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Transportation Upgrades

Tesla Roadster Update Extends Range 128

mrflash818 sends word that Tesla Motors has announced an upgrade for their Roadster vehicles that boosts the range from about 240 miles to almost 400. In addition to the battery improvements made since the Roadster launched in 2008, Tesla has a kit to retrofit the body to reduce its drag coefficient from 0.36 to 0.31. They also have new tires, which improve the rolling resistance coefficient by about 20%. They say, "Combining all of these improvements we can achieve a predicted 40-50% improvement on range between the original Roadster and Roadster 3.0. There is a set of speeds and driving conditions where we can confidently drive the Roadster 3.0 over 400 miles. We will be demonstrating this in the real world during a non-stop drive from San Francisco to Los Angeles in the early weeks of 2015." Tesla stopped producing the Roadster in 2012.
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Tesla Roadster Update Extends Range

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  • by crow ( 16139 ) on Friday December 26, 2014 @05:38PM (#48677241) Homepage Journal

    The one update they really should do along with the battery upgrade is add Supercharger support.

  • First post (Score:2, Funny)

    by Anonymous Coward

    But if we conserve energy, the environmentralists win!

  • Extended Range (Score:5, Insightful)

    by Firethorn ( 177587 ) on Friday December 26, 2014 @05:41PM (#48677257) Homepage Journal

    Summary: Lots of improvements in a number of areas can make a big, big difference.

    Since ~2008 I know they've increased the energy density of their 18650 cells by 20-30%, which would correspond to a 20-30% increase in range no matter what. After that it starts adding up quick.

    I wonder if they might end up restarting roadster production. For a small car manufacturer that could even be fairly logical - produce as many as you can for a relatively short period of time(few years), then shut down production for a few years to let the demand recover and grow.

    Perhaps more importantly, increasing the range of a car from 250 miles to ~400 also means that you could put a smaller battery pack in that costs nearly half as much, making it more affordable.

    It also helps show the longevity of Battery Electronic Vehicles. Though it's only been two years since they stopped producing it, they're still producing not just maintenance parts, but serious upgrades.

    • Re:Extended Range (Score:5, Informative)

      by crow ( 16139 ) on Friday December 26, 2014 @05:47PM (#48677281) Homepage Journal

      No, they can't legally sell them in the USA anymore without some serious engineering changes. They got a waiver on some of the safety regulations that has expired. They also had a limited contract with Lotus for the bodies.

      So to do a new run of roadsters, they would have to do a lot of engineering and essentially make a new car. Right now, they don't have the capacity in engineering or production to make more models; they're struggling to get the Model X out, and they've got their eyes on the III.

      I wouldn't be surprised if they make a new Roadster eventually, but I would put it at five years out at the earliest.

      Besides, given the performance of the P85D, I'm not sure how much more there would be besides a different body shape.

      • by Teancum ( 67324 )

        Lotus also retooled the production line that Tesla was using, which is another thing that killed the Roadster. Lotus didn't have a problem with Tesla continuing their relationship (well, sort of), but that would have also required some additional engineering effort to retool the customized components that Tesla was using.

        In short, like you said... it would require a whole new redesign from basically a clean sheet of paper that only superficially looks like the original Roadster. The battery technology wo

      • Have you sat in a Roadster?
        They're pretty uncomfortable. I'm only 5'10" and I felt claustrophobic in the driver's seat. Poor visibility and and hard to get into.

        Let the car die a respectable death.
        • Let the car die a respectable death.

          The roadster is very much a specialty car. It'll be hard to say how it'll look/perform if/when released in greater I agree with the others, if they 're-release it', it's going to be significantly changed, effectively a new model.

          One thing they'll likely do is use their now more or less 'standard' model S 'skateboard' battery & drivetrain system.

      • P85D.... drooooooool. I want. Now that there is an AWD version, these cars appear to be as desirable as a Mercedes Benz E63 AMG S 4matic. They cost about the same.

    • by AaronW ( 33736 )

      Tesla has indicated that they will do a new roadster but that won't be until after the Model 3 and it will be a new design from the ground up.

    • "Since ~2008 I know they've increased the energy density of their 18650 cells by 20-30%, which would correspond to a 20-30% increase in range no matter what."

      Don't they just use Panasonic cells? Last report I saw, they used NCR18650A 3100mAh cells, and I'm guessing by now they've moved on to the newer NCR18650B 3400mAh cells... which would explain the capacity increase. Where are you getting the info that they're manufacturing their own cells?

      • Simple enough: I don't because I never said they were manufacturing them. I say 'their' cells because while Panasonic is indeed making them, they're ordering so many that Panasonic is running custom 18650s for them - modified chemistry, reduced safety features* with a simple aluminum cap replacing them, etc... They're effectively Tesla's, because it's the only buyer(short of consumers getting them in the completed battery in their car) of those particular cells.

        Oh, and from my memory the Roadster was pow

  • by Fencepost ( 107992 ) on Friday December 26, 2014 @05:44PM (#48677267) Journal
    I'm pleased to see them backporting new tech to the older vehicles, and by doing this they also get replacement batteries into vehicles sold as much as 6 years ago (first introduced in 2008), though presumably they've had replacement battery packs available all along.

    I'm sure they're also going to be making at least some profit on these upgrade kits, and by not abandoning the older vehicles they probably do a lot to cement loyalty from those same customers who were willing & able to drop more than $100k when they first came out.
  • "There is a set of speeds and driving conditions where we can confidently drive the Roadster 3.0 over 400 miles"

    42 mph , downhill with a tail wind...

    • by TrekkieGod ( 627867 ) on Friday December 26, 2014 @06:02PM (#48677357) Homepage Journal

      "There is a set of speeds and driving conditions where we can confidently drive the Roadster 3.0 over 400 miles"

      42 mph , downhill with a tail wind...

      To be fair to Tesla, the driving conditions for their range estimates are actually usually very realistic. I have a 60 kWh Model S, and I match rated range while driving 65 mph in the summer with air conditioning on. It gets significantly worse in winter, and it gets much better in nice 65-70 degree weather days.

      • by Matheus ( 586080 )

        Also most all cars have that caveat on their range.

        My last three cars have been far from fuel economical (Turbo, Turbo, W8) but the difference between driving them like my grandma and driving them like myself is a good 50-100 miles on a tank.

        Even with myself the difference between City and Highway is significant. In my W8 I've gotten almost 370 on a purely highway trip but in the city I'm lucky to hit *260.

      • 'rated range'... What, did you sign an NDA?

      • by Cyfun ( 667564 )

        Worse in the winter cause you're blasting heat? Why not just put a coat on?

        • Worse in the winter cause you're blasting heat? Why not just put a coat on?

          People don't buy an $80k car so that they can wear a heavy coat instead of turning on the heater. People who can afford them just move closer to where they want to go in order to defeat range anxiety. #poorpeopleproblems

          • It's true but... There's a guy in Ottawa who's been blogging about his Nissan Leaf through 3 winters... One technique he uses to extend winter range is to pre-heat the interior of the car by plugging it in at home/work, even if only a 120vac outlet because the interior of the car will already be warm by the time he gets in to drive. Then he keeps the interior relatively cool while using the seat heater and steering wheel heater to keep himself comfortable.

            https://canadianleaf.wordpress.com/
            • It's true but... There's a guy in Ottawa who's been blogging about his Nissan Leaf through 3 winters... One technique he uses to extend winter range is to pre-heat the interior of the car by plugging it in at home/work, even if only a 120vac outlet because the interior of the car will already be warm by the time he gets in to drive. Then he keeps the interior relatively cool while using the seat heater and steering wheel heater to keep himself comfortable. https://canadianleaf.wordpress... [wordpress.com]

              Oh, there's all sorts of way to extend winter range dramatically, what you describe being one of the most effective ones. However, since I was replying to someone who was implying the driving conditions to achieve advertised range may be unusual, I felt it would be deceptive on my part to give him the range I can achieve through careful finagling instead of the range I get if I just get in the car and drive without any special considerations.

            • Pre-cooling the interior by turning on the AC while the car is still plugged in also helps with summer range. Many electric cars even let you turn on the heat or AC by remote control, so you don't have to go out to the car to do it.
        • It's not just the cabin that needs to be heated. The battery heating system consumes a fair bit of power on very cold days. You'd think they would heat up enough from just being used to power the car, but apparently heating is still necessary and affects range quite a bit.

        • by teg ( 97890 )

          Worse in the winter cause you're blasting heat? Why not just put a coat on?

          Because cold adversely affects batteries [72.10.52.249], also on electric vehicles [extremetech.com].

        • Living in a cold climate, you learn that coats (and hats, boots, and gloves) are not the complete answer to cold, particularly when you're not doing serious physical activity, and when you're in physical contact with a lot of cold things. Cars without heaters (from experience, I've been in cars with heaters that didn't work) are extremely uncomfortable in the winter, despite wearing full winter gear.

  • by sonicmerlin ( 1505111 ) on Friday December 26, 2014 @05:47PM (#48677285)

    Feels like getting upgrades in a RPG. Pretty awesome.

    It's also nice to see actual real world battery density improvements, rather than just hear about it. Of course 31% over 7 years is a lot less than the 7%/year improvement people like to say lithium ion experiences.

  • by WindBourne ( 631190 ) on Friday December 26, 2014 @05:50PM (#48677293) Journal
    While it is obvious that the new batteries will nearly double the range (li batteries double about every 7-8 years), what about the super charger? No doubt the roadster owner should pay for it (which would also include the electricity), but these the guys that helped make Tesla. Without them, tesla NEVER would have gotten off the ground.

    Come on, elon. You can do the super charger.
    • by Anonymous Coward

      it's a combination of improved batteries, lower resistance by improved body pannels, tires with less rolling restatance, better break-pad release, etc.:
      http://www.teslamotors.com/blog/roadster-30

      No word on Superchargers yet.

      • What the hell is a "break-pad"? Oh, you must mean a brake-pad.

      • Owners might want to take a close look at the NHTSA testing of the tires. Generally speaking, lower rolling resistance means less traction, which means less safe when cornering, maneuvering around an accident or animal ahead, or braking.

        • Owners might want to take a close look at the NHTSA testing of the tires. Generally speaking, lower rolling resistance means less traction, which means less safe when cornering, maneuvering around an accident or animal ahead, or braking.

          Sure, although they could have updated the traction/yaw control software to account for the reduced traction as well, and may have done.

          • The traction control system should kick in when the tires _actually_ lose traction. If they programmed it for an estimate of the traction of new tires on dry, clean pavement they're doing it very, very wrong. A TCS is supposed to kick in when one tire hits a patch of ice, or there's sand on the road. It doesn't care what kind of tires there are - any tire is going to slip on ice.

            Note also the engagement of traction control actually reduces the traction available to make a curve or other maneuver, by "wa

            • The traction control system should kick in when the tires _actually_ lose traction. If they programmed it for an estimate of the traction of new tires on dry, clean pavement they're doing it very, very wrong.

              Tee hee. You're hilarious. If they know that there is wheelspin every time they deliver a certain amount of power to the motor when the car is in a given condition then they can achieve better traction by simply not doing that. Just like your PCM's LUT won't deliver simply any arbitrarily high amount of fuel no matter how much it's trained because there are limits built into the code from the factory, a good traction control system will always* avoid putting out more power than it knows the tires can handle

    • Re: (Score:1, Interesting)

      by BasilBrush ( 643681 )

      If the car wasn't built with a supercharger in mind it might not be practical. Charging generates heat, and too much heat causes malfunctions at best and fires at worst.

    • by hey! ( 33014 )

      Am I the only one who read this initially thinking that "supercharger" meant a pump that forces compressed air into an internal combustion engine?

      • Yep. Probably one of a few. Those who have followed Tesla over 2014 know what Superchargers are in the Tesla context. Also, the capital was a giveaway.

  • by roc97007 ( 608802 ) on Friday December 26, 2014 @05:58PM (#48677333) Journal

    I confess, I was not impressed with the practicality of the all-electric concept, and felt it would always be pretty much a rich person's toy. Common in Hollywood and maybe the Silicon Valley and around Wall Street, and maybe Redmond, for bragging rights, but you'd never see one in Omaha.

    The two issues as I saw it were range and charge time. (Cost is also a factor, but cost usually goes down over time.) It looks like Tesla is making a good faith effort to tackle the range issue, and there is some effort being made to reduce the charge time. Good for them.

    It also occurs to me that for self-sufficiency, all-electric vehicles may be an advantage, as electricity could be easier to make and store than methane, for instance.

    • Re: (Score:2, Offtopic)

      as electricity could be easier to make and store than methane,

      Just plug your methane car into a cow, or a politician.

    • Advances in renewables, particularly PV, are what will lead to electric cars going mainstream eventually. When you get to the point that someone's solar panels can cover their entire house's electrical consumption AND charge their car every night there's no more room for argument.

      • Advances in renewables, particularly PV, are what will lead to electric cars going mainstream eventually. When you get to the point that someone's solar panels can cover their entire house's electrical consumption AND charge their car every night there's no more room for argument.

        ....as long as you have no intention of going car_range/2 further from your house... Otherwise you're still looking at a commercial infrastructure.

        • by dgatwood ( 11270 )

          ....as long as you have no intention of going car_range/2 further from your house... Otherwise you're still looking at a commercial infrastructure.

          Or a generator pod on a small trailer.

          • ....as long as you have no intention of going car_range/2 further from your house... Otherwise you're still looking at a commercial infrastructure.

            Or a generator pod on a small trailer.

            That runs on gasoline! That's brilliant! You could fill up anywhere!

            No, wait...

            • by dgatwood ( 11270 )

              They can be a great option for folks who only occasionally travel long distances, because 98% of the time, you're not dragging the extra weight of an ICE around, and you're (ostensibly) using clean energy to power your car, and you only use gasoline when you're traveling too far for electric cars to otherwise be practical. For people who drive long distances regularly, obviously a hybrid or even a traditional automobile would be a better choice (less pollution, better emissions controls, and better fuel e

              • by dgatwood ( 11270 )

                Unless you're complaining that gasoline stations are a commercial infrastructure, in which case I interpreted that bit to mean electrical infrastructure.

            • How about straight vegetable oil?
  • by Maxo-Texas ( 864189 ) on Friday December 26, 2014 @06:00PM (#48677345)

    4 years after you bought it, it was up to 500 mile range and getting 50 mpg.

    The range increases must partially also translate to the "refill cost" so it's gotten less expensive to drive over time.

    Impressed-- range of electric cars was the main challenge factor (until the recent gasoline price drop).

    Electric at 12c/kwh runs about 1/4 the cost of gasoline at $3.50 ($3.50/100 miles vs $14/100 miles). My electricity runs 10.3/kwh and houston gasoline is down to $1.99 here (Waxahachi has $1.91 gasoline as of 12/21).

    So about $3/100 miles electric and $8/100 miles gasoline right now.

    Apparently you do NOT want electric cars in Hawaii (something like 27c/wkh).

    It doesn't take many electric cars to kill 1% of oil demand and cut $40 to $50 per barrel off the top price for a barrel of oil.

    • Since the significant improvements listed here seem to involve hardware refits - there's no reason a gasoline-powered car couldn't do this.

    • by karnal ( 22275 )

      Does this still look different when Hawaii gas prices are still $3.21 a gallon though? reference --> http://www.hawaiigasprices.com... [hawaiigasprices.com]

      Looks like (@ 30mpg) still close to 11$/100 miles for gasoline in Hawaii; wheras maybe $9/100 miles on electric (taking your figure *3, which is higher than "actual")

      Not as much of a difference, but still a net savings.

      • And with the range improvements, you're not limited to a single trip around the circumference of the Big Island.

      • What is actual electricity in Hawaii now? I was told 27 cents by a Hawaiian on another discussion board-- it sounded really high but I figured imported coal/oil or something was a factor.

    • It doesn't take many electric cars to kill 1% of oil demand and cut $40 to $50 per barrel off the top price for a barrel of oil.

      I hope you weren't being silly enough to suggest that electric cars are what caused oil/gasoline prices to collapse recently?

      • Totally- not at all. But part of the reason for lower demand? Sure.

        I'm sure there are many components to the lower demand and the higher supply.

        Three are roughly 600,000 to 700,000 hybrid electric cars (so about 325,000 gallons a day of gasoline not used) and about 70,000 purely electric cars (so about 140,000 gallons a day of gasoline not used). So purely electric and electric/hybrid cars have reduced demand for gasoline by roughly 465,000 gallons of gasoline per day.

    • 4 years after you bought it, it was up to 500 mile range and getting 50 mpg.

      Well, you're not going to get that big an improvement, but you can often chip for efficiency and gain a few MPG at the expense of a few HP. Often it's actually a very good trade. Until recently when the mileage targets surged few automakers have truly pursued maximum mileage. Typically, they're too afraid of customer response to truly go all in.

    • by Anonymous Coward

      I *live* in Hawaii, and electric cars are remarkably popular here...

      You don't need to drive hundreds of miles -- the islands are all pretty small.

      Electricity is pretty expensive, but gasoline is even more so
      On Maui, only Costco has gas under $3/gallon. All of the other gas stations are between $3.60 and $3.90.

  • They also have new tires, which improve the rolling resistance coefficient by about 20%.

    Do they mention that the minimum stopping distance has now increased by 20%?

    • Are rolling resistance and traction always directly related?

      • nope. It is a complex formula of ride comfort, noise, tire wear, traction and cost. Low rolling resistance tires number one problem has been bad road comfort.

        • Re:Coincidentally... (Score:4, Interesting)

          by Skippy_kangaroo ( 850507 ) on Friday December 26, 2014 @07:29PM (#48677781)

          >Low rolling resistance tires number one problem has been bad road comfort.

          Which surprises me. I fitted low rolling resistance tyres to my bike and experienced improvements in ride comfort, traction, and significantly reduced rolling resistance (tire wear was increased though as these are technically "racing" tyres). When it is your legs powering the vehicle you can really feel all this. On bikes they achieve the improvements with suppler casing (which increases ride comfort) and softer/suppler rubber (which increases traction and ride comfort but decreases tire life).

          (And why is it that people assume that low rolling resistance has anything to do with the coefficient of friction and traction?)

        • by AK Marc ( 707885 )
          With minor tuning in the suspension, goes away. The balance is so complex that most over-simplify because it's easier.
    • They also have new tires, which improve the rolling resistance coefficient by about 20%.

      Do they mention that the minimum stopping distance has now increased by 20%?

      Every year, tires get better. They can probably get the same level of traction with today's LRR tire as what they had before. We bought this year's best All-Terrain (Cooper AT3) which has finally solved their wet traction and tire wear problems, but it still has awful tire noise in turns, makes you think a wheel bearing's going. In a couple more years I expect them to have solved that particular problem. LRR tires have come a long way too, and there's a whole new generation of them now to fit into the space

  • There is a set of speeds and driving conditions where we can confidently drive the Roadster 3.0 over 400 miles.

    On a dry oval course at 20 MPH.

    [ One caveat to the new improvements, once the car goes above 50 MPH, if it drops below that Speed, it explodes. ]

  • is Depends a sponsor?
  • My 1992 Holden Commodore has a Cd of 0.31 so what's all this 0.36 stuff? Bob Pease would be turning in his grave.
    • 2 factors come to mind:

      Sports oriented vehicles often sacrifice Cd to obtain downforce, since top speed is not advertised as heavily or reached as easily in many modern designs.

      Short body length vehicles have less space to adopt Cd optimized forms than longer vehicles. The larger Model S has a claimed 0.24 Cd.

    • Your commodore has a roof. An efficient sedan shape will have attached airflow over most of the the upper surface, with the air possibly leaving the surface halfway down the rear window but rejoining the skin somewhere along the boot (trunk) lid. A convertible loses this laminar flow as soon as the airflow leaves the top of the windscreen. I'm not sure exactly how big the effect is, but it's significant.

    • by Zobeid ( 314469 )

      Several of the Roadster's limitations (and I suspect aerodynamics falls into this category) resulted from the design process, which was basically starting with a Lotus Elise and then modifying, and modifying, and modifying... It imposed a lot of constraints, and Elon Musk later admitted it was a mistake not to design a new vehicle from a blank sheet of paper.

  • Look, it is all well and good. But it is not a car that I could buy. Well, I could, but I don't want to spend that much on a car. Want a decent car for 40K. All these improvements, will it speed up the release of the alleged 40K model?
    • All these improvements, will it speed up the release of the alleged 40K model?

      If people buy the kits, and they probably will, it will help to keep Tesla afloat long enough to release it.

  • I was surprised by the .36. When Lexus first came out c. 1990 they advertised the LS400 heavily as having a .28 and later models got down to .24. .36 is 50% worse than a 1990's sedan and surprising since range has always been an issue.

    I guess it looks cool, though (hard to argue with the company's success).

    • Re:.36? (Score:4, Interesting)

      by sessamoid ( 165542 ) on Saturday December 27, 2014 @12:08AM (#48678595)

      I was surprised by the .36. When Lexus first came out c. 1990 they advertised the LS400 heavily as having a .28 and later models got down to .24. .36 is 50% worse than a 1990's sedan and surprising since range has always been an issue.

      I guess it looks cool, though (hard to argue with the company's success).

      You're missing the part about where this is a roadster. Convertibles have considerably more drag than cars with roofs. Also, you're only looking at Cd. Cd is used in the drag equation to calculate total drag, and the part that isn't part of Cd is surface area. The lexus vehicles have much higher total drag because they're all much bigger cross-sectionally. The Tesla Roadster is tiny.

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