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Tesla owner drives 452 miles on single charge

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Re: Tesla owner drives 452 miles on single charge

#31

Post by kalleboo »

waitwhatt wrote: post #29
mdasen wrote: post #25

Earlier quoted context omitted.

Wouldn't switching to neutral increase fuel usage? When you're in gear, the engine is kept moving by the momentum of the car. When you switch into neutral and break the connection between the movement of the car and the engine, the vehicle has to use fuel to keep the engine moving and not stall. Yes, resistance will cause you to slow down quicker in gear than in neutral, but during that time you should be using basic…

No. The Model S will break the car for regen purposes if you are in gear. So you will lose speed but get a tiny bit more energy added to the battery. It's better to just go into neutral because that whole process is inefficient.

I haven't had the privilege of driving a Tesla, but I have driven a Volvo prototype electric car[0] and it had two modes. One "emulate a petrol car" mode where letting off the accelerator would simulate engine braking (via regen). Then it had a "highway mode" where letting off the accelerator would just coast as if it was in neutral. The highway mode meant you could avoid wasting your momentum on a highway due to slight foot movements in speed regulation.

Do Tesla cars have something like this?

[0] http://www.plugincars.com/volvo-c30-electric

Re: Tesla owner drives 452 miles on single charge

#32

Post by jrockway »

001sky wrote: post #13
dublinben wrote: post #4

Earlier quoted context omitted.

24mph is an excruciatingly slow average speed for a 450 mile journey. No wonder they were able to be so efficient.

so, basically slower than a pro on a bicycle nice one

Also a lot less energy efficient. They claim 171Wh per mile, that's 147 kcal per mile. On a recent 17 mile ride, I applied 591kJ (141 kcal) of work to the bicycle. So a bicycle ridden by a non-pro is almost 18x more energy-efficient than the car. (Of course more than 141 kcal of energy is required to get your muscles to do 141 kcal of work on the pedals. But not 2500 kcal worth, like the car would require. I wish a 1 hour bike ride burned 2500 calories.)

Re: Tesla owner drives 452 miles on single charge

#33

Post by asdfkajh2 »

jrockway wrote: post #32
001sky wrote: post #13

Earlier quoted context omitted.

so, basically slower than a pro on a bicycle nice one

Also a lot less energy efficient. They claim 171Wh per mile, that's 147 kcal per mile. On a recent 17 mile ride, I applied 591kJ (141 kcal) of work to the bicycle. So a bicycle ridden by a non-pro is almost 18x more energy-efficient than the car. (Of course more than 141 kcal of energy is required to get your muscles to do 141 kcal of work on the pedals. But not 2500 kcal worth, like the car would require. I wish a 1…

Of course a bicycle that is what... 1.2x human weight... is more efficient than a car that is probably ~10x human weight, when you measure it by vehicle rather than kcal per mass.

Re: Tesla owner drives 452 miles on single charge

#34

Post by kennywinker »

asdfkajh2 wrote: post #33
jrockway wrote: post #32

Earlier quoted context omitted.

Also a lot less energy efficient. They claim 171Wh per mile, that's 147 kcal per mile. On a recent 17 mile ride, I applied 591kJ (141 kcal) of work to the bicycle. So a bicycle ridden by a non-pro is almost 18x more energy-efficient than the car. (Of course more than 141 kcal of energy is required to get your muscles to do 141 kcal of work on the pedals. But not 2500 kcal worth, like the car would require. I wish a 1…

Of course a bicycle that is what... 1.2x human weight... is more efficient than a car that is probably ~10x human weight, when you measure it by vehicle rather than kcal per mass.

The weight of a car is not optional. If I want to move some mass between point a and point b, and I do it by car, I have no choice but to haul along that extra ~10x my weight. Measuring by kcal/mass ignores this practical reality in favour of a more precise definition of "efficiency".

Also if you're riding a bike that weights 1.2x your body weight, you have the wrong bike! Good god!

Re: Tesla owner drives 452 miles on single charge

#35

Post by babo »

ferrari8608 wrote: post #26
feld wrote: post #3

I commented in another similar post but it seems to be lost... My friend did 438 miles with his P85 by drafting behind a semi the entire trip. With the extra range (efficiency!) of the P85D I'm certain he could have hit 500, easy. I don't recall how many Wh/mile he was doing but it was crazy low. I'm not sure why he hasn't been contacted about his drive, but Tesla does have the data and he's asked a couple engineers…

Truck drivers really don't like people driving close enough behind them to be in their slipstream. If you're that close, they can't see you.

They do this themselves, at least in Europe. It's scary like hell that they follow each other, neck by neck, hour by hour with the shortest possible tracking distance.

Re: Tesla owner drives 452 miles on single charge

#36

Post by eridius »

babo wrote: post #35
ferrari8608 wrote: post #26

Earlier quoted context omitted.

Truck drivers really don't like people driving close enough behind them to be in their slipstream. If you're that close, they can't see you.

They do this themselves, at least in Europe. It's scary like hell that they follow each other, neck by neck, hour by hour with the shortest possible tracking distance.

But can't they also talk to each other over CB radio? Seems like that would make it safer. And of course it's a lot easier to see a truck right behind you than it is to see a car.

Re: Tesla owner drives 452 miles on single charge

#37

Post by dclowd9901 »

kennywinker wrote: post #34
asdfkajh2 wrote: post #33

Earlier quoted context omitted.

Of course a bicycle that is what... 1.2x human weight... is more efficient than a car that is probably ~10x human weight, when you measure it by vehicle rather than kcal per mass.

The weight of a car is not optional. If I want to move some mass between point a and point b, and I do it by car, I have no choice but to haul along that extra ~10x my weight. Measuring by kcal/mass ignores this practical reality in favour of a more precise definition of "efficiency". Also if you're riding a bike that weights 1.2x your body weight, you have the wrong bike! Good god!

Don't know if you were kidding but I think the implication was the combined mass was 1.2x your weight. Of course even then, that's still a pretty heavy bike (I think my commuter clocks in at about 10% of my weight)

Re: Tesla owner drives 452 miles on single charge

#38

Post by Hermel »

hkmurakami wrote: post #2

The (imo, more interesting) stats in the video are missing from the article text body: Total Distance: 728.7km, 452.8mi Total Energy: 77.5kWh Average Energy: 106Wh/km, 171Wh/mi Driving Time: 18:40 hours Average Driving Speed: 39.0km/h, 24.2mph Total Stops: 1 hour Total Time: 19:40 hours Max Elevation: 94m, 310ft

It is obviously the speed that makes the difference. This guy only got about 110 miles (180 km) out of a fully charged 85 kWh Tesla, driving on the German Autobahn at 160 km/h:

http://www.teslamotorsclub.com/showthread.php/32873-Discharg...

Re: Tesla owner drives 452 miles on single charge

#39

Post by dclowd9901 »

ferrari8608 wrote: post #26
feld wrote: post #3

I commented in another similar post but it seems to be lost... My friend did 438 miles with his P85 by drafting behind a semi the entire trip. With the extra range (efficiency!) of the P85D I'm certain he could have hit 500, easy. I don't recall how many Wh/mile he was doing but it was crazy low. I'm not sure why he hasn't been contacted about his drive, but Tesla does have the data and he's asked a couple engineers…

Truck drivers really don't like people driving close enough behind them to be in their slipstream. If you're that close, they can't see you.

Should I be concerned they can't see me when I'm behind them? I can brake quicker than they can and they can't really do anything negative toward me aside from braking hard. Really, you're assuming all the risk. If something happens up ahead you're going to be totally unaware (the main danger of following closely).

Re: Tesla owner drives 452 miles on single charge

#40

Post by dclowd9901 »

mdasen wrote: post #25
limaoscarjuliet wrote: post #19

I read an article on hypermilers the other day. They indeed can push the MPG in high double digits (e.g. 70MPG in accord) but... the approach is not very practical: - Switch to neutral and roll as much as you can, - Drive only in optimal range, - Close the windows, - Do not run A/C or radio, - Do not run lights, - etc. Needless to say they annoy pretty much everybody on the street who is around them. So yes, good res…

Wouldn't switching to neutral increase fuel usage? When you're in gear, the engine is kept moving by the momentum of the car. When you switch into neutral and break the connection between the movement of the car and the engine, the vehicle has to use fuel to keep the engine moving and not stall. Yes, resistance will cause you to slow down quicker in gear than in neutral, but during that time you should be using basic…

Depends how new it is and the car. Older cars still fueled the engine either way. Newer ones cut the fuel themselves, as you intimated.
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