided the range to drive well over 100 miles to camp grounds, state parks, Bay Area cities, Napa Valley and more, where I can then use charging stations to charge up for the trip home.

I can drive to most regions within this green circle on a single charge.

I can drive to most regions within this green circle on a single charge.

To illustrate this point, on the left is a map of California centered on my town, with a 100 mile radius indicated in green overlaid on the map.  I’ve driven to many locations within the green circle on a single charge.  Driving to higher altitudes, for example to Lake Tahoe, would of course require an extra charge because it takes more energy to climb mountains.

During a typical work week I drive about 50 miles a day commuting to and from work and running errands, and log about one hour of driving time each day.  Every other day I plug in my EV for about 5 hours and charge the battery pack on my Rav4 EV to about 80% capacity.  I either charge at work while I’m in my office, or at home in my garage while I’m sleeping.

The Rav4 EV has a ‘Level 2’ charge port that accepts up to 240 volts and 40 amps, or nearly 10 kilowatts of power.  Most charging stations provide 6 or 7 kW of power, resulting in about 20 miles of range being added to the battery for each hour of charging.  This works fine for my daily commute to work during the week, for errands, trips to the grocery market, and weekend excursions to some of our favorite places in our region of California.

But there are times when having the ability to quickly charge an EV is a great benefit.  That’s why Nissan, BMW, Kia, Volkswagen, GM, Mitsubishi (and of course Tesla) make battery powered electric cars that have a DC rapid charging port.  For the non-Tesla EVs these are called DC quick charge (DCQC), or DC fast charge (DCFC) ports.

During the week I drive about 50 miles a day, and usually charge my EV to 80% capacity every other day. The red line shows the rate at which battery State of Charge increases during charging.

During the week I drive about 50 miles a day, and usually charge my EV to 80% capacity every other day. The red line shows the rate at which battery State of Charge increases during charging.

Toyota did not provide the Rav4 EV with a DCQC port.  But 6 weeks ago I purchased a CHAdeMO DC quick charge port, called JdeMO and made especially for the Rav4 EV by Quick Charge Power.  I’ve since put the JdeMO port to use a number of times and it has changed the calculus for how I drive my EV. (For more information about the benefits and costs of DC rapid charging, see this Transport Evolved post.)

Here’s an example.  Last week I visited a research group I work with in Merced, CA.  The trip was just over 130 miles one way.  I stopped once for 30 minutes on the way down, and once for 30 minutes on the trip home to recharge on DCQC stations.  I drove along CA Route 99 which has decent coverage with DCQC charging stations.

I have a MyCarma data logger that records the distance and time of each trip, and battery state of charge at the beginning and end of each trip.  I’ve plotted the data collected during my trip to Merced in a chart to demonstrate how DCQC facilitates travel – sourced from domestic power – for cleaner, efficient, longer distance driving.  For a comparison, I’ve plotted how long my charging stops would have been to reach the same state of charge if I had instead used Level 2 charging stations.

Comparing the total driving and charging time using DCQC versus Level 2.

Comparing the total driving and charging time using DCQC versus Level 2.

Panel A in the figure above shows the total driving and charging time for my trip using DCQC stations.  Panel B shows the route I took, indicated by the blue line.  The location of DCQC charging stations is marked with orange icons (data from  Panel C shows how long my driving and charging time would have been for the same trip if I had used Level 2 charging stations.

As you can see in Panel A, I started with a full battery.  It was a chilly 48 degrees with light rain, lots of morning traffic, and I had warm coffee and the radio to keep me company.  I opted to bypass all the initial DCQC stations, and after driving 118 miles arrived at the Atwater DCQC with 29% battery capacity remaining (about 10 kWh)  – more than enough to reach my destination.  But, because of the heavy traffic it took me over 2½ hours to drive that distance.  And even though I was only 15 miles from Merced, after drinking all that coffee I really needed to stop so I could go.

Many DCFC stations are conveniently located near stores and places to eat.

Many DCFC stations are conveniently located near stores and places to eat.

I plugged in the CHAdeMO cord, and while charging for 30 minutes (the grey area on the charts), I stretched my legs and found a coffee shop where I could get a bite to eat and reload my travel mug with fresh coffee.

That 30 minute charge stop brought my battery state of charge up to 76%, giving me over 100 miles of range.  That was enough to visit my colleagues in Merced, and then drive to the Salida DCQC station on my way home, with plenty of extra to spare.

The charge stop on the way home got me up to 83% SOC, giving me enough driving range to drive the 80 miles home and arrive with about 10 kWh remaining in the battery pack.  The whole trip had been 265 miles and it was just plain simple.

I could have made the same trip using Level 2 charging.  The nrg DCQC station in Atwater also has Level 2 charging, and there is a Chargepoint Level 2 station in Merced.  But, at a rate of 20 miles of range per hour charging, I would have needed a total of 7½ hours of charging, instead of just 60 minutes, to reach the same state of charge I got with DC rapid charging.

Level 2 charging will serve the bulk of my charging needs for my day to day routine.  But being able to rapidly charge my car when needed is a huge improvement.  Increasing the number of DCQC stations will undoubtedly increase the number of people and businesses using electric cars for travel.  The State of California needs to fully get on board with DCQC and complete the West Coast Electric Highway, and open charging corridors along heavily traveled routes.  The ability to branch out, to drive further and quickly reach new destinations – powered by cleaner, domestically produced energy – has opened new horizons for me.  If you haven’t driven an electric car yet, take one for a test drive and I’ll see you on the Electric Highway.

Disclaimer: The author has no financial ties or connections with companies and organizations mentioned in this article.


Want to keep up with the latest news in evolving transport? Don’t forget to follow Transport Evolved on Twitter, like us on Facebook and G+, and subscribe to our YouTube channel.

You can also support us directly as a monthly supporting member by visiting

Share on FacebookTweet about this on TwitterShare on Google+Share on LinkedInDigg thisShare on RedditEmail this to someonePin on Pinterest

Related News

  • Mark Gemmell

    Thanks Stephen. Nice article that gives a clear message about the need for higher power charge solutions for road trips. You mention you used a MyCarma… I get the feeling they are not in business anymore. How/when did you get yours and do you know anything about them now?

    • Stephen Noctor

      No hadn’t heard that. I got it within the last year. Don’t remember the exact day. As of a several days ago their data servers are still up and running…. that’s where I pulled the SOC data etc for this article. I’ll have to check and see what’s going on…..

      • Mark Gemmell

        I contacted Matt, their CEO, and they are still around. I think I jumped to the wrong conclusion there. 🙂 I’d like to get one of their devices so with any luck they’ll sort out some tech issues they seem to be having and I’ll get one soon.

    • Dennis Pascual

      As you figured out below, they are still around (their focus is on fleet management) and their MyEV product is nice. However, it depends on what EV you are using. I bought one for a Model S and another for a Roadster. The Model S worked, but the Roadster didn’t, so they refunded me for both. (I bought both to be able to have “friendly competition” with my better half on how we drive our EVs.) The team at MyCarma gave it a good try and I spent a bunch of time with them to try to figure out the Roadster stuff, but to no avail. Good customer service

  • vdiv

    Why not plug in every night and wake up with a full (80-90%) battery in case your routine is interrupted a bit?

    Also in your trip scenario with L2 charging, ostensibly you spent some time at your destination. Presumably you could have charged there and started the trip back with a full battery and reducing the L2 charging time during the trip.

    • TonyWilliamsSanDiego

      I did not read in the article anything that suggested that the author did not charge overnight at his home, as you suggest. He started with a full charge, presumably from his home, for this trip.

      In addition, since this issue comes up a lot with EV discussions, more than 50% of the population does not live in privately owned homes. For them, it may be that public quick charging is the only option with EV use.

      We don’t know that any electricity was available for EV use at the author’s destination, or that he spent enough time at the destination to get any measurable increase in stored energy. In my quite extensive travels in EVs, finding power for an EV at my destinations is the exception, not the rule.

      Disclaimer: our company, Quick Charge Power LLC, provided the equipment for the author’s 2012-2014 Toyota RAV4 EV that allowed for public DC quick charging. We are now working on the Tesla Roadster, Mercedes B-Class ED, and Ford Focus Electric.

      • Mark Gemmell

        I want to hear about that Roadster option!! Add me to your customer list please. 🙂

        But how do you convince a car that is built for only AC to take DC? It surely must require some changes behind the scenes in the car itself?

        • TonyWilliamsSanDiego

          Mark, we will figure out the details. Send me an email at:

          TonyWilliams (((@))) QuickChargePower (((daught))) com

      • vdiv

        1. If you look at the home charging diagram he does not charge Monday night and Wednesday night. The diagram description says he charges every other day. He also states that he charges overnight at home in his garage while he is sleeping.

        2. Absolutely! Also people have cars in order to be at places other than home.

        3. Hence “presumably”.

        Disclaimer: I am an AC charging proponent and though now I benefit from fast DC charging I have strong reservations about it.

        • TonyWilliamsSanDiego

          I’m an AC charging proponent, too… it works great at night for folks who have availability to electrical power near their overnight parking location. As stated, that might be roughly half the population. AC charging also works great at a work place, also, for those folks who drive to a work place that has such capabilities. That identifies far less than half the population.

          I’m also a DC charging proponent. After traveling 12,000 miles in my Tesla Model S in the past month, coast to coast, and north to south, I can assure you that it would not have been possible without the extremely well done Tesla Supercharger (DC) network. My total out of pocket expenses for transportation energy for the entire trip was $15; $10 at a hotel in Buffalo, New York, and $5 at a campground in Great Falls, Montana.

          I don’t own gasoline powered cars, so when you next suggest that the trip would be better / cheaper / faster / etc with a petroleum powered car, let’s just say that I disagree in advance. Since the trip could not have reasonably been done without DC charging, certainly folks who have “reservations” about DC charging are a real head scratcher.

          • vdiv

            When I next suggest… I’m sorry, what?!

            I understand that you are trying to sell your JdeMO adapter and I applaud you for making it. My beef is with the infrastructure and the approach to charging.

            The 130-mile one-way trip could have been done in a 100+ mile EV with L2 30A AC charging without much effort. The definition of reasonable remains subjective. 🙂

            In terms of having DC reservations, the reliability and cost track record of the infrastructure can be much improved. Nearly half of the stations deployed in the Mid-Atlantic were out of commission at one point last winter with eVgo unable to get the parts and fix the stations. When you have a single station per location that puts quite a damper on long trips planned on DC charging.

            If we had 3-phase charging and vehicles like the Zoe that would charge at 43 kW AC none of the current crop of CHAdeMO and CCS stations would make any sense. Even with 80A J1772 stations that are finally slowly making their way, allowing for 60 mph AC charging is nothing to frown upon. These stations are still multiple times cheaper to install and operate.

          • Stephen Noctor

            But let’s remember, that would be the case IF I had the time to stay for at least 6 hours at my destination, which I didn’t. And then if I needed to add range on the way back, which would have been likely, IF I had time to stop for about an hour. For folks in business, time is money.

            >”The 130-mile one-way trip could have been done in a 100+ mile EV with L2 30A AC charging without much >effort.”

            As for the 80 amps, only the Teslas can handle that. The Rav, the Mercedes B class are limited to 40 amps. Others correct me if I’ve left something out, but just about everything else currently on the road is limited to 30-32 amps, 7.4 kW and lower.

            Many of us agree on the need for reliable high power chargers. We agree that 6 or 7 kW is fine for most day to day driving while using overnight / worktime charging. But when we start branching out with trips over 100 miles, toward 150 or more, higher power will increase adoption IMO. Yesterday I met a guy at the CHAdeMO station in Vacaville who uses a BWM i3 BEV for his business. Said he drives 200 miles a day. The current DCQC stations make that possible for him. Improvements are of course always good. Tony’s solution for the Rav greatly increases utility. Hopefully some day in the future we can all charge at 100kW or more, but for now 40+ kW is a big step.

          • TonyWilliamsSanDiego

            Ok, so you’re not against DC charging. You’re against broken chargers. That’s reasonable.

            You’re not going to get three phase AC in a country that largely doesn’t have widespread three phase power. Sorry.

          • vdiv

            I’m sorry too because there is widespread 3-phase power, all of the DCFC stations and many of the existing public L2 stations (207V) are powered by it.

    • Stephen Noctor

      It’s in the article. As mentioned in the article, I could have used L2 in Merced. The comparison here is total time required for charging and driving on DC versus L2. I would have needed 7 and a half hours on L2 to reach the same SOC that I got in 60 minutes on CHAdeMO. What I didn’t mention is that there are currently only two Level 2 charging stations in Merced (and one 110V outlet). I arrived and a Leaf plugged in. There was also a Spark and Focus EV in the lot. Would have really sucked if I needed that charger (for at least 6 hours) and it was occupied. Chance I’m not willing to take. The Merced chargers are on the Chargepoint network and cost $2 an hour for the first 3 hours, and $5 an hour after that. I would have spent over $20 bucks to charge up, in this case it was cheaper and of course way faster on EVGO. For L2 I would have had to stay much longer than I wanted. Oh, and there is also a practically useless (for a Rav) 110V outlet that costs $6 to use.

      • vdiv

        Thanks for the clarification. So apparently Merced is not exactly a charging bonanza. The East Coast EV drivers imagine all of California as one giant charging station 🙂

  • David Galvan

    I learned early on to filter out all the level 2 stations on my PlugShare app, and ONLY consider QuickCharge stations.

    As you verify with your plots, the Quickchargers can charge my Leaf 7x-8x faster than a Level 2 charger. If I’m having to stop my drive to charge back up, why in the world would I choose a Level 2 station if a QC was available?

    I realize a 480V quickcharge station has different requirements and is more costly than a 240V station, but I think the industry should concentrate on more DC Quickchargers in public places.

    Level 2 stations are appropriate for workplace and home charging (as well, possibly, as restaurants and movie theaters), since the car sits in the same place for several hours at a time.

    But most public stations (shopping malls, grocery stores, rest stops) should be DC QC.

    • Carney3

      Level 1 is OK for long term airport parking lots, since cars stay there for days or weeks.

      Level 2 works for sports stadiums, amusement parks, other resort like destinations (parks, beaches, ski areas) – places people tend to stay in or at for 3-4 hours or more.

      DCFC for convenience stores, big box stores, fast food, etc.

      I think sit down restaurants and malls are in a gray area between level 2 and DCFC.

      If you’re a restaurant owner, while table turnover rate is important, it’s probably going to take longer than 20-30 minutes of DCFC charge time to maximize revenue from a single customer let alone a family or other party, counting appetizers, main course, desserts, drinks, etc. You might not want to hustle a party out the door too fast with a “charge done” ding on their smartphone if you can milk them a bit for more coffee.

      Same deal with malls. Some people run in and out to buy something specific. Others spend an entire morning or afternoon, browsing at leisure.

      Hotels I think are a gray area between level 1 and level 2. You want to be able to get them to go from empty to full overnight, but level 1 might be able to do that for most, and the installation cost of level 2 is a lot higher. “No-tell motels” are of course a whole different story…

  • BenBrownEA

    Some one asked me why aren’t all public chargers DCQC…

    Costs. Running electrical lines, equipment, maintenance, etc.
    In Michigan they keep saying we don’t need dozens of DCQC to travel between cities, We need them all in one or two of the largest cities (actually they are going with one city) as no one wants to travels between cities with an electric car. So that is what our grant is currently being written for. Your example brings into question whether ev’s are limited to city boundaries. That is why I LOVE what you wrote.

    Myself, I drive between cities, but have had a 7+ plus hour waits simply charging. Within cities I find L2 (along with home charging) meets 100% of my needs without needing to wait. 100%!!! – while I’m shopping, eating, seeing movies or at the library. It may be the i-miev is far far more efficient than other ev’s, but I doubt that. I think it is more planning.

    Intercity driving DCQC would be a dream come true.

    Judicious placement of DCQC would cause a increase in ev adoption in Michigan. Likewise there is the arguement that a DCQC on every block in the city would increase the purchase and use of ev’s. But I can’t help but go back to, if people planned they would find L1 and L2 were more than sufficient. EV’s are not gasoline fueled vehicles, they can “refuel” while they are sitting. When sitting is resource wise/practical and when it is not requires thought. I’m not sure if car makers really want that and it feels like they are loading the dice to influence how ev’s are seen and used for now. That is what it feels like to me at this moment. Could current ev’s be intercity worthy with DCQC or is it better to put DCQC all in one spot and require any practical electric intercity driving be done in a Tesla for the near term.

    • Stephen Noctor

      In my opinion we definitely need the DCQC chargers between cities if those cities are more than 50 or 60 miles apart. Limiting EVs to city boundaries will limit EV adoption. We can’t all afford a Tesla, and since many of the EVs on the market can be purchased with a DCQC port, DCQC chargers extend range and utility of those cars. Washington and Oregon have done a nice job of setting up charging corridors with DC fast charging stations located every 25 to 50 miles along Interstate 5 and other major roadways in the Pacific Northwest. That’s the way to go!

    • “Costs. Running electrical lines, equipment, maintenance, etc.”

      Don’t fall into the trap of comparing them on a charger-by-charger basis. Fast chargers are cheaper, because you need a lot less of them to serve the same amount of cars. And when properly constructed (like the Fastned stations in The Netherlands) there is no problem of ICEing.