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Tesla Roadster Update Extends Range
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.
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.
I don't read AC A human right
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.
fencepost
just a little off
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.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
"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.
Warning: Opinions known to be heavily biased.
>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?)
The difference is that I can charge at home overnight to a full battery in my garage and I spend 5 seconds plugging in at night and 5 seconds unplugging in the morning. The beauty of it is that I don't need to go to a filling station except on long trips.
As more and more charging stations go in, most charging will happen at home and/or work where charging time doesn't matter.
This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
Because the price is set by the last 1%.
If we can get 99% of our oil out of the ground for $40 per barrel and 1% of our oil out of the ground for $100 per barrel- then every barrel sells is if it cost $100 per barrel to get out of the ground.
And that's just in the united states. Europe also has a similar size fleet of electric vehicles.
And in Europe, for instance, while total petroleum consumption averaged over 15.3 million barrels per day in 2009, it was under 14.3 million in 2013, and has dropped further since.
We get 19 gallons of gasoline per barrel so that's so 465,000 fewer gallons of oil here (and another 465,000 fewer gallons of oil in europe) translates to 48,000 barrels a day of oil that used to be needed that isn't needed any more.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
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.
"No, no, no. Don't tug on that. You never know what it might be attached to."