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Driving range drops from 250 miles to 200+ miles

Tesla Motors has been touting its impressive Roadster for quite some time now. The $100,000 sports car boasts impressive specs including a top speed of 130MPH and the ability to accelerate from 0 to 60MPH in just 4 seconds. At the time the Tesla Roadster was first announced, the vehicle was projected to have a range of 250 miles thanks to its 6,381 cell lithium-ion battery pack.

Tesla Motors, however, has just informed its customers who have already put a down deposit on the vehicle that the driving range will come up short. The company can no longer guarantee the 250 mile range after extensive on-road testing. Instead, the EPA certified range of the vehicle is expected to be "greater than 200 miles."

Darryl Siry, VP of Marketing for Tesla Motors, cites a number of reasons for the decrease in driving range. Changes have been made to improve the safety of the battery pack, lower capacity lithium-ion cell had to be used to increase durability and added weight to the chassis to the tune of several hundred pounds have also hindered performance.

"The original premise of this groundbreaking car was that its range would be high enough that you would not have to worry about charging during a typical day, even if you have a long commute, take the car out for dinner and chores, or even take the scenic route home," said Siry. "Once home, you plug it in - just like you would your cell phone - and by the time you're ready for another day, your Tesla Roadster is fully charged and ready to go. We believe that this premise is still intact with a range above 200 miles."

For more information on the development of the Tesla Roadster, you can check out a recent interview with Tesla Motors CEO Martin Eberhard at AutoblogGreen.

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By slawless on 4/18/2007 12:01:20 PM , Rating: 4
I still wonder what the true range will be when it is 20 degrees out at night with snow on the ground.

Under a similar seneiro GMs EV1 droped fron 120 to 12 miles.

Also when the batteries are three years old what will be the range.

RE: surpiise
By Falloutboy on 4/18/2007 12:06:04 PM , Rating: 3
EV1 I'm pretty sure used NIMH batteries the tesla uses Li-on which I don't beleave have as much issue with cold. I also remember reading on there site something about temp control in the battery compartment

RE: surpiise
By stromgald on 4/18/2007 12:12:31 PM , Rating: 3
You beat me to it. You're right about the EV1's battery being either lead-acid or NiMH depending on the version. NiMH is one of the most suceptible batteries to low temperatures. LiIon is better, but isn't great either. I think lead-acid and Nickel Cadmium batteries (which are used on many satellites) are the best, but they're also much heavier than LiIon.

Here's some info on battery discharge at various temps: .

RE: surpiise
By RamarC on 4/18/2007 12:08:14 PM , Rating: 5
I still wonder what the true range will be when it is 20 degrees out at night with snow on the ground.

I've never seen a Ferrari out in that kind of weather. So I doubt if too many Teslas will be out then either. If you can afford a $100K car, you know when to leave it in garage and drive the Range Rover instead.

RE: surpiise
By therealnickdanger on 4/18/2007 12:33:30 PM , Rating: 1
Haven't you ever seen Viva Bam! He drives his Lambo in the snow, through dirt, whereever. There are people that have money and then there are people that have money .

RE: surpiise
By ChuckDriver on 4/18/2007 2:55:45 PM , Rating: 5
... then there are people who have money but no brains.

RE: surpiise
By othercents on 4/18/2007 4:58:24 PM , Rating: 2
Who needs brains when you have money?? LOL..

RE: surpiise
By Eris23007 on 4/18/2007 6:25:07 PM , Rating: 3
Only the people who want to keep having money for a long time!

RE: surpiise
By jconan on 4/19/2007 1:17:54 AM , Rating: 2
Kirk Kerkorian and Warren Buffet come to mind as people who have tons and tons of greenbacks. They drive common cars not extravagant cars to live comfortably. They're contrary to the statement of people with money and no brains.

RE: surpiise
By mrteddyears on 4/19/2007 5:12:32 AM , Rating: 2
Then why have all that cash to give to the tax man when you die, take the ENZO and go off roading across sand dunes.


RE: surpiise
By Hoser McMoose on 4/18/2007 3:34:10 PM , Rating: 2
As you say, it's probably not such an issue with this model. Let's not forget that this is a convertible as well! As someone who lives in a climate that occasionally sees temperatures bellow -30C, let me tell you, you don't see too many soft-tops around on those days! Even with the top up it's just not a very viable option!

However this is definitely something to consider if/when we start looking into other electric or plug-in hybrid vehicles. Eventually the idea is to make them true replacements for standard ICE based cars. If they aren't going to work properly at -40C then they just aren't going to sell in this neck of the woods at least. It might only get that cold one or two nights of the year, but those are the times you REALLY want your car to be working if you have to leave the house at all!

RE: surpiise
By Chernobyl68 on 4/18/2007 3:50:44 PM , Rating: 2
ever been to lake tahoe?

RE: surpiise
By othercents on 4/18/2007 5:02:34 PM , Rating: 3
I am very surprised at the number of electric vehicles that are at the auto shows that wouldn't ever be able to run in the snow. These three wheeled inventions that run on motorcycle tires just won't cut it no matter how good the MPG is.

The majority of people (myself included) have one vehicle to run both summer and winter. We need vehicles that will work in all types of weather. My Altima barely made it through the Colorado snow storms which makes me think I should have purchased another truck.


RE: surpiise
By Hoser McMoose on 4/19/2007 12:02:00 PM , Rating: 2
By far the biggest factor in driving in snow is the tires. Everything else to do with the car is secondary. I drive an Altima as well, and with a good set of winter tires it'll handle driving in the snow better than most any truck with summer tires. Actually a rear-wheel drive truck without winter tires is about the worst possible vehicle you can get for driving on snow and ice (all the weight up front + all the power in the rear = no traction). A 4WD truck with winter tires will handle just about anything.

Of course, if the vehicle won't even start in the winter because the motor or batteries won't work in the cold weather, then that's another story altogether!

RE: surpiise
By othercents on 4/20/2007 6:11:25 PM , Rating: 2
BTW. Before my Altima I drove an RWD F150 and did great in the snow even without winter tires. However I did use all terrain tires and I had a manual transmission. My old T-bird was way worse than my Truck ever was.

The problem with the Altima is clearance. I couldn't get in or out of the back streets because the snow was too high. There is also problems on ice with the Altima that I never had with the truck. The truck I can spin the tires and still steer, but the Altima I basically had to keep the tires from spinning just to get it to steer right.


RE: surpiise
By theapparition on 4/18/2007 12:11:54 PM , Rating: 2
My only comment to that, not making any judgement on the actual battery technology, is that no one if going to take out their 50K Lotus out in the snow, so its a safe assumption that this 100K Lotus "knock-off" will not see snow either.

If memory serves, the EV1 used conventional lead-acid batteries, quite a bit different than Lithium-ion.

RE: surpiise
By Polynikes on 4/18/2007 3:10:27 PM , Rating: 2
It may be a "knock-off," but it can get to 60 faster than the Elise. :) I'd wager the Elise handles better, though.

RE: surpiise
By Milliamp on 4/18/2007 3:19:56 PM , Rating: 2
And with a 200 mile range who is going to plan to charge it at 195 miles?

Just like how I usually fill up my car and motorcycle with 30 - 40 miles still left on the tank, I suspect the same will apply for the Tesla.

I am sure the power of the car is reduced as the battery starts to die also, unlike with gasoline.

This means that even new most people will have to charge these at 160 miles or so.

More frequent recharges = lower battery life.

I wonder if they are going to reduce the selling price 20% to match?

RE: surpiise
By Hoser McMoose on 4/18/2007 3:53:37 PM , Rating: 3
I am sure the power of the car is reduced as the battery starts to die also, unlike with gasoline.

The 'power', in terms of how fast it can go, shouldn't be affected much at all. However the amount of charge it holds (ie how far you can drive) will definitely drop in time.

Another problem with this is going to be leaving your car for long periods of time. Li-Ion batteries self-discharge at about 5-10% per month. So for people who want to store this car over the winter it'll probably be half dead in the spring, so some precautions are necessary here. Mind you, it's not a very smart idea to store a ICE car over the winter with a tank full of gas either.

I can't help but think that we need at least one more major advancement in battery technology before electric and even plug-in hybrid cars are going to be really viable solutions for the mainstream.

RE: surpiise
By othercents on 4/18/2007 5:11:16 PM , Rating: 2
Actually as the battery hits the end of it's charge state the voltage starts to drop. The reverse is true too where fully charged batteries have a voltage spike. However Telsa might have taken this into account and will shut the car down after the voltage goes under a certain number and a regulator that keeps the voltage from going above a certain number.

The regulator is important because sometimes a battery can loose all power under load, but still be charged enough to do some things. For example, if you hotrod the car you might loose power, but if you drive conservatively you might make it home.


RE: surpiise
By Hoser McMoose on 4/19/2007 12:09:28 PM , Rating: 2
I'd say that it's pretty much a guarantee that they've taken this into account if they want to make the vehicle remotely reliable and safe. These kinds of problems aren't that difficult to tackle (conceptually at least) and when you're dealing with 250kW worth of electrical motors, you want to be pretty certain that you're voltage isn't going to be going up and down all willy nilly on you!

The spike and drop in voltage is more an issue in $1-$200 consumer electronic products where safety and reliability aren't big concerns. In a $100,000 automobile it's a different story.

RE: surpiise
By Zoomer on 4/18/2007 3:56:59 PM , Rating: 2
False, they'll just have a lower range.

Obviously, they'll have voltage regulators in this.

RE: surpiise
By thartist on 4/18/2007 3:47:01 PM , Rating: 1
...and what's the electricity bill after using one of these? maybe 200"k"+ ?

RE: surpiise
By Hoser McMoose on 4/18/2007 4:29:02 PM , Rating: 2
A full battery charge is 56kWh. Assuming a bit of loss in the system (not much, Li-Ion are pretty efficient in this regard), you're probably looking at about 60kWh worth of electricity per charge.

Typical price for electricity in the US is about $0.10-$0.12/kWh, maybe up to ~$0.16/kWh in California. With those prices you're looking at about $6.00 to $9.60 for a full "tank".

For comparison, the Lotus Elise (same chassis as this electric car, similar performance) is rated for 26 miles to the gallon. 200 miles therefore works out to 7.7 gallons. Current gasoline price is about $2.60/gallon, so those 7.7 gallons would cost you $20. So the electricity is at least twice as cheap as the gas it displaces.

Of course, the Tesla is twice as expensive as the Elise and it's unlikely that any owner is ever going to "make their money back", so to speak, by buying this electric car vs. the gasoline variety.

RE: surpiise
By Steve Guilliot on 4/18/2007 10:56:38 PM , Rating: 1
Buyers of the Tesla aren't concerned about making their money back. They know it's a losing proposition. It's more about the novelty of a high-performance electric car.

We won't see mass adoption until/unless these Li battery packs get below $5000, which is about 1/10th the current price.

My money is on hydrogen (as a fuel, not fuel-cell).

RE: surpiise
By mindless1 on 4/19/2007 4:44:14 AM , Rating: 2
No, you're not looking at 60kWh. Ideals still have to have infrastructure, you have to GET that idealized power from a station to a grid to a home to a regulated level usable for charging.

Also, when more and more people go electric, the typical price for electricity will go up. A lot. There will be more shortages than ever.

RE: surpiise
By Hoser McMoose on 4/19/2007 12:23:29 PM , Rating: 2
I was looking at this from a purely cost perspective, in which case we are looking at roughly 60kWh worth of electricity as seen on the end-users bill and as charged at about $0.10-$0.16/kWh. Anything upstream of the end user simply gets rolled into the cost.

The extra infrastructure required in this equation is the one-time cost of installing a 240V/70amp circuit to your garage (or wherever you want to plug your car in at night). This is going to cost some coin, especially if you need to upgrade your circuit from the pole to your house to accommodate this (a distinct possibility). Only other cost I didn't count is the lawyer fees for when the cops search your house thinking all this electricity use is for a grow op! ;)

As for the cost of electricity, certainly widespread adoption of electric vehicles will trigger a rise in electricity prices and a drop in gasoline prices. However the original question was just about this Tesla car, which will only be produced in ~100 units per year, so it won't have any effect here.

EPA Testing
By novacthall on 4/18/2007 1:27:00 PM , Rating: 2
I'm not sure I buy the 200 mile range figure being published. Is this under ideal driving conditions, with open roads, plentiful sunshine, and San Diego-like outdoor conditions? What happens if you crank the heat on full blast, with the windshield wipers going all out, lights on, and the radio tuned to a weather report? Does your round-trip effective range cut from 200 miles to 180? 150? Less?

Not that I would want to in this thing, but it troubles me that Tesla's new method essentially kills the classic American road trip. 200 miles at a time, Interstate 10 becomes an odyssey (assuming La Quinta will let you plug your car in overnight).

RE: EPA Testing
By maevinj on 4/18/2007 1:39:47 PM , Rating: 4
This isn't tesla's new method , this is the result of the EPA's method and the solutions Tesla did to conform with the EPA"s regulation

RE: EPA Testing
By novacthall on 4/18/2007 2:40:30 PM , Rating: 2
I was not terribly clear on what I meant by "Tesla's new method". I was referring to their drivetrain and powertrain, not the mileage estimates.

Apologies for the confusion.

RE: EPA Testing
By Topweasel on 4/18/2007 4:45:36 PM , Rating: 2
I think that he might not be saying that Tesla really did that much to change the rating, people might be assuming this type of change because the Tesla rating before might have been based on the EPA rating used prior to this year, and that the 50 mile drop would confirm to the pretty much across the board drop in mileage.

Cancel my order.
By Mitch101 on 4/18/2007 11:55:43 AM , Rating: 2
Well that just does it for me. I'm just going to have to cancel my order.

RE: Cancel my order.
By Mudvillager on 4/18/2007 12:00:09 PM , Rating: 2
I can take care of the money you put in if you want.

RE: Cancel my order.
By Mitch101 on 4/18/2007 12:12:25 PM , Rating: 2
Hmm. Giving money to someone named Mudvillager doesnt sound like a good financial decision even if I had that kind of coin.

How do I know you wont invest in technologies like Cray or Straw housing?

RE: Cancel my order.
By crimson117 on 4/18/2007 1:38:18 PM , Rating: 2
Maybe it's magic mud?

By patentman on 4/18/2007 12:20:34 PM , Rating: 2

By Milliamp on 4/18/2007 3:31:58 PM , Rating: 2
To go from the current 200 miles to 250 they would need a ~8000 cell battery becasue they need a 20% increase in power and also have to compinsate for the added weight and support of the new battery.

By Topweasel on 4/18/2007 4:47:26 PM , Rating: 2
Hopefully they don't have Sony fulfilling the orders for those cells.

200 miles
By Quryous on 4/18/2007 6:04:34 PM , Rating: 2
Two hundred miles won't even get me to granpaw's house. So much for any utility. Actually, 250 MIGHT not have made it, either. Right on the margin. Aging batteries and lowered capacity and it certainly wouldn't. If they had made it 300, then with age it would still be reasonable.

RE: 200 miles
By andrinoaa on 4/19/2007 4:29:22 AM , Rating: 2
Why all the negativity towards electric cars? We are just starting on the first step of this technology. Some one has to bring the first one out -Warts and all. It won't be perfect but its a start. All you guys check this site out to see whats coming up in the IT area, you should know better. We need this technology to succeed. By all means point out its shortcomings but why compare it to a camaro 300bhp and 400miles range? Its chalk and cheese. The internal combustion engine has been around for more than 100yrs, battery technology is only now starting to find solutions. Lets all applaud the fact that somebody is actually taking that first step.

RE: 200 miles
By mindless1 on 4/19/2007 4:48:27 AM , Rating: 2
Applauding steps and research does not in any way mean we can't find problems with currently proposed solutions, especially when, like in the case of these article, the manufacturer over optimistically specs range then has to recant later. How about instead of the BS lies to save money, they announced that in appreciation to their loyal customers the range would go UP from 250 to 300? Drivablility and safety are just nonsense lies, it would be ever more "drivable" to continually cut the pack even more then reengineer for the weight distribution again. Safety is no factor, those elements could be in place no matter what the base size of the cells are. If they "goofed" and didn't factor for the size or weight of safe cells, ok, they get to reengineer to accomdate them, instead of just giving customers the shaft.

By codeThug on 4/18/2007 2:46:27 PM , Rating: 3
To hell with the gas mileage. Why doesn't this car have a large toroid on top with 10 foot lightning bolts spewing out?

I want to be able to smell the ozone three miles away...

RE: megavolts
By Zoomer on 4/18/2007 3:58:26 PM , Rating: 2
You'll need Dr. Fusion for that. Unfortunately, these lousy LiIons won't cut it for that application.

By mmcdonalataocdotgov on 4/19/2007 11:33:06 AM , Rating: 2
Running ANY additional services will significantly reduce battery time (that would be radio, A/C, heater, windshield wipers). They all take electricity away from travel time.

By Hoser McMoose on 4/19/2007 12:29:48 PM , Rating: 2
The same is mostly true for a plain old ICE vehicles as well. Running your AC, radio, windshield, etc. all get their power from your alternator which in turn is sapping power from your engine, using more gasoline and reducing the range that you'll go on each tank.

The only exception is the heater, which on an ICE is basically just redirecting waste heat from the engine into the passenger compartment. The only additional energy is for the fans to blow that air in. However this is only about half as bad as the AC in the summer since electrical heaters are basically 100% efficient while AC is no where close.

Too Bad
By RU482 on 4/19/2007 2:14:13 PM , Rating: 2
It saddens me to say it, but I predict this car will be a tremendous flop once its been out there for a while. Sounds like a great car for So Cal or the South East. Everywhere else, the climate range will kill that battery pack.

Id be curious to know the configuration of the battery pack (how many cells in series and parallel). If there are alot in parallel (which there would have to be to get any decent capacity), that pack is doomed to see problems as cells begin to drift.

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