Accuracy of Long Term Average M/KWh on Dash?

[Stoaty]

I am beginning to wonder if the Long Term Average M/KWh shown on the dash is accurate. I have 1400 miles on my Leaf, and have not reset the M/KWh since the time I took delivery. The first 60 miles going about 50-55 MPH on the freeway, I got 5.3 M/KWh. After that, my average fairly quickly climbed to 5.6 over the first 500 miles or so. Despite the fact that I believe I am driving pretty much the same, the average has slowly increased first to 5.7 and then a week ago to 5.8. To raise the long term average, I would have to be getting higher than 5.8 M/KWh, which seems unlikely given that my daily commute includes about 1300 feet of elevation gain (and loss). The highest number I recall seeing reported on MNL was someone who drives pretty much on the flat and managed about to get about 6.2 M/KWh.

Does anyone else wonder whether this number is correct when not reset for many, many miles? Other thoughts?

 

[evnow]

I am beginning to wonder if the Long Term Average M/KWh shown on the dash is accurate. I have 1400 miles on my Leaf, and have not reset the M/KWh since the time I took delivery. The first 60 miles going about 50-55 MPH on the freeway, I got 5.3 M/KWh. After that, my average fairly quickly climbed to 5.6 over the first 500 miles or so. Despite the fact that I believe I am driving pretty much the same, the average has slowly increased first to 5.7 and then a week ago to 5.8. To raise the long term average, I would have to be getting higher than 5.8 M/KWh, which seems unlikely given that my daily commute includes about 1300 feet of elevation gain (and loss). The highest number I recall seeing reported on MNL was someone who drives pretty much on the flat and managed about to get about 6.2 M/KWh.

Does anyone else wonder whether this number is correct when not reset for many, many miles? Other thoughts?

That doesn't look too accurate. Is this on the dash above the steering wheel or the one on the cenral console ? You can compare one with the other - they are usually within 0.1 m/kwh of each other.

 

[Stoaty]

That doesn't look too accurate. Is this on the dash above the steering wheel or the one on the cenral console ? You can compare one with the other - they are usually within 0.1 m/kwh of each other.

Sorry, I should have been clearer. This is the one on the dash above the steering wheel. I haven't looked at the one on the central console, since I stopped clicking OK for carwings. For the time I was doing it, carwings reported something like 9.0, which I figured was a load of cr*p.

 

[evnow]

Sorry, I should have been clearer. This is the one on the dash above the steering wheel. I haven't looked at the one on the central console, since I stopped clicking OK for carwings. For the time I was doing it, carwings reported something like 9.0, which I figured was a load of cr*p.

The one on the center console has nothing to do with carwings. I usually press Status to get the m/kwh - or you can go thr' the zero emission button.

 

[Stoaty]

The one on the center console has nothing to do with carwings. I usually press Status to get the m/kwh - or you can go thr' the zero emission button.

OK, the center console average shows 6.0 M/KWh... less likely than the 5.8 from the dash. Anyone else seeing numbers that are hard to believe? Based on the center console, I could go 144 miles on a full charge, beating Nissan's most optimistic number (for constant 38 MPH). That doesn't seem very likely.

 

[DaveEV]

If you multiply the dash mi / kWh number by 20 (not 24) that seems to be a realistic distance you can get out of a charge. So 5.8 * 20 = 116 miles.

 

[Stoaty]

If you multiply the dash mi / kWh number by 20 (not 24) that seems to be a realistic distance you can get out of a charge. So 5.8 * 20 = 116 miles.

Does that mean that Nissan was less than truthful about the 24 KWh of usable energy in the battery? Or that the dash M/KWh number is wrong?

 

[DaveEV]

If you multiply the dash mi / kWh number by 20 (not 24) that seems to be a realistic distance you can get out of a charge. So 5.8 * 20 = 116 miles.

Does that mean that Nissan was less than truthful about the 24 KWh of usable energy in the battery? Or that the dash M/KWh number is wrong?

Yes.

 

[Stoaty]

Does that mean that Nissan was less than truthful about the 24 KWh of usable energy in the battery? Or that the dash M/KWh number is wrong?

Yes.

As I suspected. :lol:

 

[evnow]

OK, the center console average shows 6.0 M/KWh... less likely than the 5.8 from the dash. Anyone else seeing numbers that are hard to believe? Based on the center console, I could go 144 miles on a full charge, beating Nissan's most optimistic number (for constant 38 MPH). That doesn't seem very likely.

You should reset the dash or console m/kwh and see what you get in future trips (I reset it after every charge) - tha way you can keep track of what you are getting and also understand how much various factors (like speed or elevation change etc) affect the efficiency.

Multiple the m/kwh by 21 and you get the range. There is a thread on that I started sometime back ...

 

[TangoKilo]

On my LEAF I reset the average on the instrument cluster after every full charge. I have not reset the center console number since new (4500 miles ago) and it has settled down to 4.0 m/kwh...

 

[Stoaty]

On my LEAF I reset the average on the instrument cluster after every full charge. I have not reset the center console number since new (4500 miles ago) and it has settled down to 4.0 m/kwh...

Before starting this thread, I didn't realize there was a separate measurement on the center console, and that the resets were separate. Thanks! I think I will reset the Center Console (which I doubt is as accurate as the dash) and monitor it on a per trip basis.

 

[planet4ever]

To me it seems much easier to reset the one on the dash. I record and then reset it and the trip odometer each time I charge. Two buttons to push down close to the charging door release. I guess I'm just lazy.

Ray

 

[evnow]

I reset the center console after each trip and the dash every month.

 

[aqn]

I reset the dash figures (both mi/kwh and average speed), tripmeter, and the center display's mi/kwh every time I charge. I record all those figures, along with starting/ending bars , starting/ending guess-o-meter miles (FWIW), charge duration, etc.

Over 40 charge events so far, with odometer currently at 2018, the dash display's figures averages 3.84 mi/kwh and the center display's figures averages 3.96 mi/kwh.

The dash display's energy economy has displayed a larger number (than the center display) only once.

Are the figures accurate? I have no clue. I don't know whether I'm really getting 3.8-3.9 mi/kwh. However, I can definitely say that the reported figures are consistent with each other (dash vs center display). If you believe one figure, you can safely believe the other one as well.

 

[Stoaty]

Long term average on the center console before reset was 6.0 M/KWh. I reset the center console and drove my usual 45 mile round trip to work and back, and got a figure for that trip of 6.0. Since at least 90% of my driving is the work commute, it looks like the reading is at least consistent. Guess there aren't any problems that I can see.

 

[NosqueakMouse]

I do not own an electric meter (but I'm thinking of buying one), and I would like to know how efficient my car is.
My problem is that all the information I get, both from the car and from Carwings (on-line) is unreasonable.
For example, here are the stats from my recent week (I commute the same route almost every day).

The car says: Carwings says:
Miles Miles/kWh Miles Miles/kWh
7/25 55.6 4.7 54.3 mi. 5.7
7/26 56.0 4.7 54.7 mi. 5.8
7/27 55.6 4.6 54.3 mi. 5.7
7/28 66.9 4.7 65.4 mi. 5.9 (deviation from normal route)
7/29 55.6 4.6 54.3 mi. 5.7

I charged full the night before each commute. If I really averaged 4.6 m/kWh, then my car should be capable, with 24 kWh of available energy,
to run 110 miles, and at the end I should see about 54 miles available at the end of the day. What the car reported, however was about 38 miles.
The Carwings numbers are even more fantastic; according to them I should be getting 136 miles on a full charge, and at the end of the day I should
still have had 80 miles reserve left.

Questions: Why does Carwings think I went fewer miles than the car thinks? And got drastically more miles per kWh than the car thinks? Is it simply making up
numbers? I thought it obtained its information from telemetry from the car itself?

There is a related question concerning the algorithm the car uses to determine how many miles you have left. Several people said it varies according to
current conditions (and driving history?). But there has to be something much more adrift here. I charged full every night, and each morning the car
announced my starting range. The numbers ranged from 102 miles to 121 miles. These numbers are fantasy numbers, unless there are many miles hiding
under the red sections on the SOC. As an example, one morning it started at 106 miles. I drove no further than .3 miles on flat, empty, residential streets,
at 25 mph, pausing for only 1 stop sign, no climate control on at all, and already the range read only 101 miles. That change can't be assigned to
"conditions", which hadn't even occurred yet. Either there is a sensor that is subject to extreme variability, or the calculation of range makes little sense.
Can anyone out there help me out, or must I buy my electric meter?

 

[evnow]

If I really averaged 4.6 m/kWh, then my car should be capable, with 24 kWh of available energy,
to run 110 miles, and at the end I should see about 54 miles available at the end of the day. What the car reported, however was about 38 miles.

Leaf has about 21 kwh of usable battery. So, 4.6 m/kWh means 96 miles.

Ignore Carwings.

 

[planet4ever]

What evnow said.

By the way, if you need to display a table like this:

The car says: Carwings says:
Miles Miles/kWh Miles Miles/kWh
7/25 55.6 4.7 54.3 mi. 5.7
7/26 56.0 4.7 54.7 mi. 5.8
7/27 55.6 4.6 54.3 mi. 5.7
7/28 66.9 4.7 65.4 mi. 5.9 (deviation from normal route)
7/29 55.6 4.6 54.3 mi. 5.7

you should either provide it as an image or put it in a Code block, like this:

The car says:                                Carwings says:
           Miles       Miles/kWh                     Miles      Miles/kWh
7/25        55.6       4.7                           54.3 mi.      5.7
7/26        56.0       4.7                           54.7 mi.      5.8 
7/27        55.6       4.6                           54.3 mi.      5.7
7/28        66.9       4.7                           65.4 mi.      5.9   (deviation from normal route)
7/29        55.6       4.6                           54.3 mi.      5.7

Ray