The speeding, the driving around in circles, the putting the heat up, the detour even the not charging it overnight - no one cares, because that's pretty normal driving behaviour for your average person (even though the reporter wasn't truthful about those aspects).

No, the problem was he unplugged the vehicle when it said 32mi of charge left to go on a 62mi trip, driving for over 20mi on 'empty', past other recharge stations. That's a sign he wanted the car to fail, quite deliberately.

Jeremy Clarkson is an assbag.

Atreyou40: " I'm no physicist, "

That's an understatement.
Yes, I know what regenerative braking is.  You, unfortunately, do not.  You may think you do, but you don't.
The energy reclaimed from a stop is never, ever greater than the energy taken to move the car to get to that point.  It can not be, no matter what tech is invented, because of the second law of thermodynamics. (And before you farkers start: yes, if you were rolling down a hill *a given stop* might regenerate more energy, you pedant bastards. But it took you more energy than the 'extra' reclaimed energy to get up the damn hill in the first place. So unless you're on a one-way trip from Boulder to the damn sea, elevation is a wash, at best.)

So, yes, electric cars do better than ICE cars in traffic, because they don't waste energy when stopped.
And, yes, cars with regenerative braking do better in traffic than cars without, because they recoup some of the energy that would have been lost.

But that doesn't mean that an electric car with regenerative brakes in traffic is more efficient than an electric car with regenerative brakes, driven at 45-52 mph on the highway, as the author claimed he was doing.

And taking a 60 highway mile trip, and turning it into 60 highway miles + 2 city miles, is never, ever going to result in less energy needed for the whole trip. Even if the 2 city miles magically took 0 energy, it would simply be a wash.  And zero energy is, again, impossible unless your trip involves slowly rolling into the sea.  And we could only *be* so lucky, were that the case.

I can say from a great deal of personal experience that the NY Times is full of shiat and has absolutely no interest in publishing the truth.

orbister: "Even with stop-and-go, I'd expect two miles in city traffic to use less energy than two miles at motorway speeds."

You might be surprised by reality then.  There's an advantage to slow speed, but stop-and-go kinda ruins it and the highway penalty only kicks in when you're traveling at speeds the author claimed he only 'very briefly' achieved.

Further, even if you expected that 2 miles in the city would be better than 2 miles on the highway, surely you'd recognize that trip_distance + 2 miles is going to require more energy than trip_distance, regardless of how efficient the vehicle is during those extra 2 miles.

RexTalionis: Also, I think the most damning thing about this test drive comes from Musk's blog:

"When he first reached our Milford, Connecticut Supercharger, having driven the car hard and after taking an unplanned detour through downtown Manhattan to give his brother a ride, the display said "0 miles remaining." Instead of plugging in the car, he drove in circles for over half a mile in a tiny, 100-space parking lot. When the Model S valiantly refused to die, he eventually plugged it in."

Jalopnik actually had some coverage on this - depending on the path taken, that gas station was big enough that driving around it once looking for the electric charger could be about half a mile.  http://jalopnik.com/tesla-claims-model-s-driving-logs-show-nyt-report e r-wor-192254006

To me, the whole thing seems pointless.  I mean seriously, it's an electric car that can go 300 miles on a charge, which is what a normal car does on about one tank of gas.  How many trips do you take that require more than one tank of gas?  Either you want one or you don't, but trying to split hairs about cross country performance or some crap is just silly.

Tesla has released their logs:

http://www.teslamotors.com/blog/most-peculiar-test-drive

Desquamation: Tesla has released their logs:

http://www.teslamotors.com/blog/most-peculiar-test-drive

That's why this Broder idiot needs to stop fighting his false reporting.  He needs to own up to his lies, or slink away quietly.  He can't win.  Tesla has farking computer data that tells them exactly what the car was doing for the whole test drive.

Magorn: " his is more realistic test  "

Yeah, people take road trips all the time where they don't top off their fuel tank.
I know the last time I took a road trip and coasted into the first gas station on fumes, I made sure I only got three-quarters of a tank before I started the next, longer, leg of my drive.
And when the car says I only have enough fuel to make it half-way to my destination, I go ahead and stop fueling and try to make it anyway.
And when the car is repeatedly warning me we're out of fuel, I routinely roll past fueling stations.

Because, ya know, that's just how "real people" drive.
Maybe engineers do better, but we can't all have fancy educations.

I skimmed through this thread but it appears no one has pointed out that this is Broder's response from two days ago, before the data was released.

Just so we're clear, this is the same newspaper that had an Editor-in-Chief ask their readers if they should do investigative reporting or not.

At first I thought they were trying to get into the "opinion" business.  Turns out, they just don't know how investigative journalism works.

Atreyou40: If there's no efficiency to be gained then why bother trying to recapture the kinetic energy of the car?

You're obviously incredibly unintelligent, the the point where attempting explanation is a waste of time and energy. But here is to hoping someone else reading is less stupid than you are.

The trip begins and ends with the car at a complete stop. Ergo the net effect of energy gain from stopping the car between driving styles is zero. An object in motion tends to remain in motion, while an object at rest tends to remain at rest. Ergo the energy necessary to maintain speed is always less than the energy to initiate motion. Ergo it is always more energy efficient to travel at a consistent speed than to start and stop repeatedly.

There may be design flaws in things like transmissions, gear and axles, aerodynamics, etc with the car. For example, Nisan and Toyota love those boxy retarded cars which suffer greatly aerodynamically. A properly designed car will always have better highway rating than city rating. That is why the Tesla Model S, Chevy Volt and Ford Taurus do better on highways, while trash cars like the Nisan Leaf do not.

fluffy2097: Only most east coast highway service stations with actual services. Here's proof it could easily have been 0.4 miles to find a charger.

Your account is way too old to be a shill or a paid troll, so I am sort of wondering why you are so diligently siding with the reporter on this one.  Yes, I agree Musk is coming across pretty douchy, but in this case the facts really do seem to show that the reporter was even more of a douchbag.

If the data logs are un-modified, then the reporter is clearly in the wrong.  This is a big IF, and I have a feeling that if the NYT doubles down on this derp, then we are going to see how admissible they are in court, and how solid an evidence trail they can construct.  However, it would be very difficult to fake this data.  They could manipulate speed graphs, but there are too many interconnected factors that would no longer add up.  If they just stretched the scale to show him driving faster, the area under the curve is going to grow into a distance substantially longer than the trip he took.  As someone who used to work in an engineering lab, I don't think that Tesla had long enough to construct a false data-set that would hold up to any sort of scrutiny.  Remember it is not just the speed, distance, and charge data they would have to fake, but also the voltage loads on various components, mechanical data, and other internal information.  The only problem Tesla has is that most Americans are too dumb to interpret graphs.

So guess you are either a troll (paid?) looking for reactions, or you have some sort of personal attachment to the NYT or the 'reporter.'

fluffy2097: MrSteve007: Yep, that's what he said - but not what he did.

You need new glasses. The logs and he both say he had 185 miles at Norwich

MadCat: No, they both say he had 185 miles at Milford Supercharge #1. He had 35 miles when he left Norwich.

/Perhaps you should lay off the insults a bit?

When I said he only needed to go 45 miles, I'm referring to this part in his article:

"I drove, slowly, to Stonington, Conn., for dinner and spent the night in Groton, a total distance of 79 miles. When I parked the car, its computer said I had 90 miles of range, twice the 46 miles back to Milford. It was a different story at 8:30 the next morning."

The reporter only had to drive 46 miles to get to the Millford supercharger when he woke up, which could have topped off his battery in less than an hour and given him some 280 miles of range. We can see that he had about 35% of the battery life when he got into the car at 400 miles into his trip. With a car equipped with an 85 kWh battery, leaving 5 kWh as reserve, he would have had 24 kWh of usable power in the car (the same capacity as a Nissan Leaf, which will travel 65 miles in those cold conditions). Instead, he sat in the car, running the heat for at least 30 minutes, and then drove to a much slower level II station - where he only briefly charged.

fluffy2097: MadCat: No, they both say he had 185 miles at Milford Supercharge #1. He had 35 miles when he left Norwich.

/Perhaps you should lay off the insults a bit?

So you think its fine that he went from 90 miles to 25 overnight and was FORCED to stop at Norwich to limp to the superchargers that he was supposed to be testing? That's not a problem with the car at all could it be?

Then he should have just wrote that and been done with it. as it is, it's pretty deliberately driving the car to fail to leave without enough power to make your next stop. He could have charged it for a bit longer there, or a bit longer at the previous super-charger, or stopped off at another charger further along... But he didn't. He drove it until it died, to get a picture of it getting towed. His article was definitely lying in places, but if he stuck to the truth, and just griped at having to wait half an hour because the weather sapped his charge, he would have been fine.

fluffy2097: Theaetetus: For instantaneous position, you're correct. However, you can assume that the car is not teleporting from a standstill every 3 meters, so, after averaging multiple position readings over time, the GPS-based average speed should be very, very accurate.

No, they should be precise.

Accurate is entirely different.

/you're still 3 meters off when you're off consistently by 3 meters.

If I'm "consistently off by 3 meters" in my distance measurement, then my speed is  perfectly accurate. Remember, dx/dt of a constant is 0.

Atreyou40: They even call it magic.  So yeah, you two are idiots.

Entropy, how does it work?

orbister: RexTalionis: I'm confused. He thinks stop and go will actually use less power than simply cruising at speed? Even with battery regeneration from braking, did he think that he's not expending more power having to accelerate a car from zero to whatever than he will get back through regeneration?

Slow speed driving uses less energy than high speed driving. Even with stop-and-go, I'd expect two miles in city traffic to use less energy than two miles at motorway speeds.

Goddamn you're stupid.

gweilo8888: MadCat: The logs that Tesla released directly contradict statements made by the reporter. Cue NYT Reporter accusing Tesla of falsifying data...

Does it? Because frankly, I see periods of speeds not terribly dissimilar to what the journo claimed. In fact, similar and consistent enough that if anything, I'd guess the speedo is off on the car, and the journo was exceeding the speed he believed himself to be driving due to a hopelessly inaccurate speedo. (In other words, a speedo like pretty much every car I've ever driven -- few have ever come within 5mph of accurate while driving at 55mph for me, showing readings anywhere from sub-50 to over-60.

So you are saying the logs and the speed indicated on the speedometer are from different sources of data?  If the car's computer was capable of knowing and logging the actual speed why wouldn't that same data stream go to the speedometer as well?

While your point of speedometers often not indicating actual speed is probably correct, your conclusion is incongruous with the facts as we know them.

noitsnot: I kind of figured that was just circling to get a spot - as most folks that live in big cities have to do.  The spots are always all full, and you gotta circle (with a bunch of other vultures) to get a spot when one opens.

Then why wouldn't the article author admit to doing that instead of blatantly lying and saying he wasn't even in a parking lot?

RexTalionis: Also, I think the most damning thing about this test drive comes from Musk's blog:

"When he first reached our Milford, Connecticut Supercharger, having driven the car hard and after taking an unplanned detour through downtown Manhattan to give his brother a ride, the display said "0 miles remaining." Instead of plugging in the car, he drove in circles for over half a mile in a tiny, 100-space parking lot. When the Model S valiantly refused to die, he eventually plugged it in."

No, the most damning part is that he got to the last recharge station and only charged it enough to get halfway to his final destination.  On what planet do you say, "I need to go 60 miles, 30 miles worth of fuel ought to get me there"?

The circles in the parking lot could have been him looking for a spot, the temperature and speedometer readings were off, but not by that much.  Not adding enough fuel to make it where you're going and then blaming the car is idiotic.

RexTalionis: I'm confused. He thinks stop and go will actually use less power than simply cruising at speed? Even with battery regeneration from braking, did he think that he's not expending more power having to accelerate a car from zero to whatever than he will get back through regeneration?

Came for this essentially.

"She said to shut off the cruise control to take advantage of battery regeneration from occasional braking and slowing down. Based on that advice, I was under the impression that stop-and-go driving at low speeds in the city would help, not hurt, my mileage. "

Which confirms that people go into things like Journalism, theater, etc because they are utterly stupid and cannot survive in any other "profession" in the world.

The NYT used to be a great newspaper, but lately it seems that every section has its own political agenda. Pathetic. I should say that every new tech has issues that get worked out. I seem to recall the NYT laying into the Honda FCX Clarity due to using Hydrogen fuel cells, and it being difficult to fill on the east coast, thereby making the handling and ride bad.

They also called the Alero a good used car buy a few years back. I own an Alero, and I'm sure it was invented and built by Satan.

At this point, if the NYT likes a car, I avoid it. And vice versa.

RexTalionis: I'm confused. He thinks stop and go will actually use less power than simply cruising at speed? Even with battery regeneration from braking, did he think that he's not expending more power having to accelerate a car from zero to whatever than he will get back through regeneration?

Journalists are not renowned for their knowledge of fields other than journalism.

Unless the Tesla logs are falsified, this reporter will be posting his resume in a New York Minute.

Based on contradiction of direct statements in his article I'm going to say he started with a premise; The EV would under-perform and made sure that conditions of the test ensured it failed. No different than some bozo who decides to drive an additional 50 miles after the gas warning light has come on in a standard vehicle.

Follow the money trail.  Which big oil company is adding to the reviewer's income?

gweilo8888: " if that's the advice Tesla reps are giving to customers  "

But does that sound remotely plausible?  A maker of electric cars saying "Adding stop-and-go traffic to your trip will *improve* your total range"?
The only person claiming they got that advice is the author whose story was just gutted by the actual trip data.
Are we really supposed to take him at his word on this?

RexTalionis: "I think the most damning thing about this test drive comes from Musk's blog: "

The blog post is full of "wtf" data.
http://www.teslamotors.com/blog/most-peculiar-test-drive

Musk clearly sounds like he has the right of it: this guy had an preconceived conclusion and set out to create some evidence to justify it.

He obviously left the dome light on overnight.

Ask yourself, who has the greater motive to lie:

1. A gabillionaire struggling to create credibility for a corporation that took half a billion in federal alt-energy money, and sells a beautiful electric car for twice what most Americans make in a year.

2. Or a long-time reporter for the best newspaper in the world, a guy who has never had his credibility seriously questioned, who has written on the environment for decades.

Ask yourself whether it's possible that the data is somehow screwed up -- heaven knows I could produce a chart right now proving that you are actually a cat.

Seriously. Elon Musk isn't gonna give you a ride in his rocket because you White Knight him on Fark or Reddit.

MadCat: Bullseyed: MadCat: The issue here I think

The issue here is you're arguing against people on both sides...

I'm sorry, I didn't know I had to take sides. You want to provide some evidence to show me where I'm wrong, or are you just looking for a fight?

In this thread you have argued:

1.) That regenerative brakes are a magical perpetual motion device
2.) That regenerative brakes can never add distance city vs highway because of the law of conservation of energy

There is always "sides" when it comes to physics, because one side is factual and the other side is either idiots or trolls.

MrSteve007: But if you look at every other EV on there (RAV4 EV, LEAF, BMW ActiveE, Fiat 500e, Mitsubishi i, Honda Fit EV, and Scion iQ EV, they all get quite a bit better city MPGe than highway.)

Luckily we're on an article about the Model S, so that doesn't mean shiat, moron.

MadCat: The issue here I think

The issue here is you're arguing against people on both sides...

fluffy2097: MrSteve007: fluffy2097: He had enough range to make it to the next one when he left the first.

I wonder what the range meter said 5 minutes after he left the supercharging station and decided to go blasting down the freeway at 83mph with the heater on full blast.

Straw man, He pulled in for the night with enough range to reach the next station, and left in the morning without enough charge to get there.

1.) You demonstrate here that you don't even know what a strawman is, by using the term incorrectly.
2.) You're talking about an entirely different leg of the trip. Due to your repeated misuse, it must be assumed that either you're illiterate or intentionally repeatedly referencing the wrong leg of the trip because you are utterly wrong.

fluffy2097: (Remember, civilian GPS is only accurate to a few meters we don't get milspec 2" accurate GPS)

That is factually incorrect. Civilian GPS has been exactly as accurate as military GPS for more than a decade, and modern GPS satellites do not even have the capability to selectively degrade the service.

fluffy2097: Because he was testing the supercharging system, not the Tesla S.

If he was testing the supercharging system, he would have plugged in the car, observed that it did in fact charge, and been done with his test.

Atreyou40: " I never said it was going to "be greater". "

If you understand that you're losing energy, then you understand that every stop and go is a net loss.
Every single time, you lose energy. And the more it happens, the more energy you're losing. Even if you're not going very far.
So there can be a dramatic difference in energy consumption over 2 miles, based solely on how much stopping and going you do, even though you have super-neat regenerative brakes.

So if you happen to be driving through a section of road that's notorious for the absurd nature of its stop and go traffic -- and in winter, where climate control is eating your battery as a function of time, not distance -- then surely you realize that a detour of "only" 2 miles, may well be a significant drain on the battery,* even though* your regenerative brakes are making you much more efficient than if you'd been in an ICE car without them.

And *that* is "The Point".  Regenerative brakes are good, but not so good that they can remotely outweigh the energy losses of driving "only" 2 miles of *Manhattan*, in winter.

fluffy2097: MadCat: No, they both say he had 185 miles at Milford Supercharge #1. He had 35 miles when he left Norwich.

/Perhaps you should lay off the insults a bit?

So you think its fine that he went from 90 miles to 25 overnight and was FORCED to stop at Norwich to limp to the superchargers that he was supposed to be testing? That's not a problem with the car at all could it be?

It is only a problem if you have zero understanding of science. You phone battery will run down overnight if you don't plug it in either. Imagine that!

fluffy2097: /since you can't read the article

You quoted the wrong portion of the trip. You must have gone to public school.

Theaetetus: MadCat: fluffy2097: MrSteve007: fluffy2097: He had enough range to make it to the next one when he left the first.

I wonder what the range meter said 5 minutes after he left the supercharging station and decided to go blasting down the freeway at 83mph with the heater on full blast.

Straw man, He pulled in for the night with enough range to reach the next station, and left in the morning without enough charge to get there.

And the part you refuse to accept: He pulled into a charging station that morning, granted not a supercharger, but a charging station non-the-less, and LEFT again even when the car TOLD him he didn't have enough power to make it to the supercharger.

This reporter decided that batteries losing charge overnight wasn't enough of a story. He had to create a situation where the car had to be rescued. That is what we're annoyed about,

Yep. Knowing he had to go 61 miles, he charged it up for 32.

Interestingly, on the way to Milford, he drove past another charger that was less than 32 miles from Norwich.

Atreyou40: You're both dumbasses. It's called "regenerative braking" an it's been around since the first hybrids and the idea is that a car in motion has some measurable inertia and to use the brakes as a capture device for that energy. I'm no physicist, and I have my doubts about the efficiency of such a thing given our current technology, but I have no doubt it's possible and even beneficial and can extend the range of an electric car by a couple miles, if not more. Here, why don't you go learn something:

http://en.wikipedia.org/wiki/Regenerative_brake
http://auto.howstuffworks.com/auto-parts/brakes/brake-types/regenera ti ve-braking.htm
http://green.autoblog.com/2009/04/16/greenlings-what-is-regenerative -b raking-and-what-types-are-ther/

There's even a youtube video for the spectacularly ignorant:

http://www.youtube.com/watch?v=y8jRAwIzPTM

Oh what the hell, here's more links:

http://www.wisegeek.org/what-is-regenerative-braking.htm
http://www.fueleconomy.gov/feg/hybridanimation/fullhybrid/fullhybri ...

No, you're the spectacularly ignorant dumbass. Why? Because regenerative braking only recoups SOME of the energy lost to braking. In other words, if you slow down and then speed back up again, you lose energy versus staying at a steady speed.

If that wasn't the case, you'd have invented a perpetual energy machine.

So take your know-it-all attitude and shove it up your jacksie, you farking arrogant tool.

MrSteve007: In stop and go, or streetlight to streetlight traffic, a vast majority of the energy to move an electric car is road friction and the energy required to accelerate.

Actually if you look at  http://en.wikipedia.org/wiki/Electric_car  you will see that the Tesla Model S, the Chevy Volt, and the Ford Taurus all get better highway than city fuel economy.

Atreyou40: You're both dumbasses. It's called "regenerative braking" an it's been around since the first hybrids and the idea is that a car in motion has some measurable inertia and to use the brakes as a capture device for that energy. I'm no physicist, and I have my doubts about the efficiency of such a thing given our current technology, but I have no doubt it's possible and even beneficial and can extend the range of an electric car by a couple miles, if not more.

What you're saying is you lack even a basic understanding of physics.

The only way regenerative braking could "add" energy to the car's closed energy system is if you braked while going downhill, and if your trip began at "uphill" from the downhill location. Using the engine (at less than 100% efficiency) to accelerate, then using the brakes (at less than 100% efficiency) cannot add charge to the system. Additionally, if you use energy to travel uphill, you cannot then gain energy by going downhill, unless the amount downhill is greater than the height uphill.

Magorn: Your car can go for about 20-30 mils after the gauge reaches E for a reason

Maybe it can, maybe it can't. I'd rather not test it myself.  But if you depend on that and run out of gas it's your fault and not the car.

DaAlien: Because gas powered cars don't recover energy by regenerative braking?

What do gas powered cars have to do with EPA-MPG-comparable ratings on hybrid and electric vehicles?

cmunic8r99: fluffy2097: What asshole drives around in a parking lot with an area of 3.5 miles for 5 whole minutes and goes 0.6 whole miles to find a spot?

How many parking lots with 100 spaces have an area of 3.5 miles?



Only most east coast highway service stations with actual services. Here's proof it could easily have been 0.4 miles to find a charger.

fluffy2097: MadCat: Oh I fully agree it's a problem. The reporter should have reported on THAT problem. Instead he failed to take steps to replace the lost range and failed to disclose or acknowledge that he caused the car to run out of power. The article should have been about how he had to spend extra time at Norwich to replace overnight power loss, not about how he had to be towed back to a charge station.

The article was about the super charging system along the east coast and how it was supposed to allow a Tesla S to go on road trip just like you would with a gas powered car.

The supercharging stations did not do this. They caused him to run out of power because they were not close enough together (Something Elon Himself believes) and because the batteries are clearly severely discharged by cold weather.

/Teslas seem to run into a lot of "software glitches" that "cause lost battery capacity"

No, the super-chargers didn't cause him to run out of power, he caused himself to run out of power, quite deliberately. Complain about the technology if you like, and it is a new technology so it's far from perfect, but the reporter still lied.

What asshole drives around in a parking lot with an area of 3.5 miles for 5 whole minutes and goes 0.6 whole miles to find a spot?

/oh, anyone who's ever been in a full parking lot.
//Seriously Elon? You want me to believe this sort of shiat is abuse?

fluffy2097: Before I set out from my home in suburban Washington, I informed Tesla that I intended to make a brief stop in New York and that I would spend the night in the vicinity of Milford rather than trying to make it to Boston, which was theoretically possible with a full charge at Milford, although it was a bitterly cold night - and that clearly affects the car's range. I added 185 miles of range at Milford, knowing that I wouldn't need 242 or 265 miles before recharging the next morning.When I parked the car for the night at a hotel, the range meter showed 90 miles remaining, and I was about 45 miles from the Milford Supercharger. As I recounted in the article, when I awoke the next morning the indicated range was 25 miles.

/since you can't read the article

Yep, that's what he said - but not what he did.


He recharged only to 72% at Millford. Almost immediately after giving it a 3/4's charge, he did an 80+ mph stint in the car, and kept about 65mph for the next 60 miles (even when you factor in a 5mph error in the speedo). He then parked overnight, without plugging in the car. When he woke up, he sat in the car and ran the heater for 30 minutes (which you can see the large decline in battery power @ 400 miles).

If you look at the range after the brief Norwich charge, he had some 28% of battery charge left, and according to the author, he only needed to go 45 miles. If you look at the point of the Norwich charge and when the car was effectively empty, it suspiciously looks like he traveled at least 50 miles.

It's pretty easy to see that if he had done any of these actions, the review would be far different:
-Had the reviewer charged the car for 10 more minutes at the Millford super charger (let alone fully charge it), he would have made it
-Had the reviewer trickle charged while he was sleeping at the hotel, he would have made it.
-Had the reviewer charged for 20 more minutes more at Norwich, he would have made it.
-Had the reviewer not done illegal speeds on the interstate and kept to the speed limit, he would have made it.

orbister: RexTalionis: I'm confused. He thinks stop and go will actually use less power than simply cruising at speed? Even with battery regeneration from braking, did he think that he's not expending more power having to accelerate a car from zero to whatever than he will get back through regeneration?

Slow speed driving uses less energy than high speed driving. Even with stop-and-go, I'd expect two miles in city traffic to use less energy than two miles at motorway speeds.

False. Acceleration uses energy. Maintaining a speed requires far less energy than constantly accelerating and decelerating.

fluffy2097: Theaetetus: one would expect a car on loan from the manufacturer would have the correct size wheels for its configuration data.

I expect it to be within 5mph +/-

Since I believe Tesla complies with Federal law, I expect it to be within 2.5% +/-. So, 5mph off, if you're doing 100 mph. Not if you're at 45.

The data discrepancy shows about 7-10 mph, but you've got that +/- 5mph on both tracking devices (Remember, civilian GPS is only accurate to a few meters we don't get milspec 2" accurate GPS).

For instantaneous position, you're correct. However, you can assume that the car is not teleporting from a standstill every 3 meters, so, after averaging multiple position readings over time, the GPS-based average speed should be very, very accurate.

I once ran out of gas, after I left my house with a gallon of gas in the tank, and tried to drive across the state.  How could this have happened to me?!

Why on earth is the NYT still letting him publish under their name?  This asshole is an obvious shill who lacks any kind of journalistic integrity.  Fire his ass, NYT.  There are literally tens of thousands of unemployed journalism majors who would happily do a much better job than he ever could.

fluffy2097: themanuf: So you are saying the logs and the speed indicated on the speedometer are from different sources of data? If the car's computer was capable of knowing and logging the actual speed why wouldn't that same data stream go to the speedometer as well?

Because data logging is can be done via GPS tracking whereas speedometer readings are based off rotations of the wheels, which is something that varies depending on the diameter of the wheels you have.

FTFY. We have no way of knowing whether the data logging was GPS data or speedometer data or both. Since it's a digital speedometer, the log could theoretically capture it.
Additionally, while you're correct about the speedometer readings being based of wheel rotation and size, one would expect a car on loan from the manufacturer would have the correct size wheels for its configuration data.

DaAlien: Tesla also claims the car was never fully discharged.

It may never have been fully discharged. The Roadster shuts down completely at 5 or 10% charge to avoid battery damage. Anyone know if the Model S shows charge or usable charge remaining?

RexTalionis: You know why your car's "city" mpg rating is almost always lower than your "highway" rating?

Because I don't have regenerative braking, and because I drive an internal combustion engine which, unlike an electric car, uses a non-negligible amount of energy even when stopped in traffic.

RexTalionis: orbister: RexTalionis: I'm confused. He thinks stop and go will actually use less power than simply cruising at speed? Even with battery regeneration from braking, did he think that he's not expending more power having to accelerate a car from zero to whatever than he will get back through regeneration?

Slow speed driving uses less energy than high speed driving. Even with stop-and-go, I'd expect two miles in city traffic to use less energy than two miles at motorway speeds.

You know why your car's "city" mpg rating is almost always lower than your "highway" rating?

If you're talking about a combustion engine car, yes. In a full electric, nope - city driving gives about 30% more range. In stop and go, or streetlight to streetlight traffic, a vast majority of the energy to move an electric car is road friction and the energy required to accelerate. As others have pointed out, electric cars also regain much of that energy when braking. In comparison, a combustion car has a lot of parasitic loss at lower speeds (cooling pumps, alternators, drive belts, etc), and far less combustion efficiency. As you get past ~30mph, wind resistance becomes stronger and stronger. That is what reduces range on electric cars.

Tesla's range vs. speed charts:


The EPA MPG of a 2013 Nissan Leaf

/if it's too small for you to read, 130 MPGe city/ 102 MPGe highway

I believe that Top Gear is going to test the Tesla in next week's show.  I'll definitely be watching now.

Popcorn Johnny: kalor: Hard raw data, un-manipulated, shows the reporter statement is false...that does prove who made the lying statement.

So tell me, how do you know it's un-manipulated?

Last I heard, Tesla was not gong to release the raw data.

Tesla also claims the car was never fully discharged. The flatbed driver disagrees:
http://jalopnik.com/towing-company-the-nyt-tesla-model-s-was-dead-wh en -it-196100064

In the periods he said he used cruise control, the data seems to show him using cruise control.  The "lie" seems to be that the data just show it being about 5mph higher than the article, which seems well within expected variation.

The key thing from the data for me is the graph that shows displayed remaining charge miles vs. actual miles traveled.  It looks like the displayed rating was consistently 30% over the actual achieved miles. Which seems like the basic claim the author was making.  The big overnight charge loss is supported in this graph as well; which I guess means that a trickle charge is pretty much required.

gweilo8888: MadCat: The logs that Tesla released directly contradict statements made by the reporter. Cue NYT Reporter accusing Tesla of falsifying data...

Does it? Because frankly, I see periods of speeds not terribly dissimilar to what the journo claimed. In fact, similar and consistent enough that if anything, I'd guess the speedo is off on the car, and the journo was exceeding the speed he believed himself to be driving due to a hopelessly inaccurate speedo. (In other words, a speedo like pretty much every car I've ever driven -- few have ever come within 5mph of accurate while driving at 55mph for me, showing readings anywhere from sub-50 to over-60.

That would relevant and interesting if car speedometers didn't tend read higher then your actual speed, to keep liability in speeding as a relative non-issue. If we apply the 'innacurate speedo' claim here we would have to assume that the speedo showed him 65 when he was actually traveling 60 and he claimed 54.

ringersol: Because, ya know, that's just how "real people" drive.

It is.

horrifically enough, that's exactly how lots of people drive.

Popcorn Johnny: MadCat: The logs that Tesla released directly contradict statements made by the reporter.

Is there any doubt that they would? Still doesn't prove who's lying here.

Hard raw data, un-manipulated, shows the reporter statement is false...that does prove who made the lying statement.  You seem to be implying because Tesla produced the logs they're obviously covering the whole thing up or making up data because it shows the Reporter fibbed on many accounts.

RexTalionis: I'm confused. He thinks stop and go will actually use less power than simply cruising at speed? Even with battery regeneration from braking, did he think that he's not expending more power having to accelerate a car from zero to whatever than he will get back through regeneration?

He was all like "fark Issac Newton" and shiat.

Most Americans won't change their driving habits or maximize the potential of the technology just because they have a car that runs on some other power source. He could have acknowledged that he was playing the part of the average crappy driver, not paying attention and not doing the necessary research -- because no one does that anyway -- or even admit that he was trying to sabotage the car to see what would happen. And this is how he outed himself as a terrible journalist, because his article didn't use the creative non-fiction techniques that would have made it the true hit piece he so desperately wanted it to be.

RexTalionis: I'm confused. He thinks stop and go will actually use less power than simply cruising at speed? Even with battery regeneration from braking, did he think that he's not expending more power having to accelerate a car from zero to whatever than he will get back through regeneration?

Slow speed driving uses less energy than high speed driving. Even with stop-and-go, I'd expect two miles in city traffic to use less energy than two miles at motorway speeds.

MadCat: The logs that Tesla released directly contradict statements made by the reporter. Cue NYT Reporter accusing Tesla of falsifying data...

Does it? Because frankly, I see periods of speeds not terribly dissimilar to what the journo claimed. In fact, similar and consistent enough that if anything, I'd guess the speedo is off on the car, and the journo was exceeding the speed he believed himself to be driving due to a hopelessly inaccurate speedo. (In other words, a speedo like pretty much every car I've ever driven -- few have ever come within 5mph of accurate while driving at 55mph for me, showing readings anywhere from sub-50 to over-60.

ChuckNorrisSays: Jeremy Clarkson is an assbag.

Possibly, but he did punch Piers Morgan in the face, so he does have that going for him.

RexTalionis: I'm confused. He thinks stop and go will actually use less power than simply cruising at speed? Even with battery regeneration from braking, did he think that he's not expending more power having to accelerate a car from zero to whatever than he will get back through regeneration?

In this house we respect the laws of thermodynamics!

''didn't do the necessary homework before testing out the car''

I'm shocked I tell you, shocked

/not really...

I support alternative fuel sources because I still want to hear the scream of a v12 or the burble of a supercharged v8 in 2070.