Driving an electric car — A 200+ day field test
Update: Due to recent fatal accident of a Model S driver I felt the need to update the “Autopilot” segment to clarify a few statements.
It has been about 2 years ago, when I got the chance to drive my first electric vehicle. A new Tesla Service Center opened nearby and just for fun I applied for a test-drive.
I was surprised how easy it was to make an appointment. All I had to do was fill out the online form and a day later a sales rep contacted me. A week later I was driving the 421hp Tesla Model S P85.
So for everybody who is not familiar with the brand: Model S is the line of luxury sedans, built by Elon Musk’s Tesla Motors, Inc. P85 stands for the Performance model with an 85kWh battery. More to what that really means later on, but suffice to say it gives you an estimated NEDC range of 502 kilometers on a full battery. This was the top-of-the-line configuration available back then and with a price tag of around €120,000 certainly not a cheap car.
My second surprise was, that they let me drive the car, even though I made it clear, that I have no intention of buying it. They showed me some other (cheaper) configuration options and emphasized the reduced running cost of an EV, but that was the full extend of sales talk they gave me. Back then I was driving a Prius, which is a very efficient car, so most of the talking points did not seem like all that big of an advantage.
The overall experience was really nice and it certainly left a lasting impression. I’m normally not interested in cars (besides watching the occasional episode of TopGear), but for a tech-nerd like me, this brand is so refreshingly different, that it peaked my interest and I kept following Tesla ever since.
So in October 2014 this happened:
That “something else” was probably the thing that most intrigued me about the new version: The Autopilot! In case you live under a rock and don’t know what that is, here’s Elon Musk explaining it:
So after I made a second test-drive last year it seemed to me that Tesla added all the little features I thought were missing in the P85:
- Proper driver-assistance you’d expect for a car of that price range.
- A cheaper 70D option with reasonable range and Supercharger support.
- GPS automatically routes via superchargers on long distance drives.
- New color options (especially a new and more vibrant blue).
The rumor, the prices will increase due to the exchange rate between Dollar and Euro, was the last motivation. I clicked the “Order” button in my online Tesla account.
Preparing for the Revolution
To jump a ahead a bit: Can I recommend buying an electric car? Yes, if you have the right mindset for it. Driving an EV means, first and foremost, planning ahead of time.
So before you buy an EV, you better know exactly:
- What is the typical range of your car?
- Where can you charge it (at home, at work, public charging stations)?
- How much does that cost, and is it an improvement over what you have now?
- Are you willing to pay the premium for the benefits?
- How much time can you spend charging?
- How much time does it need to charge?
- Are you planning long-distance trips? If so, is that feasible with the car you have in mind?
It’s not like buying a gasoline car doesn’t come with some things to consider, but these questions are not always easy to answer. Furthermore you should (and will) learn a lot about currents, voltages, energy, and power. The biggest insight I gained was: EVs don’t charge that long because the Batteries are that slow. They charge that long because most sources of electricity simply cannot handle any more.
The Basics
Lesson number one is: Your ordinary wall-plug is useless. The math here is simple: In Germany you can pull about 13Amps from a 230V outlet. That is 3kW in power. My Model S can hold 85kWh, which is a unit of energy. That means the battery can yield a power of 1kW (or 1.35 horsepower) for 85 hours. The other way around that means a household outlet, which can deliver three times that power, needs about 30 hours for a full charge. Other countries have even less power on regular outlets, so depending on the length of your regular commute, a night’s worth of charging might not even be enough to cover your daily energy usage.
What you really need is a high voltage outlet. These can put out up to 11kW (or even 22kW) of power. Most public charging stations are equipped with that. But here comes the second limitation: The battery in your car requires direct current (DC) to be charged, but electric grids only deliver alternating current (AC). So your car has to be equipped with an AC/DC converter. By default, the converter in the Model S works up to 11kW (or 16 Amps). You can pay extra for a double charger, which allows you to use 22kW… but this is as far as it goes. At this rate you’ll still need 4 hours for a full charge, a bit more on the 90kWh model. If you can charge with direct current, much faster charging speeds are possible. Much, much faster…
Tesla’s Genius Move
With these charging times in mind, long distance travel is almost out of the question. This is, quite simply, the reason, why EVs are not widely accepted yet. There is no incentive to provide better infrastructure (too few cars) and nobody buys the cars, because there is no infrastructure. A catch-22.
The guys at Tesla knew, if we don’t built the infrastructure, nobody will. And so they did. They built a network of Superchargers. Each one of these chargers puts out a staggering amount of power, far beyond what a normal AC-outlet can do. At peak output, a Supercharger delivers a whopping 135kW.
This means in theory it is able to deliver a full charge in less than an hour. In reality the speed depends on how full the battery already is. It takes longer to add 5kWh to a almost full battery than it takes on a fairly empty one. So if you do a little bit of planning, and make your stop at available (and strategically placed) Superchargers you hardly notice the waiting time. Most likely you would have done a stop anyway (for a coffee and restroom break). The range of the Model S is big enough to easily reach the next Supercharger in most of northern and western Europe and the US, which gives you an incredible amount of covered ground.
Crunching the Numbers
So I did all the math, and for me it was the right choice. I don’t charge at home, but I have public charging stations nearby, where I can do a full charge for free or a flat fee of €3.30. If they ever plan to increase that amount, I can charge at work or close by, if I want. IKEA has free parking with an 11kW charging port. So why shouldn’t I use that? On top of that (although I didn’t know that when I signed the lease), a Supercharger opened right next to my office. Using these for day-to-day charging is frowned upon, though, so I only use that in urgent cases.
I travel long distance rarely enough, that the extra bit of waiting at the Supercharger and the tour planning is not much of a downside for me. My commute is a bit more than 25km each way so range usually is not an issue. An overnight charge every week or so is enough to keep me running.
The First Few Weeks
It is hard to describe what it feels like to switch from a gasoline car to an electric car, if you haven’t tried it yourself. The amount of torque an electric motor puts on the road is mind numbing. And I’m not just talking about the Model S here. I’ve also tried a couple of other options. For example the BMW i3, although significantly less powerful, still feels like a really agile and nimble car. And with over 2 tons of weight you’d expect the Tesla to be somewhat sluggish, but boy is that car quick.
My 85D comes with 428HP, which is more than the Performance model I first tried had, but still less than the 700HP of the literally “ludacris” P90D. The benefit of an electric motor is, that it can apply that power right from the start, pushing you into your seat in a fashion you only experience in a supercar or a rollercoaster. The low center of gravity and the all wheel drive let you forget that you drive around a car with the weight of a young elephant. It is, quite simply fun… a lot of fun!
The Commute
One of the primary motivators for getting a new car was the immense dissatisfaction with my daily commute. I have to drive an acceptable 25km each way, but there is quite a steep hill in the middle of it. So basically it’s 10km uphill, 10km downhill. In an under-motorized car that means listening to loud engine noise a good part of the way. The way back usually gets me stuck in traffic. Driving in a jam always exhausts me, because you always have to be vigilant to the car in front of you, adjust your speed, stop, phase out and repeat. Normal cruise control is of little to no help in that situation and waiting in traffic is, worst of all, wasted time.
Model S had a huge impact on that. It breezes through the uphill climb with power to spare and uses the downhill drive to recharge the battery. The Traffic Aware Cruise Control (TACC) adjusts to slow moving traffic so you can relax quite a bit. After the introduction of Autopilot, I can even do actual work, when I’m stuck in traffic (see “Autopilot”).
I’m not overstating, when I say, that my Model S has improved my quality of life significantly just for these simple changes. I spend over 5 hours a week commuting. That is over 10 days a year just for that. Making that just a little bit more convenient, is a huge game changer.
Now, Tesla isn’t the only manufacturer who has a car that might have produced a similar effect. But it seems that right now it is the best one.
The Autopilot
Okay, I admit it. The Autopilot was the primary reason I got a Model S. There is no question, that wouldn’t that have been introduced, I most likely would have bought a hybrid again and financially that would have been the smarter choice. There is no way arguing around that.
But that reminds me of a similar situation, although the scales were considerably different back then: The introduction of the iPhone. It’s hard to remember the cell-phone market back then, but the iPhone was a lot more expensive than your regular cell-phone, its functionality was somewhat limited and today we know, that they had to cut quite a few corners to make it even work. But nobody cared, because the concept was revolutionary and ahead of its time. It felt like being catapulted into the future, and that is exactly what it feels like to drive around a Tesla. Or rather, let the Tesla drive you around.
Using Autopilot was scary at first. I was probably more on edge while using it, then I was while driving myself. It still made quite a few mistakes and I didn’t have any experience, when it might fail and what would happen in those cases. I even had, no kidding, nightmares about my car taking over control and me losing the ability to get it back.
But the Autopilot learned, and I gained experience. Now I activate Autopilot whenever I can, and where it is running reliably. That is, by gut estimate, about 60–70% of my mileage. I intervene, when I need it (mostly because of lange changes, ramps and speed limits), but most of the time I actually spend concentrating on traffic. More than I ever did before. I am now more aware of the cars next to me, behind me, in front of me and way ahead of me. Things I was not really able to do, since I had to make sure, that I don’t slam into the car right in front of me. Now I feel a bit like a driving instructor, watching over a student. You still need to have some awareness of what’s going on, but you can relax most of the way, because you can trust the student to at least take care of the basics.
And then there are the situations, where I trust the car almost a hundred percent. And this is where I think the lawmakers will have some work cut out for them: Because often I stop constantly monitoring the car and I phase out. And yes… I do write texts, while I let Autopilot drive. Is that illegal? Most likely yes, but the more I use Autopilot I start to think it shouldn’t be (in certain situations) *.
I would go even further. I think in many situations (if not most), Autopilot is a better driver than I am. It sees in the dark (through radar and sonar), it has sub-microsecond reflexes, it doesn’t get tired, it has eyes in the back and it is only getting better with age. I can recount at least two instances, where Autopilot has saved my bacon, from situations that might have gone terribly wrong, otherwise.
In conclusion, Autopilot is a revolution. Just as the iPhone was back when it was revealed. It still has its flaws, but I have no doubt, that this is what the future looks like. And I am already part of that future, which is quite a cool feeling.
*) Note: I want to clarify here, that I do not talk about texting while driving 150km/h in dense traffic. Of course you should use common sense! This much trust I only invest in the car, when I’m in slow traffic or in stop and go situations. Not only is the reliability in these cases close to 100% and (likely more reliable than any human), but also any crash would result in not much more than a fender bender. Also I would never use Autopilot (without monitoring) on roads, that have cross sections. Autopilot is as of yet incapable of detecting “Stop” signs or red lights. Furthermore it would most likely only detect a car that disregards the right of way, when it crosses the own lane, but then it might be too late to react.
Also I’d like to mention, that I did not expect Autopilot to be perfect, and neither should you. The only metric that counts is, whether it is better than the average human driver. And so far that is the case by a significant margin. But there’s people who did a better job than me, making that case:
Range anxiety
Every owner of an EV knows this: The feeling of dread, when your estimated range gets smaller and smaller and the next charging station just wont get any nearer. This is what range anxiety is all about: The fear of getting stuck somewhere.
This is by no means a feeling exclusive to EV owners. The most vivid memory I have of that feeling, was when I drove from the Yosemite Valley to Las Vegas. Choosing the scenic route I went via the Nevada Route 95, right through the desert. I chose to skip the fuel station after the Sierra Nevada, since I had two thirds of fuel left in my tank, and boy was that a mistake. For what felt like several hundred miles there was no gas station to be seen. So, being in a foreign country, with a rental car and an empty tank in the middle of the desert wasn’t necessarily appealing. Long story short: I reached a gas station with little more than hot fumes in the tank, but I made it. But this was easily the most stressful road trip I’ve ever taken. So range anxiety usually is the result of not being prepared. Driving a gasoline car, in my opinion, makes you actually more likely to be underprepared, simply because you’d expect a gas station to be nearby at all times. So when that is not the case is, when you really get into trouble.
So here are three experiences I had, where range anxiety became an actual problem. Each time I was badly prepared and each time I learned:
The Unexpected Errand
This was the first time I came close to the range limit. My girlfriend and I chose to spend a day at a thermal spring close by. With the estimated range of 100km we could have made it easily there and back. Also there was a charging station at the spa. I had no idea that this day I might get a problem.
Charging was free there, but the spa owners wanted a €20 cash deposit for the RFID-Card to activate the charger. Since I had no cash on me and I had enough range to get back with a couple of kilometers to spare, I thought: “Why bother?”
So when the call came from the babysitter that we need to get my girlfriend’s son a.s.a.p. I was in trouble. Because that extra trip was just about the distance I had available, give or take a few meters. On the ride back I saw the estimated-charge-at-destination gauge change from 0% to -1%. Luckily I had not yet sold my Prius around that time, so I decided to drive home, charge the car and use the Prius for the rest of the trip. Ironically, there was practically no fuel left in the tank, and I almost didn’t make it in time, with the gasoline car either!
Lesson Learned: Always go on longer distance trips with a near full battery and try to have at least 100km range left, when you reach home. You never know, when you suddenly need to go on an emergency errand!
The Underestimated Consumption
Essentially there are two acceptable routes to get from here to Luxembourg. One has two Superchargers on the way, the other has a single one on route.
With a rated range of over 400km and a Supercharger conveniently placed there is no way this can go wrong, right? Well, this is where bad weather comes into play. It was pretty cold that day and there is little that affects range as much as that. On the way to Luxembourg I chose the safe route over Nancy. The Supercharger was closer and I was able to skip the one in Metz. On the way back I chose the Metz/Strasbourg route. Since on the way up one charging stop was enough, I thought on the way back the same would apply. But by that time it was night and below freezing, and the estimated range kept decreasing. Somewhere near Strasbourg I got the message to drive below 100km/h to reach destination. Then it said no more than 80km/h. This is when it got scary. I even turned off the heater to reduce energy consumption, but to no avail.
The solution was to take the slight detour over Achern and charge enough to get home from there. I only stayed for a couple of minutes… just enough to reach home. Which I did… with 13km left. Whew!
Lesson Learned: You cannot always trust the rated range. Especially not in winter, when the cold reduces the battery efficiency and the heating consumes extra energy. Also it is better to wait an extra 5min at a Supercharger than to sweat for two hours in fear of not reaching the next one!
The Unknown Terrain
During my last vacation I had a different kind of range anxiety. It wasn’t that immediate fear of running out of juice, but more like the fuzzy feeling of not knowing where I can charge my car. I was under the assumption that I would be able to charge the car at the vacation home, since it surely will have electricity, right? Well, the problem was, that the closest accessible parking lot was just a bit too far away for my longest extension cord.
The second option would have been to charge at the next public charging station. But that required a proprietary keycard to use, which you could get for free, but during the easter holidays the office was closed.
Now, I had still plenty of charge left in the car, but the past experiences had taught me to think of the unexpected. The solution was to ask at the camping ground nearby, if I could use an outlet of theirs, because: where do you find more power-outlets close to parking lots? They we’re very friendly and interested in the technology, so it was a really nice experience. I gave them €5 for the service, even though they haven’t asked for any money. Sometimes is just enough to ask.
The day after that our neighbor gave us the tip, that there is a small service road near our cabin and we might be able to charge the car from there. That worked quite nicely and so I was able to get the battery to 100% which was more than enough for the trip home. And this was also the first time I could make use of the all-wheel drive and air suspension, since the road was not much more than a bumpy meadow.
Lesson Learned: When you travel, make sure you get access to the local charging infrastructure for destination charging, bring a longer extension cord and maybe it’s easiest to just ask your neighbors.
Conclusion
Given the choice (and the same circumstances) I would choose the Model S again. Not because it is the perfect car, but more because for me there is no other alternative on the market right now.
It seems unlikely that I will ever go back to a gasoline car. The driving experience of an EV is so much superior to everything else I’ve experienced before. And right now, the other electric cars on the market are just not practical enough. There is no question, though, that this is about to change. A bit more than a week ago the Tesla opened reservations for the Model 3 and after two minutes of hesitation I drove to the next Service Center and put my name on the list. The idea of a car with features like the Model S in a more affordable price segment is just too appealing.
Now a couple of days later, Tesla has over 330,000 orders for the Model 3, which is a small revolution.
I’m sure all the other manufacturers will follow suit (BMW i5 anyone?). Not to mention whatever Apple is working on — or not… who knows?
And to use my earlier metaphor: Just as with smart phones, in a few years we will look back and wonder, how we were able to live without this kind of technology.
