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Has anyone calculated their miles per KW? I haven't seen any mention of the cost of driving in stealth.

Cheers.
 

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k-sweise said:
Has anyone calculated their miles per KW? I haven't seen any mention of the cost of driving in stealth.

Cheers.
I get about 46 miles per charge which translates into 2.3 Miles/KWH or $0.0826/mile. YMMV.
 

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I'm not getting quite that much per charge. I am in Dallas and we are getting into 90 degree days already, so A/C is running a fair amount.

Are you doing anything "extreme" (very light right foot, coasting, hill mode, etc.) to get that much mileage from a charge?

What would you estimate is outside temperature when you are getting that sort of range?
 

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Mike_D said:
I'm not getting quite that much per charge. I am in Dallas and we are getting into 90 degree days already, so A/C is running a fair amount.

Are you doing anything "extreme" (very light right foot, coasting, hill mode, etc.) to get that much mileage from a charge?

What would you estimate is outside temperature when you are getting that sort of range?
No, but I drive to and from work in fairly heavy traffic so my average speed is around 40 MPH, which tends to stretch the charge further. My route is also pretty flat which helps. The temperature here is generally in the high 60s and low 70s so heat is not really a factor.
 

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Thanks for the reply. Your driving conditions I would guess are probably close to optimal. I have a combination of stop and go at traffic lights and 70 mph+ on freeways. I suspect my car would perform similarly in the same setting.
 

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Tesla recently published a blog entry on Model S battery range here. The interesting factoid for me is that the range of the "300 mile" battery is 350 miles at a constant 50 mph and drops to 250 miles at a constant 70 mph. So speed matters a LOT.
 

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If memory serves, wind resistance goes up with the square of the velocity and is probably a major component of the forces the motors have to overcome while cruising.
 

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I get a consistent 40-42 Miles as well. That's with an average speed of about 45 with few stops, no hills at all and the A/C blasting.
 

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dennis said:
Tesla recently published a blog entry on Model S battery range here. The interesting factoid for me is that the range of the "300 mile" battery is 350 miles at a constant 50 mph and drops to 250 miles at a constant 70 mph. So speed matters a LOT.
I would love to see Fisker's version of that chart. We know some of the data points, but it would be nice to have the full data.
 

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Weird Fishes said:
Why does Tesla's Model S get 250-300 miles per charge while the Karma only gets 40-50?
1. 85 kw vs. 20 kw
2. 3825 lbs vs. 5300 lbs

Another explanation is that the Model S had to be engineered to get 160-300 miles per charge (depending on battery size), since there is no ICE range extender on the Model S.
 

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dennis said:
Weird Fishes said:
Why does Tesla's Model S get 250-300 miles per charge while the Karma only gets 40-50?
1. 85 kw vs. 20 kw
2. 3825 lbs vs. 5300 lbs

Another explanation is that the Model S had to be engineered to get 160-300 miles per charge (depending on battery size), since there is no ICE range extender on the Model S.
Also because the owner of a pure EV with 40-50 mile range is also known as a frequent pedestrian.
 

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dennis said:
Weird Fishes said:
Why does Tesla's Model S get 250-300 miles per charge while the Karma only gets 40-50?
1. 85 kw vs. 20 kw
2. 3825 lbs vs. 5300 lbs

Another explanation is that the Model S had to be engineered to get 160-300 miles per charge (depending on battery size), since there is no ICE range extender on the Model S.
Ah, that's right! I forgot there is no ICE range extender on the Tesla S. Thanks for the answer. :)
 

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Does anybody know, how long it might take to recharge the model S?
 

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Because the Tesla has a giant battery pack instead of a range extender ICE. Totally different design paradigm.
 

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It would be cool if Fisker released a version of the Karma that did not have any ICE, but had a giant battery pack that could go 250-300 miles instead. Especially if that reduced the weight of the car.
 

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RE: M/KWh

Stefan said:
Does anybody know, how long it might take to recharge the model S?
Depends which charger you order (and, of course, which battery size you order and how far you run it down between charges).

Like the Roadster, you can get a special heavy-duty 70 amp 240 volt charger. Actually you can even get 80 amps, for a 20 kW charge rate. (The Karma charger uses less than 15 amps, so that even at 240 volts you're only pulling 3.3 kW: less than a typical electric dryer, electric range, or central air conditioning compressor.)

Here's a quote directly from Wikipedia:
Charging times vary depending on the battery pack's state-of-charge, its overall capacity, the available voltage, and the available circuit breaker amp rating (current). From a high amperage, 20 kW, 240 VAC line, the range can be restored by 62 miles (100 km) for every hour of charging,[4] equivalent to about five hours to fully charge the 85 kWh size battery. With commercial-grade equipment, an 80% charge could be obtained with a 45-minute QuickCharge.
 

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Weird Fishes said:
It would be cool if Fisker released a version of the Karma that did not have any ICE, but had a giant battery pack that could go 250-300 miles instead. Especially if that reduced the weight of the car.
I think you have missed the point that Fisker markets Electric Vehicles with Extended Range, while Tesla markets pure Electric Vehicles. If you want such a car, you can buy it from Tesla. But if you need to go more 300 miles (more realisticly 250 miles) without waiting multiple hours to charge, you can't do it in a pure EV. That is what differentiates EVer's from EV's, and sets Fisker apart from Tesla. Of course the Karma and Atlantic are a lot better looking than the Model S, but that is not how Fisker has chosen to establish its market position.
 

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dennis said:
Weird Fishes said:
It would be cool if Fisker released a version of the Karma that did not have any ICE, but had a giant battery pack that could go 250-300 miles instead. Especially if that reduced the weight of the car.
I think you have missed the point that Fisker markets Electric Vehicles with Extended Range, while Tesla markets pure Electric Vehicles. If you want such a car, you can buy it from Tesla. But if you need to go more 300 miles (more realisticly 250 miles) without waiting multiple hours to charge, you can't do it in a pure EV. That is what differentiates EVer's from EV's, and sets Fisker apart from Tesla. Of course the Karma and Atlantic are a lot better looking than the Model S, but that is not how Fisker has chosen to establish its market position.
No, I didn't miss the point. (But thanks for the explanation.) I was just saying that it would be cool if Fisker were able to offer both types of vehicle...EV and EVer...in the same gorgeous skin. Perhaps someday they'll be able to do that.

And maybe someday Tesla will be able to offer EV vehicles as beautiful as the Karma! :D

(No offense to prospective Tesla Model S owners such as yourself. I'm also thinking of getting both cars.)
 

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Fab, I think with your calc you need to net out the 15% reserve that isn't used for range. So though the battery rating is 20kwh, I think the 'usable' kwh is more like 17kwh (85%), so wouldn't your 46 mile range be more like 2.7 m/kw?

Btw, I drove the Volt mostly on the highway first in all electric then in range extend mode. I got approximately 39.2 miles or so of all electric range, AC going, at an average speed of probably 72mph.
 
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