That Tesla Data: What It Says and What It Doesn’t
wheels.blogs.nytimes.com
That Tesla Data: What It Says and What It Doesn’t
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Re: That Tesla Data: What It Says and What It Doesn’t
#2From the article, "Beginning early in the morning of my second day with the car, after the projected range had dropped precipitously while parked overnight, I spoke numerous times with Christina Ra, Tesla’s spokeswoman at the time, and Ted Merendino, a Tesla product planner at the company’s headquarters in California."
That quoted sentence includes the interesting phrase "Tesla's spokeswoman at the time," seemingly implying that the company has a new spokesperson in just the last few days. Who speaks for the company to the press now? It appears that Christina Ra used to work for Honda
http://automobiles.honda.com/2012/cr-z/blog.aspx?Author=5
and LinkedIn suggests she works for both Tesla and SpaceX
https://www.linkedin.com/in/christinara
with the title "senior manager, communications" for Tesla.
"I spoke at some length with Mr. Straubel and Ms. Ra six days after the trip, and asked for the data they had collected from my drive, to compare against my notes and recollections. Mr. Straubel said they were able to monitor “certain things” remotely and that the company could store and retrieve 'typical diagnostic information on the powertrain.'
"Mr. Straubel said Tesla did not store data on exact locations where their cars were driven because of privacy concerns, although Tesla seemed to know that I had driven six-tenths of a mile 'in a tiny 100-space parking lot.'"
So just what is the spatial resolution of the data stored by Tesla? Who can speak for the company on that exact issue, for the record?
I'm amazed, by the way, that commenters here and elsewhere claim that something is easy to see because it can be seen in a Google aerial photo in broad daylight in the summer, when the actual visibility issue is seeing the same thing from a car, while driving, at night in winter. I know lots of drivers who can drive right past things without seeing them, even while looking for those things, if they are driving in an unfamiliar location at night.
AFTER EDIT: Thanks for the several interesting comments in reply to this comment. I'll use my edit window to dump in some links from earlier threads on HN. There was an extensive, and on the whole rather favorable, review of the Model S from The Verge
http://www.theverge.com/2013/2/12/3969260/going-the-distance...
submitted to HN while most participants were discussing the John Broder New York Times review. (Most participants missed the discussion on the article from The Verge, which is too bad, as the article has interesting photographs of the car and a lot of thoughtful commentary about its trade-offs as a vehicle for regular use.)
http://news.ycombinator.com/item?id=5208154
The author of the report in The Verge takes care to mention, "Tesla hopes for its first quarter of black ink this year after a decade of operation, but make no mistake, it’s still in the throes of startupdom. Much of its working capital has come from nearly half a billion dollars in low-interest rate government loans. It has just a few dozen dealers around the world."
ONE MORE EDIT: Reasonable taxpayer and consumer minds can differ, and the differing opinions are widely expressed here on HN, but on the issue of the data-logging, I trust Tesla LESS after the back-and-forth about how Tesla thinks the reporter drove than I did before I saw Tesla's response. Tesla has HUGE taxpayer subsidies keeping its business afloat. Its response to questions about its technology's actual usefulness seems to be to go into attack mode whenever a reporter raises questions about the Tesla driving experience after driving a Tesla car. That doesn't make me think I want to drive a Tesla car. If the cars are really great for driving in places that have snow in winter, word of mouth should be able to tell that story, without any corporate P.R. spin. I note that there are many other news stories out right now, some of which have already been submitted to HN or mentioned in comments, in which onlookers express their opinion that Elon Musk has come out of this looking defensive. The product seems to be lacking in basic features I would need where I live, namely reliable estimates of remaining driving distance in winter, and that seems to speak for itself.
Re: That Tesla Data: What It Says and What It Doesn’t
#3Two bits are completely non-sensical to me, is there any battery technician or otherwise knowledgeable person that can indicate in what conditions this makes any sense?
> Beginning early in the morning of my second day with the car, after the projected range had dropped precipitously while parked overnight, I spoke numerous times with Christina Ra, Tesla’s spokeswoman at the time, and Ted Merendino, a Tesla product planner at the company’s headquarters in California. They told me that the loss of battery power when parked overnight could be restored by properly “conditioning” the battery, a half-hour process, which I undertook by sitting in the car with the heat on low, as they instructed. That proved ineffective; the conditioning process actually reduced the range by 24 percent (to 19 miles, from 25 miles).
If there is one thing that will use up large amounts of energy it is electric heating, I find it hard to believe that using a heater as a consumer would regenerate the battery capacity in excess of what the the heater is consuming unless most or all of the energy was directed at the batteries. The exterior of a car will drain heat energy about as fast as you can put it in under cold conditions (or faster...).
> It was also Tesla that told me that an hour of charging (at a lower power level) at a public utility in Norwich, Conn., would give me adequate range to reach the Supercharging station 61 miles away, even though the car’s range estimator read 32 miles – because, again, I was told that moderate-speed driving would “restore” the battery power lost overnight. That also proved overoptimistic, as I ran out of power about 14 miles shy of the Milford Supercharger and about five miles from the public charging station in East Haven that I was trying to reach.
That does not make any sense either. Any kind of consumption will ultimately reduce the available range, you don't restore by removing joules from a pack.
I've lived in a house powered with batteries, solar and wind for a long enough time to know that indeed temperature affects battery capacity, sometimes dramatically. But consuming power under cold conditions never put energy back in. Is this different for the kind of batteries that the Tesla uses?
Or is the 'Tesla said' claim just an effort to get out from under the apparently non-sensical decisions that were made here?
Or are Tesla spokespeople and product gurus totally clueless (which would seem to be very hard on the imagination)?
All the hard data from the Tesla logs except for the 'shutdown' is contradicted by words apparently spoken (and probably unverifiable except for 'he said/she said' style debate) rather than actually refuting the data.
Re: That Tesla Data: What It Says and What It Doesn’t
#4Can't wait to hear reResponse from Elon/Tesla.
Re: That Tesla Data: What It Says and What It Doesn’t
#5> I was given battery-conservation advice at that time (turn off the cruise control; alternately slow down and speed up to take advantage of regenerative braking) that was later contradicted by other Tesla personnel.
What the heck? Does this guy seriously think that braking and then speeding up will conserve battery? Maybe the adage "don't attribute to malice what can be explained by stupidity" is true.
Re: That Tesla Data: What It Says and What It Doesn’t
#6Two bits are completely non-sensical to me, is there any battery technician or otherwise knowledgeable person that can indicate in what conditions this makes any sense? > Beginning early in the morning of my second day with the car, after the projected range had dropped precipitously while parked overnight, I spoke numerous times with Christina Ra, Tesla’s spokeswoman at the time, and Ted Merendino, a Tesla product p…
> All the hard data from the Tesla logs except for the 'shutdown' is contradicted by words apparently spoken (and probably unverifiable except for 'he said/she said' style debate) rather than actually refuting the data.
If they did it through regular customer service, would it have been recorded? I suspect not or else the evidence would have been trotted out already.
Re: That Tesla Data: What It Says and What It Doesn’t
#7Overall I think Broder acquits himself well, and his explanation about circling the Milford parking lot makes sense. Also, the Tesla engineer he was on the phone with at the time should have been able to tell Musk that happened (or Tesla should have just asked Broder to comment before posting the rebuttal).
His action here is still hard to understand:
> The Tesla personnel whom I consulted over the phone – Ms. Ra and Mr. Merendino –told me to leave it connected for an hour, and after that the lost range would be restored. I did not ignore their advice.
So it sounds like he didn't speak to Tesla personnel after he charged at the weak station in Norwich for an hour. If I were him, I'd call them back and say, "Uh guys, it says it only has 32 miles left and I have 61 to go. Maybe I should give it another hour?"
Re: That Tesla Data: What It Says and What It Doesn’t
#8I need more popcorn. This is great!
Re: That Tesla Data: What It Says and What It Doesn’t
#9Two bits are completely non-sensical to me, is there any battery technician or otherwise knowledgeable person that can indicate in what conditions this makes any sense? > Beginning early in the morning of my second day with the car, after the projected range had dropped precipitously while parked overnight, I spoke numerous times with Christina Ra, Tesla’s spokeswoman at the time, and Ted Merendino, a Tesla product p…
Looking at the plots from Musk's blog post, the battery state of charge diminishes a bit overnight, but the estimated range diminishes much more. Presumably because a cold battery has a shorter range. As the battery warms up, the estimated range should go up as well.
How much the range goes up probably depends on how much the battery warms up; in the cold morning weather in Norwich, the battery may have warmed up less than the Tesla people were expecting.
Re: That Tesla Data: What It Says and What It Doesn’t
#10I'm over this he said she said with NYT vs Elon Musk. I love the concept of the Tesla, let's just put up or shut up. Who cares about the times, let's get a new, in depth, independent study. But let's get past this soap opera.