Range

mogur said:

Oh, and by the way, you got the quote wrong ... I said 65 or 70, not 75.

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Do you really think it would take a long time to slow down from 75 to 55?.. and why are you guys driving 75 on the right hand lane?

I did almost get killed on the autobahn doing about 65.. but the other guy was doing well over 100.. I lost my right side mirror.

I commute 63 hilly miles (1500 feet elevation change) one way with my Leaf, with about 44 miles of it at 55 to 60 mph and 8 miles at 65mph. Charge to 100% at work and get home with one to two bars no problem. If you can charge at work, I wouldn't stress. The Leaf can do it pretty easy.

This kind of article we don't need.
The drivers here were idiots for driving their Leafs 65 miles one way without knowing for sure whether they could charge at this conference. The negative conclusions about the practicality of the Leaf are unwarranted, IMO. As stated repeatedly in this thread and others, the Leaf is not practical for everyone, but if you plan right or if you have an ICE car too, it is very practical for a driver with short distance driving needs. I've only had mine a week but so far no problems with the range.

Lopton said:

You may be right, but guess what, on the California roads there are plenty of slow people in gas cars, and they don't get crushed from behind constantly... contrary to this crazy perception that you will get killed on the freeways of California unless you drive 80, I routinely find traffic flowing between 55 & 65 in the right two lanes. As far as I am concerned there is a golden rule of traffic "Slower traffic stay to the right" If you drive 55 get to the right and be happy, if you drive 85 get to the left and be angry when someone slows you down or gives you a ticket, your choice (I don't care what you choose)
-Matt
PS: My choice is to drive the speed limit (or right lane traffic speed) to save a little energy and not have to pay traffic fines, but anyone is entitled to drive as they want....

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+1! :mrgreen:

Bassman said:

I commute 63 hilly miles (1500 feet elevation change) one way with my Leaf, with about 44 miles of it at 55 to 60 mph and 8 miles at 65mph. Charge to 100% at work and get home with one to two bars no problem. If you can charge at work, I wouldn't stress. The Leaf can do it pretty easy.

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How many years do you think Leaf battery will last (i.e. degradation less than 20%) with 2 full charges per weekday ?

If he is leasing, he probably doesn't care... It seems like he could get by with two 80 percent charges, however...

evnow said:

How many years do you think Leaf battery will last (i.e. degradation less than 20%) with 2 full 100% charges per weekday ?

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Nope, I purchased, but I'm willing to take a chance on the range degradation. I'll be one of the first to look at for any battery dgradation. Even with a 20% loss in range though, I'd still make it to work and back. Hopefully by that time, an L3 will be around.

This might help:

http://www.mynissanleaf.com/viewtopic.php?f=31&t=4295

mogur said:

You might want to take physics 101 again...[ ] it takes much longer to slow from 75 to 55 than from 20 to 0...

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OK, you got me. As I understand it, both cases require you to accelerate some mass (in the minus direction) to a speed change of 20 MPH. Newton told me that with no force on the object it just goes along as is, and it doesn't even matter if it's relative to the ground or relative to the car I'm approaching. So please save me from taking phys 101 again and tell me what I missed. In exchange, I'll remind you that both the air and the road are standing still, which means my brakes will have an advantage at 75 (lots of regen) and my car will, also, with all that air resistance. Those would tip the balance, if the original proposal turned out to be a wash.

gbarry42 said:

...please save me from taking phys 101 again and tell me what I missed...

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It is about the energy that must be transformed.

kinetic energy (K) = 1/2 mass * velocity^2
mass = Curb weight of a Leaf 1521 kg (3354 lb)

K for v of 75MPH = 854.9 kJ (kilojoules)
K for 55MPH = 459.7 kJ
Delta K(75-55) = 395.2 kJ

K for 20MPH = 60.8 kJ

K(75-55) = 6.5 * K(20)

Yes much more deceleration is needed to go from 75MPH to 55MPH than 20MPH to 0. Friction will be a bigger factor at higher speeds too.

I see where the issue is. But now I need to know how much energy is dissipated in the brakes at 20 MPH vs 75 MPH; it's going to involve friction and speed. Remember, the conjecture was about how long it took, not how much energy was required.

Then, after we're done here, I might have to claim that maybe we didn't get into this until physics 102...

patrick0101 said:

Yes much more deceleration is needed to go from 75MPH to 55MPH than 20MPH to 0.

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Aren't we forgetting that the amount of kinetic energy an object contains is relative?

As gbarry reminded us (us Encinitas folk gotta stick together! ) the question was related to how long it'd take to decelerate 20 mph.

Since F = M*A and we are accelerating the car the same relative amount, the force (limited by amount of friction between the tires and road) it takes to do so (and thus the time) is the same.

By definition:
Acceleration = (Start speed - finish speed) / time

Which tells you that if you apply the same force (assuming your tires have the same grip/friction at 75 mph as 20 mph) the amount of time is the same. Of course - you will travel a lot farther during that time!

Your typical car will exert about 1g under braking from top speed down to a stop.

Not explained very well - but I hope the point is made.

davewill said:

mogur said:

Not to the average ICE driver that sees one going slowly on the freeway and thinks, "There goes another one of those damn electric cars that can't keep up with anything or go anywhere - I'll never buy one of those!" They have no idea where you are going or coming from, or what you are doing and thinking; just that you are simply slow... Perception is reality to the uninformed...

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Well, I'm not going to waste energy just for PR.

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What's worse for PR - driving with the slow traffic on the highway - or draining it and sitting on the side of the road while waiting for a tow truck?

drees said:

What's worse for PR - driving with the slow traffic on the highway - or draining it and sitting on the side of the road while waiting for a tow truck?

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There is no bad PR by driving 55 on the right hand lane.. its a normal driving speed and lots of people do it. It is bad form to do the same on the high speed lanes, forcing people to pass you on the right is unsafe. A speed differential of 20mph is nothing.

Couple of issues here with driving at 55 on the fast lane- the carpool lane is on the left and when you drive at 55 you get stared at, people ride right up your rear and in some extreme cases, overtake you and cut you off when they are getting back.


Anyway- i wanted to report inconsistencies with my range after a full charge. I have owned the car for less than a week and i notice the range after a full charge is different each time. My drive has been mostly consistent on the freeway.

Day1: Eco mode showed 96 miles.
Day2 ECO mode showed 90 miles
Day 3 eco mode showed 100 miles.

I am charging 100% in all the cases above. of course, in practice i see the results are more or less consistent. today i drove 39 miles in some moderate hilly terrain, on the freeway and the range shows 68 miles left. My average speed was 40mph on the freeway while i drove quite some distance at 55-60 range.

trojanm50 said:

Anyway- i wanted to report inconsistencies with my range after a full charge.

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There's a reason we call it the guessometer. Anyway, those differences are probably due to inconsistencies in your efficiency on the drive home the night before.

1. Do not believe the range number. It is a guess.
2. It will be lower if the climate control is on.
3. Don't believe the number.
4. It changes, based on the recent miles/kilowatt-hour number
5. Oh, yes, and Don't believe the range number.

You'll stay more sane if you watch the "bars" (though they are crude, too), and the amount of juice it takes to charge back up. If you have Blink EVSE, it will tell you kWhr directly. If you have something else, use the time it takes to charge as an approximation.

drees said:

Of course - you will travel a lot farther during that time!

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Yes, but the vehicle you are approaching will travel a lot farther, too! (Farther than the one at 0 MPH)

2400 miles and climbing... Personally, I pay attention to the bars. The estimated numerical range indication is for "entertainment purposes only"...

TangoKilo said:

Personally, I pay attention to the bars. The estimated numerical range indication is for "entertainment purposes only"...

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That may be, but I still LOVE seeing 108 miles after an 80% charge. :mrgreen: