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Tesla S: The Perfect Car?

  1. May 17, 2013 #1

    russ_watters

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    Or, just almost perfect? 99 out of 100? I know this isn't a claim by Tesla, just a review, but (The review itself isn't available without a subscription.):
    http://www.cnn.com/2013/05/15/opinion/harley-tesla-best/index.html

    A synopses is here: http://money.cnn.com/2013/05/09/autos/tesla-model-s-consumer-reports/index.html

    1. Obvious: If it is only tied for highest score, why say it was the best and give it an almost perfect score? Sounds like something a used car salesman would say to you.
    2. Best/perfect versus what/with what criteria? This is the bigger issue:

    I don't doubt that the Model S is an awesome car, but to be just short of perfect, I can't see how it is being measured against anything but itself. Because different types of cars have different purposes, I would think it should probably be versus other cars in its type. Because clearly the Model S doesn't have the best - much less perfect - towing capacity, acceleration, range, cornering or kitchen.

    If you rank it against other sedans, it has some clear and serious flaws; the normal flaws that all electric cars have: range, charging time, charging station availability, cost (value), performance in adverse weather, etc.

    I suppose you could rank it soley against other electrics and call it the best, but near perfect? I think it has a little ways to go just in terms of usability due to the lack of charging stations and time it take to charge -- and I think that should matter.

    And these are just the obvious/inherent flaws of electrics. I have a hard time believing everything else about it is perfect -- but as said I haven't seen the review itself yet.

    Moreover, since it is a new car, there is no data on reliability/longevity/service cost, nor has it been crash tested (!). At best it should get an incomplete on that score.

    More from the USA Today opinion:
    What are they thinking? Is this a publicity ploy by Consumer Reports? They are supposed to be above those types of games.
     
  2. jcsd
  3. May 17, 2013 #2
    I've lost some respect for Consumer Reports after the antenagate 'scandal'. They are ranking the Tesla in comparison to other luxury sports cars. People that rich fly planes, rather then driving cross country, so the range issue is likely not a concern for them.

    Im surprised that they don't make gas generator trailers for electric cars. If you decide you are going to drive 300 miles somewhere, you'd just rent one and let it charge your battery while you drive. You wouldn't need it for ordinary city driving, so most people would use one once or twice a year at most. This would make the car more efficient then a hybrid because you wouldn't be carrying the weight of a gas engine and fuel unless you needed them.
     
    Last edited: May 18, 2013
  4. May 19, 2013 #3

    jim hardy

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    I'm waiting for cheap mass produced fuel cells to replace those awful pyrotechnic batteries.

    http://aluminum.org/AM/Template.cfm?Section=Home&template=/CM/HTMLDisplay.cfm&ContentID=15793

    That's almost as cool as Doc Brown's "Mr Fusion" on back of his Delorean.
    mrfusion-500x375.jpg
    pic courtesy of http://www.popcrunch.com/wp-content/uploads/2010/07/mrfusion-500x375.jpg
     
  5. May 20, 2013 #4

    mheslep

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    Based on the last time I signed up for CR reviews for cars, yes they rank against other vehicles in class. This time I think they throw the Tesla S in luxury sedans. The near perfect score means only that it scores very, very well on the list of items CR has traditionally chose to rank against - not everything imaginable. From the sample page available the standard set includes items like
    • Owner Satisfaction
    • Crash protection with side air bag
    • Fuel economy
    • Acceleration
    • Ride
    • Front seat comfort

    etc. I could easily see the vehicle out performing the competition in those areas, with some attention. Nothing in the luxury sedan class is going to beat an electric drive train for acceleration off the line.


    True, that's the case for all first year models CR rates, and IIRC they simply "N/A" the reliability category for all first year models. I'll speculate that the Model S reliability eventually comes in extremely high compared to its combustion engine based brethren with their vastly larger number of moving parts - belts, exhaust system, oil/air/fuel filters, fluid replacement, friction brakes, etc, etc.

    Yes it has - all road vehicles sold in the US require crash tests at independent labs, or so I gathered from my brief stent in testing some gear at one lab so certified. To my knowledge CR never does its own.
     
    Last edited: May 20, 2013
  6. May 20, 2013 #5

    jtbell

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    CR's numerical scores do not take reliablilty into account. They do that by applying a "Recommended" tag (with a checkmark in their ratings tables) to cars that both score high and have demonstrated good reliability. I think they wait until they have at least a year's worth of repair data, based on their annual surveys.

    I can't lay my hands on the issue that has the Tesla report, but I remember them saying for other cars in the past, in effect: "this car scores well, but we're not recommending it yet because it's too new and we don't have repair data."
     
    Last edited: May 21, 2013
  7. May 20, 2013 #6

    Redbelly98

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    I'll just make a general comment about calling it "near perfect". A 99 or 100 does not indicate something is (near) perfect, it indicates that the test was designed to rate substantially lesser cars.
     
  8. May 20, 2013 #7

    AlephZero

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    They had product recalls in both 2009 and 2010. (But hey, they only recalled a few hundred vehicles, cmpared with millions from other car makers, so they are obviously doing better than average :smile:)

    But I don't really see the purpose of a review in a mass-market consumer publication, except as "free" brand awareness advertising for Tesla.

    I would guess some of their 2,600 sales last year were to people who have no interest in using them to meet their transporation needs, any more than people buy $10,000 mechanical watches so they can know what time it is.

    But if GM and Nissan are trying to market electric cars as transportation devices, and Tesla are marketing them as status symbols, that might explain why Tesla outsold both GM and Nissan in the first quarter of 2013.
     
  9. May 21, 2013 #8

    mheslep

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    Not of the Model S. Those were the Roadsters, the first vehicle they ever made - in quantities of hundreds back then. Also, though recalls are important, they are more about systematic design defects, which is really not the same thing as reliability issues.

    CR reviews all kinds of luxury vehicles with relatively low sales, has for years. The Model S is currently outselling some of them.

    Perhaps, but now CR has provided rationale beyond that of status symbol. They rank many basic functions of any vehicle (e.g. the ride, front seat comfort, etc), and according to CR the Model S excels in them, at least more so than other vehicles in class (luxury sedan). A superior ranking in such classes might be easier to obtain in EVs, given the engineering opportunities opened up by elimination of the drive train forcing functions of combustion vehicles: tyranny of the long drive shaft, greater volume of the combustion engine (per unit power) plus all of its peripheral heat rejection items which eat into passenger space, vibration and noise (important in luxury vehicles), etc.

    So to address the OP: the CR review of Model S does nothing to eliminate the well know drawbacks of electric vehicles, but does provide more advantages to weigh against them in the case of the Model S.
     
    Last edited: May 21, 2013
  10. May 21, 2013 #9

    russ_watters

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    Setting aside a minor quibble about the definition of "perfect", I think I agree with you and that's my main complaint: That's "substantially lesser cars" as scored by their rating system, which does not take into account many attributes I think most people would consider important to making the determination. Ie, my "substantially lesser car" goes about twice as far without refueling and refuels in a fraction of the time. For my car, that's average, for the Model S, I think a lot of people would consider that a substantial shortcoming.

    Just to make sure I'm not misunderstood here, I want to make sure people are aware that I'm not saying the Model S is a bad car. In fact, if it is even 3/4 as good as they say it is, it is a truly astounding achievement. My criticism here is for Consumer Reports only.
     
  11. May 21, 2013 #10

    OmCheeto

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    Shall we criticize the people buying them too?

    pf.GO.TESLA.jpg

    Although my posts might indicate I'm an electric purist, I can assure you, that I am far from it.

    But the people who can afford these cars, I'm sure, can afford long range gassies*.

    ps. My criteria for a new car were that it ran, had 4 tires and a trailer hitch.

    ------------------------
    * Yes, I did just make up that word.....
    I was just trying to imagine what pejorative term people 50 years from now will call ICE powered vehicles. :tongue2:
     
  12. May 21, 2013 #11

    russ_watters

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    No, why would I? It isn't surprising that the initial sales are brisk. We'll have to wait and see what sales will be like after the novelty expires though.
    I like it.
     
  13. May 21, 2013 #12

    OmCheeto

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    Don't try and get on my good side.

    I'm older.
     
  14. May 21, 2013 #13

    Redbelly98

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    If you're single and a single-car owner, it's likely you need that one car to have the range for long trips.

    If you or your family have two or more cars, one of them can be highly efficient at the expense of a shorter range. Meanwhile you also have a standard gas-powered car for the longer drives.
     
  15. May 22, 2013 #14

    jim hardy

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    Tesla was brilliant to enter this into luxury car market.

    I drive $2000 cars because they last me half as long as $20,000 cars.
    An electric that's only good for local use and needs a $5,000 battery every few years doesn't make sense to me.
    But a lot of people will pay $70,000 for one as a status symbol or curio.
    If I had that kind of disposable income I'd buy electric utility stock .
     
  16. May 22, 2013 #15

    collinsmark

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    Or one could get an extended range electric such as the Chevy Volt or Cadillac ELR.
    http://www.chevrolet.com/volt-electric-car.html
    http://www.cadillac.com/future-cars/elr-electric-car.html

    But those who can afford a Tesla likely can likely also afford airplane tickets. Long range driving isn't the primary concern for a Tesla driver. That said, Tesla has set up a network of fast, DC charging stations that allow road trips from Los Angeles to San Francisco. A fast, DC charge gives about 150 miles per half hour of charging.
    http://www.teslamotors.com/supercharger
    [Edit: Oh, and charges are free, too.]

    City driving is where the advantages of electric cars really shine through. The instantaneous, high torque (equates to terrific acceleration at lower speeds) and ultra quiet are an incredible experience. You have to drive a modern electric to really appreciate it. I imagine that with the Tesla Model S, it's like a Rolls Royce packaged up like a sports car. That's probably what the Consumer Reports article was getting at.

    I know a couple of people who own Tesla Model S cars. And they do have some unmentioned disadvantages even for electrics. Based on some anecdotal observations, the Tesla Model S doesn't seem to be as electrically efficient (km per kWh) as my Volt. The Tesla has a bigger battery to haul, but my Volt has an internal combustion engine it's lugging around, so I don't think weight/mass is the only reason. Maybe it's the Tesla Model S's 317 to 443 lb·ft (430 - 600 N·m) of torque, and their driving styles. If I had that much torque I bet I'd drive pretty heavy-footed too. :smile:
     
    Last edited: May 22, 2013
  17. May 22, 2013 #16

    mheslep

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    That's the certainly part of the negative hype. Can you point to any data to firm up that assertion?
     
  18. May 22, 2013 #17

    dlgoff

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    "...Presented at a meeting of the American Chemical Society."

    http://portal.acs.org/portal/acs/corg/content?_nfpb=true&_pageLabel=PP_ARTICLEMAIN&node_id=222&content_id=CNBP_032579&use_sec=true&sec_url_var=region1&__uuid=da7ef387-505e-4a40-9803-1339fb490d47
     
  19. May 22, 2013 #18

    mheslep

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    Interestingly the EPA lists the Volt and Model S 60kWh as having the same electrical efficiency: 2.86 kWh per mile; the 80 kWh model is slightly lower.

    The reported specs from Tesla are 5.6 miles per kWh. Maybe that number assumes optimal temperature and driving style.

    The Model S battery chemistry has a little higher energy density. The Model S curb weight is 23% higher than the Volt, but then Model S is a larger vehicle: 11% longer, 10% wider.
     
  20. May 22, 2013 #19

    mheslep

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    Specifically:
    That's always been my understanding. So EVs with little or no battery thermal management, like the Nissan Leaf, may be expected to be on the low side of the above estimate. Tesla and the Volt both to temperature management of the battery. The Volt specifically limits the amount of charge depletion allowed in its relatively small 16 kWh battery.
     
  21. May 23, 2013 #20

    OmCheeto

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    Temperature management is one of the items they discuss at ChargeCar.

    From my data:

    Though I believe ChargeCar bases everything on Lead batteries, it would be interesting to see if this can be done with the Lithium batteries.

    From dlgoff's link:

     
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