So I run a luxury car rental company and one of the most common questions I get from folks these days (especially those in the tech community) is: "When are you guys getting a Tesla?"
This article is _exactly_ why we're not getting one for the fleet anytime soon, and it's basically the answer I've been giving people since the Roadster came out (and the questions started).
Tesla is an awesome, awesome company. I'm a fan. I'm thinking of getting a Model S for myself. I think (and hope) they're going to be huge.
But they're not ready for the truly mass-market quite yet - and car rental customer (even luxury car rental customers) are the mass market.
I could see the exact scenario outlined in the article happening to renters constantly - except for one difference: We would be yelled at by the customers, not Tesla ;) ("Why is my car saying 'battery dead'? I did nothing wrong. Send a truck to pick me up or I'm writing a bad review about you guys.") Sigh.
Anyway, I'm still a fan despite the headaches - and I know they'll grow out of it.
Luxury car rental company? Please tell me more (like do you have a website??)
I ask because I know of a couple of luxury car rental companies, but there is one ore more things about each of them that make them exceedingly unpleasant to deal with. I would be interested to try doing business with a luxury car rental company that is run by people who also read HN - seems to be a good signal for not-totally-fucked-up business practices.
The car works great when it isn't cold. If the mileage estimates aren't taking temperature into account, that seems like something Tesla should be addressing in software.
A relative gauge or percentage would be one thing, but if you tell the driver it's going to get 100 miles, they need to know it can make that to the next charging station.
From what I can glean from the article, it may not be possible to completely address the problem in software, because weather prediction is inexact, and it's hard to account for all eventualities. The software can say, "100 miles of range unless the temperature drops more than 5 degrees from forecast, or unless it turns out your hotel has no indoor parking, or if you have to stay late at work and your car spends an extra four hours outside, or your flight is cancelled and your car spends an extra day at the airport." That's not to say it can't be improved, though.
That is sort of what I was wondering but recognize such systems are tricky given the feedback. Also turning electricity into heat is hugely inefficient on cold drives, if I were Tesla I would consider a 'cold weather' kith where you could put a bottle of propane in the trunk or something which could run a catalytic heater without consuming any battery power except for recirculating fans.
I was thinking of software only solutions, but I think a hardware fix may be best.
I wonder if Tesla chose to optimize for other scenarios in the design of the car: Tesla distributes the battery across the entire body, which makes for great handling, fault tolerance, and safety, but may make it more difficult to insulate than in other cars, which typically just lump the battery in the back, surrounded by insulation.
An "inside" battery also takes advantage of the solar greenhouse effect from the glass-enclosed interior. On cold-but-sunny day, a parked car will heat up substantially simply due to the ~1kw/m^2 of solar energy delivered to the vehicle. Of course, you don't want the battery getting to hot, either. In addition to better thermal insulation, perhaps Tesla could add solar panels to the roof to aid in heating and cooling.
I hope this problem is solved, as it would be a bummer not to be able to take a Tesla on a ski trip.
Very worth reading if you want to know what it's like to drive a Tesla Model S on an actual road trip. The New York Times reporter John M. Broder finds out that the gauge in the Model S to estimate remaining mileage before the next charge is badly confused by temperatures below the usual temperatures in California.
I remember back when I used to have a travel-intensive job that I was flying into airports all over the United States and getting into unfamiliar models of cars rented on the corporate account. That was sometimes no fun at all. But all of those cars fit everyone's familiar mental model of displaying fuel remaining. The Tesla Model S, by contrast, reports miles still able to drive in a dynamic model that can rapidly get out of touch with reality. And of course it takes a good bit longer to fully recharge a Tesla, even with high-speed recharging, than to pump gasoline into any other kind of car. This will take some major getting used to for most drivers.
Of course an EV is going to have trouble in cold weather -- it's just physics. It's just surprising to me that so obvious a situation didn't come up in testing the software. As a resident of Toronto who was interested in the Model S, it's a bit eye-opening.
For sure. The lack of charging stations will eventually be solved, but longer charging times and unreliable readings might be with us forever. Hopefully the cost offset for fuel will make it worth it.
Regarding unreliable readings of remaining charge, I'm of two minds. Consider digital cameras, which use a similar battery chemistry. For more than a decade, Sony has for some reason been basically the only manufacturer whose cameras produce a fairly specific and reliable indication of time remaining. Maybe it's a patent thing, but my Sony prosumer camera from 2002 had a better indicator than pretty much anything not from Sony I've seen since.
I'm not saying the tesla couldn't be better or that they couldn't learn something from Sony. But part of the author's complain was that he had one reading in the evening and when the temperature dropped overnight his reading the next morning was drastically lower.
Also a while a digital camera does get to spend some time outdoors it spends most of it's life in fairly people comfortable environment.
There is no reason for unreliable reading to be with us forever, accounting for temperature and driving-style in an estimation system is non-trivial but far from impossible. It is the sort of problem that will be incrementally solved as the technology matures, Telsa themselves will learn from their more northerly deployments.
Gas stations are incredibly common. Public EV charging stations will never be as common unless a different business model is adopted.
If EVs become common, people will have home charging stations. Demand for non-at-home charging stations will come from (1) folks who drive a lot and need to charge intraday (and who cannot charge at work) and (2) road trippers. The sum of both of these categories is fairly small and less demand means less supply. So if you do fit into one of those two categories, you will need to plan your driving carefully instead of figuring that you'll be able to pick up some gas when you need it. This can be overcome by arranging for the proliferation of public EV charging stations even absent the demand. Perhaps the manufacturer or municipalities will subsidize it.
Making people sit and wait for an hour whenever they need to recharge is just plain nuts. It makes the "road tripper" use case untenable. The right way to handle this for road trippers is to swap the battery packs or swap their contents. Don't make the driver wait while his battery is recharged - swap in a full pack and send him on his way. Charge the battery that was left behind slowly and at leisure, then give it to the next driver who pulls in needing a charge.
I don't care how many charging stations there are - adding multiple hours of charging time to a short trip like that is just not going to work.
Although there's one other conceivable option for a technical solution - if you could add charging circuitry to the freeway and recharge while driving, that would be a game-changer.
I agree with you that this is the only realistic mainstream future of electric vehicles as long as batteries remain in their current low-density state.
If swapping is the answer then in that case you need a non-ownership model for batteries. I am not going to swap out a brand-new battery for a 2 year old one and then be stuck with that one for the foreseeable future on my regular local car use.
I think what will happen is that people will all own EVs and then rent gas cars for long distance trips until there is some huge breakthrough in battery capacity or charging times.
As a fan of Tesla's efforts, it pains me to read this; no matter where the blame lies (physics, bad planning, poorly tested diagnostics software) this article will haunt the company for years. Every oil lobbyist will eat this up, and it should become the foundation of any EV-haters argument.
And that sucks.
However, I'm annoyed that Tesla's UX people let a car with this much design intelligence leave without connecting range estimations to a simple thermometer.
I understand that to HN readers batteries in the cold is "simple physics" but if the battery indicator jumps around like a BitTorrent download time estimation, people will quickly learn to not trust what the car tells them.
Consumers that are highly neurotic about the road trip problem are much more likely to remember these sorts of horror stories when making a purchasing decision.
It's going to haunt not just Tesla for years, but all electric vehicles. And with good reason - calculating the remaining potential energy of Lithium batteries is difficult, even without throwing in the variable of temperature. It is not, by any means, "simple physics". The battery is a weak point in all EVs right now, and not just because of this.
Full disclosure, I own a Zero motorcycle. The thing is amazing in SF city traffic. It's less amazing on the highway. You should read up on Terry Hershner. He's taken a Zero motorcycle cross country by driving for 45 minutes and charging for 45 minutes. So, it can be done, but road trips are not the optimal use case for an electric vehicle. yet. :)
But if I read the article right, the car IS adjusting its display for temperature. When the temp went down, the calculated available miles went down also -- and almost accurately, that is, the car went dead about when the miles-left display went to zero.
The question I'd have is, how much current would they have to divert to keep the batteries warm? It seems like the juice expended to hold the battery pack at 20C might be less than the capacity lost by letting the batteries go down to an ambient -5C.
Or, they could provide what a lot of east-coast cars have, a built in engine-block heater that you plug in to a 110V extension cord overnight. Except in this case it would be a battery pack warmer, but the same idea, keep the important bits toasty over a cold night.
When the temp went down, the calculated available miles went down also -- and almost accurately, that is, the car went dead about when the miles-left display went to zero.
Showing that the range is zero when the battery is dead is not hard. The problem is when the displayed range drops faster than you're traveling, and if that wasn't the problem, he wouldn't have been stranded. If it was adjusting its display for temperature, it wouldn't have been wrong.
Or, they could provide what a lot of east-coast cars have, a built in engine-block heater that you plug in to a 110V extension cord overnight.
Had he plugged the car into a 110V outlet overnight, the battery would have been charged in the morning.
My friends think I'm dowdy. Until recent years, I was very conservative about estimates. Every "event" in a trip adds 5 minutes, no matter how "nothing" it seems. I was often too early, but never late.
A Tesla S with the 260 mile battery, I would treat like a car with 130 miles range. Plenty for an around town commuter and errand vehicle. A Leaf, I would treat like a 50 mile range car.
Also, why don't those things come with a propane heater? Electric heat makes no sense.
Having to put a propane heater into a shiny, high-tech electric car would be a marketing disaster: it would emphasize that battery capacity was something that drivers have to worry about under normal driving conditions. Plus, Tesla could no longer claim that their car had zero CO2 emissions.
> Having to put a propane heater into a shiny, high-tech electric car would be a marketing disaster: it would emphasize that battery capacity was something that drivers have to worry about under normal driving conditions.
Battery capacity is, though, just like it is something you think about when driving a petro fuel car. Drive a diesel? You need to think about gelling fuel in Vermont in January. For a supposedly well educated technological society, an awful lot of us seem to engage in magical thinking.
Knowing nothing about heaters, I'm curious: why does electric heat make no sense? My intuition would be that an electric heater would require far fewer components (especially considering the battery is already in place), be less dangerous, and require less maintenance. What is the relative efficiency of electric heaters to propane heaters?
Electric heat via resisters is very simple, but very inefficient. (EDIT: Thermodynamically space-heaters are 100% efficient, since they always convert their source energy into heat. They are inefficient from a monetary point-of-view.)
You can do electric heat via heat pumps, but it requires more equipment and it doesn't work if it's too cold. You can get about a 4 to 5 advantage over plain resistance heat.
Gasoline engines lose a lot of energy to waste heat -- but sometimes that waste heat is exactly what you want.
> (EDIT: Thermodynamically space-heaters are 100% efficient, since they always convert their source energy into heat. They are inefficient from a monetary point-of-view.)
I don't think they "make no sense", and I'm not sure a propane heater is the answer, but an electric heater is going to require the use of battery power otherwise used for getting you from point A to point B.
This blog post states the obvious: early adopters better know what they're in for and what they're doing. The author isn't an experienced early adopter and doesn't know what they're doing, and rightly concludes that the technology isn't ready for universal mainstream use. Unfortunately, the article entirely fails to address the point and is aimed squarely at an audience that won't get it either. It will be used as ammunition against electric vehicles for months. This subtle, yet thorough, misrepresentation is irresponsible and quite annoying.
The article seemed totally fair to me. I'm not sure how you can conclude that the author is not an experienced early adopter and am also not sure how relevant that is when discussing a new automobile on the market. What was mis-represented? How is the article irresponsible?
The Tesla isn't just a "new car" - it's new technology. It doesn't have the years of accumulated wisdom and infrastructure that support normal new cars. The same way that you understand that cold weather means you have to let your car warm up before you can drive off, it will be common knowledge that electric vehicles lose a quarter or a half of their range in cold weather. This article will be completely obsolete in a year, but because the author failed to convey that point it will sit around people's minds for years.
This article will be completely obsolete in a year, but because the owner's manual failed to convey that point it will sit around people's minds for years.
Fixed above. Also, my impression from the article is that Tesla is telling people to derate the mileage estimate by more like 10%, not 25% or 50%.
>Replace him with "an experienced early adopter." How would the article be different?
So, I've been reading the forums at teslamotorsclub.com recently, and there are a lot of questions (and answers) about the Model S's range. From what has been written over there, it sounds like the car's speed has the biggest impact on range. In the NYT piece, I notice that the only time he mentions his speed is after it started to look like he might not have enough range to make it to his destination--and then he only mentioned how slow he had to drive. I would submit, then, that an "experienced early adopter" would know that his driving speed matters and therefore not try to drive down the expressway "upside-down at mach 3 with his hair on fire."
I also notice that the author made no attempt to charge the car at his destination in Connecticut. Instead, he planed to rely exclusively upon Tesla's "Superchargers" for the entire trip. Again, an "experience early adopter" would know that the Model S can be plugged into a clothes dryer outlet and fully charged overnight (i.e., no waiting). He could have started his second day with a fully-charged battery, if he chose to. Actually, the author probably would have had enough range for the rest of his trip if he had even plugged into a standard 120V domestic outlet in Groton.
Frankly, it sounds like the author was trying to make his life difficult. Almost a third of the verbiage is devoted to range problems that were a direct result of his decision not to charge in Groton. When drivers choose not to fill up before driving across Death Valley, do we blame the driver or the car?
This isn't to say that the car is ready for prime-time. After all, the author may be representative of the general public. However, I think that anyone with even a modicum of curiosity about his new car--and more importantly, someone who, by purchasing one, had some sort of incentive to make things work instead of writing a diatribe in the NYT--would have no trouble figuring out these things, and avoiding the range problems described in the article.
The reporter was testing the car. Therefore, it makes sense to drive it to its limits. And it is totally fine. However, you should then be prepared to suffer the consequences. In this case, towing.
Frankly, I dont get all this discussion about mileage. It seems like a perfectly good car for driving in the city already, which is where most of fuel is wasted.
The problem really is the mindset (and infrastructure). People in gasoline cars regularly drive their cars to the point where they have 1/6th of fuel left and then refuel.
That is just not the modus operandi with an electric vehicle. You plug it in everywhere you can, and frankly thats almost everywhere theres main power.
I have no personal experience with this, but several forum members of the site I mentioned above have written that they have never been refused a 120V plug-in (which, again, would have been enough for the author to complete his trip--provided that it wasn't fueled by amphetamines and a mason jar). The have also written that hotel managers are often amiable to allowing 240V charging when there is an available socket.
I also just checked plugshare.com: there are at least half a dozen public J1772 charging stations (which are relatively high power) near the route segment where the author plausibly had range anxiety. Why he chose to charge at Butch's Lunchonette when there was a high power station nearby is baffling. What is doubly baffling is that he launched on a 209 road-mile trip with 185 miles of estimated range, and then made no attempt to recharge the car until he was nearly stuck (if you believe the numbers on the little map inset). So, I'm afraid that I can't escape the conclusion that this is a problem of the author's making.
He wouldn't have tried running the vehicle to the edges of its optimal-condition performance in non-optimal conditions. Or he would have been expecting trouble and reacted early enough to avoid being towed. Or, most of all, he would have emphasized in his writing that his experience is unusual and that the article will be obsolete in a year. An average consumer with one of these cars will be able to draw on years of wisdom and infrastructure that the early-adopters had to develop for them.
You could probably say the same thing for the first gasoline cars on the road or even the Model-T. I'm sure there were people saying things like "Well, if you run out of gasoline you're stuck. I can just stop at a field and let my horse eat some grass and I'm back on the road."
Early adopters in any age will have a rough time, that's kinda the definition of early adopter. However, in a hundred years people are going to be as familiar with this technology as we are with liquid fuel. They'll probably look back at us and chuckle about how primitive we were with our "battery" technology. :)
Underestimate the remaining miles. Even if that makes you look bad up front. Its an eerie form of cognitive dissonance when your reserves are dropping faster than you consumption and the wheels in your mind spin wondering "will I have enough". You never forget this feeling. Even if its just a test drive, you'll associate Tesla cars with that feeling forever after.
This is why electric cars are not magical fairies and can't solve the structural problems around transportation in the USA. They suck for long-haul travel, but nobody should have to have their own car for long-haul travel. It should be possible to travel around by train, using a rented car for only the last short leg of the trip, if it happens to be rural, or local public transport otherwise. Electrics would be just perfect hired cars if you only needed to go ten miles and back or something like that.
Is there anything to be gained by making the parking brake electrically actuated? Such parking brakes are becoming increasingly common in cars of all types and it bugs me. From an engineering perspective, it seems like it's just introducing a complex dependency that can fail to a critical part of the car.
I used to be excited about electric cars, but lately I've been wondering if it wouldn't be better to use the power source to manufacture fossil fuels using an environmental source of carbon and ship that to customers. That would make the fuel carbon neutral.
Because the world understands completely how to store and handle and deal with liquid fossil fuels.
There's also something elegant about the technology. If you compare the complexity and expense versus the energy density of a lithium-ion battery pack and a metal can, there's no comparison.
However, in an ideal world, I would think that carbon neutral hydrocarbons would become a niche fuel for things like long haul trucks and bulldozers. (And for auxiliary space heaters in people's electric cars.)
Why did the reporter have to rope Steven Chu into the article? Even if all the facts are 100% right, it seems lame to try and make this a political issue.
I know people who have done family road trips with the Tesla S already and didn't have those problems in normal weather. One could surmise that pushing the edges of the range AND pushing extreme weather conditions might be risky, and in an EV it is certainly riskier than in a gas car, but like the Top Gear "driving a roadster on a race track drains the battery horrendously", it somewhat reads like an attempt to intentionally push an EV to the breaking limit, and then write a negative article about it. The political angle of trying to make Tesla look like a Steve Chu/DoE failure increases my suspicions.
Could you imagine a reporter writing an article about a gas car that he intentionally drove at the limit of its mileage, got stuck on an interstate, and then turned around and roped in government loans to General Motors?
The Tesla S deserves criticism in order to shake out bugs and improve the software to reduce customer surprise, to better predict battery life, no doubt about that. But this should not be used by the anti-EV crusaders who have an axe to grind to score points against ex-Obama administration officials.
I agree with your comments about the politics, but I have one nitpick. 30F does not sound like extreme weather. Where I grew up, below freezing is normal for half the year. I am really curious how they are going to solve the problem of making electric vehicles work at -40F.
The weather described in that article is not extreme. It's normal. Driving at much slower speeds than traffic and not using heat in the winter is the extreme part. Cars that require extreme conditions to drive have problems.
In a rational world, every one of the gas stations he passed would have had a rack of fully charged swappable batteries, ready for installation in less time than it would have taken to fill a conventional gas tank.
Why nobody seems to understand how stupid charging an EV in real time is, is something that I find astonishing.
(To clarify: I can understand why most people don't understand why non-swappable batteries are stupid, but I can't understand why someone like Elon Musk doesn't understand that. I'll admit that it makes me wonder if I'm missing something.)
The battery for the Model S is the entire base of the car. It's over seven feet long, weighs more than half a ton and costs about $12,000 to make. I'm sure they would have loved if it could have been swappable, but getting there from the current technology would mean a lot of compromise that would almost certainly not be worth it.
Apparently -- see other comments in this thread, and the ones that were made the last time this came up in another HN story -- the Model S battery is designed as a module for rapid replacement.
Of course, without an industry-wide effort to standardize a few core battery sizes for different applications, it's a moot point. That is the problem that I wish Musk had set out to solve.
AFAIK it's designed to be replaceable without major surgery, but I don't think the replacement is meant to be quite as rapid as "stop at a gas station and they'll pop a new one in." I'm not an expert, but that was my impression.
To some extent there is a standards problem: there is not a common battery pack (like there is a gas tank fill point). But even if there were, the batteries would continue to run down after delivery (unless supplied with a non-trivial amount of power). And the space required to physically store these batteries would occupy a lot of volume. After all, gasoline/diesel is far more energy-dense than modern batteries.
But even if there were, the batteries would continue to run down after delivery (unless supplied with a non-trivial amount of power).
My thinking is that they would be kept on trickle charge at the gas station after delivery. That wouldn't take a huge amount of power. The actual recharging process would happen at a depot that has high power connectivity to the grid with low distribution losses.
I suspect it would be more efficient to do that and have the charged batteries trucked to the service stations, than it would be to have each service station do their own primary recharging. Especially since, as you say, the service station owners aren't going to want to devote a huge amount of space to battery inventory.
I'm vaguely aware of Better Place but they certainly don't get Tesla's mindshare (good, bad, or otherwise.)
Lithium-ion batteries are supposed to be pretty good as resisting self-discharge, losing only .3-.5% per day (or around 10% per month). The Tesla S has the 60 kWh or 85 kWh battery, so replacing around half a percent of that each day is 300-425 Wh. That's not much at all! If the battery replacement machines are simple and foolproof, perhaps home delivery of batteries and a small trickle charger could be a competitive model to full-blown home chargers?
Storing the batteries at the station will require much more volume than the analogous amount of gas/diesel. And a dumb tank beats a smart battery charger with software and EEPROMs if your concern is resiliency. Some EV problems are pretty clearly chicken/egg adoption problems. But there are some real infrastructure problems, too, and other changes may bear far more fruit towards the goal of more efficient energy exploitation.
The article mentioned that the top-end battery weighs in at half a ton --- not exactly hot-swapping material. Also, when it comes to safety, center of gravity, chassis rigidity, etc --- I'm sure there were a myriad of engineering decisions beyond weight that go against hot swapping. And that's not even getting to added cost and logistics of maintaining a network of skilled battery swap experts, "ownership" over the batteries (e.g. who is responsible for replacing failing units if they are shared around the community of Tesla owners).
I'm probably just scratching the surface with a minute of thought. I'm sure that the folks at Telsa have been over this ground, and much more.
You're right, those are all drawbacks. They all pale in comparison to the advantages, though.
Swapping my car's battery should be as big a deal as swapping the propane cylinder on my gas grill.
And yes, batteries these days are perfectly capable of monitoring themselves in a leased-usage scenario. Your laptop battery has its own CPU and EEPROM, for instance. To understand why, see any recent news story on the Dreamliner.
"Should" is always a tough one -- from a product design standpoint.
The tradeoffs due to price point, available technologies, time to market, etc leave a lot of "should" on the cutting floor due to compromise. I don't think we're particularly close on hot swap batteries as a stand in for real time charging while they still weigh 1000lbs.
I'm betting that folks like Telsa will drive hard on the necessary advances in battery technology over time, or energy storage technique more broadly.
Personally, I think having to swap the battery is just as stone age inefficient. I want some sort of super-capacitor with instant charge capability and fine-grained control over the energy release --- not to mention avoiding the nasty chemical mix in traditional battery tech, waste energy in the form of heat, etc.
Maybe some amalgamation of materials science, nano-tech, etc will get us there.
I actually think the major thing missing here ia not swapping out the entire pack (although that would probably be more time efficient), but having some sort of emergency pack to get you that extra 5 or 10 miles you need to a charging station (or in the case of the article, release the parking brake to quicken the towing process).
(or in the case of the article, release the parking brake to quicken the towing process).
Yes, that part of the article struck me as a real head-scratcher. This kind of "engineering" is becoming all too common in the auto industry, even among companies that have been around for decades and should know better.
For instance, the battery in the new-generation Porsche 911 is in the front trunk... which can only be opened electrically.
WTF, people? Are all the smart guys and gals working for Google these days, or something?
I actually think the major thing missing here ia not swapping out the entire pack (although that would probably be more time efficient), but having some sort of emergency pack to get you that extra 5 or 10 miles you need to a charging station.
I think you are missing something: where do you put the replaceable batteries?
Tesla's battery packs are distributed throughout the car, both to allow for cargo space (not having a trunk would be something of a minus) and to distribute the weight of all those batteries. I am having a very hard time envisioning a way to achieve both of those goals while making the batteries replaceable.
The battery pack is not distributed throughout the car, and it is actually designed to be somewhat hot-swap capable in the Model S.
It's just that for the majority of people, battery swapping makes no sense. They can charge their vehicle over night at very very cheap prices and have enough range to serve them all day. If you insist on taking a cross-country roadtrip, rent an ICE - the infrastructure is just not there yet (or peoples minds have not accomodated - see this article).
The thing you are missing is that currently, batteries are built in to the structure of the vehicle. To do otherwise would necessarily reduce the size of the battery significantly, as now the battery needs to fit in a convenient to remove location, and all the parts necessary to enable insertion/removal of the battery would take up space. Not to mention that the batteries are wickedly heavy, too heavy to be lifted by a single person, so there would need to be a machine to swap them, which takes up real estate at the gas station, and just generally complicates things.
Maybe there will be swappable batteries eventually, or one part of the battery will be swappable, but as far as I understand thats not coming soon.
Filling up a Toyota Camry with gasoline (say 15 gallons) adds about 90 pounds of fuel. A lithium-ion battery with the same energy content would weigh about 5,800 pounds. Clearly electric vehicles will have a difficult time competing with gasoline vehicles no matter how much charging times are reduced or how much better the software gets. It seems that without some breakthrough the sweet spot for battery-electric vehicles is urban driving done after charging overnight at home.
It sounds as though the problem is simply that the car loses range unexpectedly depending on the weather, so you can't necessarily count on the range you thought you had the next morning, and the degree of mile loss can be extreme. I imagine this is a problem for road trips, the occasional camping trip or overnight at a friend's house, or even when using an outdoor parking lot for eight hours (e.g. when at work or at an offsite). However, for daily commuting, it's not an issue, because presumably there is sufficient buffer if you charge every night.
What's a bit disturbing about this article isn't the laws of physics, but that he was being coached directly from Tesla. If Tesla HQ can't coach a reporter 1:1 out of a devastating result, what hope does the average early adopter have? Either the reporter twisted the facts, or the car has horrible temperature problems, or the Tesla coaches seriously screwed up.
I hope it's not a real issue. A hotel manager might be able to let one Tesla plug in overnight, but there isn't infrastructure to let ten or twenty Tesla owners do the same--yet. However, just as wifi became a competitive advantage to offer at hotels, so will EV charging stations. Perhaps even pay parking lots will begin to offer them.
Electric cars are second cars - the commuter one, not the road trip one. They currently don't make sense for road trips, absolutely. But they make a ton of sense for commuting, most likely even in cold climates.
It's an interesting and broadly relevant article, but it feels like we're having the wrong discussion - we might be single males, but the target market for the time being is well off families considering a new second car... ;)
It seems like the charge right before he stalled was the issue. I know he wasn't at a super charging station but he probably should have spent a couple of hours re-charging it instead of an hour.
Cold weather and running something that is power intensive (the heater) will drastically effect your mileage if you are relying on a battery to power your car.
Tesla probably should do a better job of communicating this but it doesn't seem like a flaw with the car.
If the battery meter can't cope with typical American temperature ranges yet it being sold in these areas, yeah, it's a flaw. If it says 100 miles left and after 10 miles now tells you 50, yeah, it's a flaw.
Can the flaw be corrected? Maybe, maybe not. But it's still a flaw.
I wouldn't call this a flaw, it happens to batteries when they are exposed to temperatures like this. The gauge for the battery is accurately trying to show you your usage in real-time.
I bet he probably could have gauged it by jumping in the car turning it on and then starting the heater as well. His mileage would have declined before he even started driving.
Think of it this way, batteries always improve in 2nd / 3rd gen devices (look at apple) and I am sure that is what Tesla will start to address.
The flaw (and it is a very major flaw) is in the reporting system, which is unable to give drivers planning their drives reliable information with which to plan their drives. That is flawed almost by definition. The reasons why are utterly irrelevant. A flawed fuel reading is a fundemental flaw in a product that is essentially useless without fuel.
If you're staying somewhere, plug it in. Even a 110V will be able to keep the battery warm enough to avoid these losses.
No, its not perfect. Neither is the choke on your motorcycle or the people in siberia waking up every 2 hours to start their combustion engines because blowing up what was generated in thousands of years refuses to happen in a cold engine block.
But I guess everyone with a modicum of knowledge has by now realized that a) we can't keep blowing up that stuff and b) there won't be another magic energy material like oil, ever again.
I just drove by some dude who was running down a pitch-dark freeway with a small child at his side. They were carrying a can of gas to refill at the station a couple miles ahead.
Damn gasoline engines - so unreliable! You'd think after 100+ years of development they'd have sorted this stuff out.
As a TSLA shareholder and as a general fan of the company, this is disappointing. TSLA's been doing everything right, which is what has given them so much momentum so early in the game, and if they are going to be the big disruptor that I'm betting on, they cannot afford to lose that momentum. If they start mis-stepping, they won't last long, and this is a misstep that many, many people at TSLA should have seen coming from many miles away.
Batteries suck in the cold. Did no one think to test the Model S in the east's freezing temperatures before they turned one over to a journalist?
There is no magic fix for this. It's like asking to turn off gravity and friction so you can have a more comfortable trip.
The reason for the big losses in the cold is the battery management system that is trying to keep the pack warm and has to expend energy to do so. You can opt not to do any battery management, but then you get thermal runaway and a life-threatening Boeing situation, or (in the cold) your battery pack is damaged.
They picked the best option there is under the circumstances.
- Have the reporting system look at current temperature and change the reported range.
- More supercharger stations closer together. (200 miles apart for a reported range of 268?! Ballsy. Especially in the extreme cold of the northeast. Reckless when you are giving a car to a NYTimes reviewer.)
- Don't have the parking brake LOCK so you can't even move the car without a flatbed truck.
- Have the car warn/inform the driver when they park somewhere cold to keep it plugged in to warm the battery up
and that's off the top of my head.
Many things can be done. This isn't necessarily a 'physics problem.' It's communicating and setting expectations. When the car says "100 miles" and you are stuck at the side of the road after 50 miles, it doesn't matter that "the physics make sense". What matters is you were screwed by completely false information.
The fix is simple. In fact, it's so simple, I would be SHOCKED if the TSLA guys aren't already including it in a future firmware update.
Even better would be to fetch the local weather forecast, and when temperatures are predicted to drop, to warn the driver and ask him to take a look at a line graph of temperature/charge as a function of time. At least that way, the driver will have an idea of what he should do.
No, they didn't. The best option would have been to test the car in real-world sub-freezing temperatures and to have worked out the bugs in how the system reports remaining charge to the driver.
Obviously, lithium batteries are going to lose charge in colder weather - that's just physics, but the problem here was twofold: one, the inherent limitation in the battery itself, but perhaps more importantly, how the car reports available charge to the driver in those conditions. If the car tells me that I have 100 miles to drive, I should have 100 miles left to drive. That it does not is a design flaw, and one that should not have been overlooked, plain and simple.
This article is _exactly_ why we're not getting one for the fleet anytime soon, and it's basically the answer I've been giving people since the Roadster came out (and the questions started).
Tesla is an awesome, awesome company. I'm a fan. I'm thinking of getting a Model S for myself. I think (and hope) they're going to be huge.
But they're not ready for the truly mass-market quite yet - and car rental customer (even luxury car rental customers) are the mass market.
I could see the exact scenario outlined in the article happening to renters constantly - except for one difference: We would be yelled at by the customers, not Tesla ;) ("Why is my car saying 'battery dead'? I did nothing wrong. Send a truck to pick me up or I'm writing a bad review about you guys.") Sigh.
Anyway, I'm still a fan despite the headaches - and I know they'll grow out of it.