Aero wheels

[richkae]

Just out of curiosity, how do you figure that? Given the cost of electricity, particularly in WA, you won't save enough to make a big difference.

Let's be generous and say .10 per kwh and 85 kwh gets you 300 miles, so you get 3.52 miles per kwh with normal tires. Over 100,000 miles you'll use 28409 kwh. Gaining 5% efficiency means you save 1420 kwh or $142. The 19" aero rims cost $1500. You'd have to drive around 1 million miles to save enough on electricity costs to pay back the aero tires.

Or is there some other valuation I'm missing that would make the aero tires pay for themselves?

70 more miles of range costs $10000
That's $142 per mile.
If the aero wheels give you 15 more miles on the 300 mile pack - that's only $100 per mile.
If they give 11.5 more miles on the 230 mile pack - that's only $130 per mile.

 

[jerry33]

70 more miles of range costs $10000
That's $142 per mile.
If the aero wheels give you 15 more miles on the 300 mile pack - that's only $100 per mile.
If they give 11.5 more miles on the 230 mile pack - that's only $130 per mile.

There is also the small amount of reduced battery wear because not as much power is used at a given speed. Will this increase battery life by 5%, 10%, 0%? Don't know. Not sure we can know until the end of the battery life. However, for trips--and I really want to take a lot of trips with my Model S--every bit of extra range helps. Because I can beat the EPA on the Prius by 17%, I'm hoping that I can do the same on the Tesla. That would give around 375 miles per charge on a trip. As 600 - 650 miles is the distance I like to travel in a day, it should require only one stop for charging, even in very cold weather. Well, that's the goal anyway.

 

[Robert.Boston]

I think that @richkae has the right way to think about it -- if one is willing to pay $10k for a battery upgrade to go ~70 miles further, then the "revealed value" of extra miles is $142/mile. At that price, the $1,500 for aero wheels is a bargain. The larger battery, however, also brings greater performance, a longer warranty, and supercharger access, so it might not be as straightforward as this cost comparison

 

[Dborn]

Picasa Web Albums - Tesla HQ - Wheels
Also posted in error on anther thread, sorry. Photo of what appears to be the definitive aero wheel.


Mod note: Duplicate post deleted. (And thanks for reposting in correct thread!)

 

[jerry33]

Picasa Web Albums - Tesla HQ - Wheels
Also posted in error on anther thread, sorry. Photo of what appears to be the definitive aero wheel.

That's a mock up, not the actual wheel--at least my assumption is that the aero wheel isn't just a hubcap. There may be some differences in the actual appearance.

 

[rlawson4]

I hope so. I want aero wheels but the mock up is seriously ugly.

 

[Robert.Boston]

The aero wheel is definitely on my list of "have to see it to decide".

 

[JRP3]

Because I can beat the EPA on the Prius by 17%, I'm hoping that I can do the same on the Tesla. That would give around 375 miles per charge on a trip.

Tesla's range estimates are not the EPA numbers last I knew.

 

[jerry33]

That's true [Tesla's range estimates aren't EPA numbers], but there aren't any EPA numbers yet.

 

[roblab]

There is also the small amount of reduced battery wear because not as much power is used at a given speed. Will this increase battery life by 5%, 10%, 0%? Don't know. Not sure we can know until the end of the battery life. However, for trips--and I really want to take a lot of trips with my Model S--every bit of extra range helps. Because I can beat the EPA on the Prius by 17%, I'm hoping that I can do the same on the Tesla. That would give around 375 miles per charge on a trip. As 600 - 650 miles is the distance I like to travel in a day, it should require only one stop for charging, even in very cold weather. Well, that's the goal anyway.

I'm with you! I once got 164 miles per charge on my RAV4EV, and I am itching to try my hand (OK, foot) on trying for 400 mi/ch on the Model S. I plan to run up to Canada from Napa Valley, visiting relatives and friends when I get mine. I've already contacted and located all charging spots on the way.

 

[KBF]

For Sigs, you save money by "downgrading" to the aeros over the 21" wheels, since we don't technically pay for them (it's all one big expensive package). Maybe someone can whip up a quick calculation regarding when a Sig holder theoretically "breaks even" by going with the aeros (to address the complaints of those who want a discount for not getting the 21" wheels). Not that most Sig holders really NEED to save that amount of money...

For me, though, it's definitely the increased range that's more important than any $ amount. Oh, and the ability to use winter tires - that's a big deal where I live.

 

[dsm363]

Yeah. 21" rims really make no practical sense for anyone that can't use them all year long (unless they are willing to buy a second send of 19" rims for winter wheels of course and use the 21" wheels for summer).

 

[ckessel]

I think that @richkae has the right way to think about it -- if one is willing to pay $10k for a battery upgrade to go ~70 miles further, then the "revealed value" of extra miles is $142/mile. At that price, the $1,500 for aero wheels is a bargain. The larger battery, however, also brings greater performance, a longer warranty, and supercharger access, so it might not be as straightforward as this cost comparison

I'm getting the larger battery for the reasons you mentioned as well as range. Also, for me, it's about what will get used. I'll use some portion of that extra 70 miles on a regular basis since I have a ~240 mile round trip I do every couple months. I'd probably never use the mileage given to me by the aero wheels. I'd just never be that close to the edge of my range, so the only advantage the aero's would have for me is the energy savings, which is miniscule. Obviously driving needs vary though, so what fits my usage profile doesn't match other folks.

 

[richkae]

For me, though, it's definitely the increased range that's more important than any $ amount.

If you buy the 85kWh model S you have a great car.
If you buy the 85kWh model S with the aerodynamic wheels you have the longest range production EV available.

Do you need it? No, likely not. Just like you don't need to shave another 0.1 second off the 0-60.

 

[richkae]

Here's another thought:
Take a Model S performance with the 21 inch wheels and a Model S 85kWh with the aerodynamic wheels.

The car with the aero wheels will win any straight line race longer than about 130 miles ( maybe even shorter ones too, hard to calculate the exact crossover point )

By this measure, the Model S with the aero wheels is faster.

 

[Trnsl8r]

Picasa Web Albums - Tesla HQ - Wheels
Also posted in error on anther thread, sorry. Photo of what appears to be the definitive aero wheel.


Mod note: Duplicate post deleted. (And thanks for reposting in correct thread!)

Not sure if this was mentioned, but did anyone else notice that the mockup is subtly different from the design studio?

 

[spatterso911]

I think that @richkae has the right way to think about it -- if one is willing to pay $10k for a battery upgrade to go ~70 miles further, then the "revealed value" of extra miles is $142/mile. At that price, the $1,500 for aero wheels is a bargain. The larger battery, however, also brings greater performance, a longer warranty, and supercharger access, so it might not be as straightforward as this cost comparison

And let's not forget a longer life with less cycle time, greater piece of mind with greater range for those with longer commutes or more frequent trips > 100 miles, and less time recharging on even longer trips. Remember, in this world, time = money too!

Far too many variables to just say $142/mile. I still don't see an upside to the aero wheels, unless you are getting the 40 kwh pack. Makes more sense then, but you still are on the downside given the cost of the wheels.

 

[spatterso911]

Okay, as just pointed out. If you are getting 19" wheels anyways, there is an upside.

 

[GSP]

I'm getting the larger battery for the reasons you mentioned as well as range. Also, for me, it's about what will get used. I'll use some portion of that extra 70 miles on a regular basis since I have a ~240 mile round trip I do every couple months. I'd probably never use the mileage given to me by the aero wheels. I'd just never be that close to the edge of my range, so the only advantage the aero's would have for me is the energy savings, which is miniscule. Obviously driving needs vary though, so what fits my usage profile doesn't match other folks.

The Aero wheels would provide more range margin, which could allow more sprited driving, or more comfortable HVAC settings, with the same miles remaining at your destination. The extra range could make up for unexpected cold or hot weather, or rainstorms. Also the Aero wheels could enable crushing at faster speeds on long trips, with the same range between charging sessions.

That is a lot of benefits for $1500

GSP

 

[jerry33]

Sometimes just a few miles is the difference between you arriving and the buzzards arriving. At 03:00 in rural Saskatchewan in January you really, really don't want to be stranded. Life expectancy is about thirty minutes once the heater stops working.