Guessometer when used in flat driving conditions

[Brightonuk]

I have read how inaccurate the Leaf guessomerter is mostly from the California contingent but I assume that in California the driving means up and down hills.

Does anyone have data on how the guessometer works on the flat?
The Leaf drivers in Florida (I have waited so long to say that) do not have to contend with hills can we rely te guessometer to be more accurate?

 

[oakwcj]

I have read how inaccurate the Leaf guessomerter is mostly from the California contingent but I assume that in California the driving means up and down hills.

Does anyone have data on how the guessometer works on the flat?
The Leaf drivers in Florida (I have waited so long to say that) do not have to contend with hills can we rely te guessometer to be more accurate?

It should be somewhat less inaccurate without elevation changes, but elevation is only one variable that is likely to change over whatever short period the algorithm uses to make its prediction. Others include mph and climate control. The other night I drove two miles to the theater and two miles back home after attending the meeting at Google. It was cold that evening and I had the heater on. The heater uses a lot of energy for the first few minutes. With that short driving history, I charged to 80%. In the morning, the GOM told me my range was 47 miles. This morning, after more typical driving at the end of the day, my range was 83 miles. In both cases, the car was charged to 80% and there were no elevation changes. The GOM's performance is not as good as a stopped clock.

 

[Brightonuk]

OK point taken

Thanks

I will be installing Gary's SOC meter this weekend along with the Horn and LEDs’s and then listen to the wife complain how it ruins the aesthetics of the car

 

[johnr]

Actually I've found the GOM to be reasonably accurate, and useful. Just keep in mind that it estimates based on your recent driving history, so if your driving is fairly consistent or if the remainder of your trip will be in similar conditions and speeds as your trip has been so far, then it will be fairly accurate. Also, in those cases where the estimate is way off (usually due to climbing a hill that I will soon be descending) I have little difficulty visualizing how the estimate will change based on what I'm expecting for the rest of the drive. Maybe it helps to have a certain mindset. YMMV.

 

[DaveinOlyWA]

the GOM is a tool. like any tool, with a little knowledge on its proper use along with the other tools at your disposal, the GOM can provide you valuable information.

like any tool, it can also be abused, misused and misunderstood.

 

[TickTock]

No real hills in Phoenix, AZ and the GOM is not reliable if you take it for face value. In the morning it always (always) over-estimates how far I can go by 25-50 miles (depending on amount of charge and how I drive that day). Maybe I drive poorly, but it cannot seem to remember that overnight. However, once you calibrate yourself to it, it is useful if you don't like constantly calculating your range, since the error does scale with miles remaining. Once you are down to your last 30 miles or so it's close enough.

 

[Herm]

the GOM is a tool. like any tool, with a little knowledge on its proper use along with the other tools at your disposal, the GOM can provide you valuable information.

Nissan could so easily* fix it, just make it use the average efficiency for the last 15 days instead of the last 5 miles.. no it would not be perfect but it would come a lot closer. Actually the Leaf needs two GOMs, one the long term average I just mentioned and the other one an "instantaneous" reading one, going back a couple of minutes so it does not dance around too much. Once a driver sees two GOMs he will understand that lots of things affect the range.

* my guess it's just software

 

[EdmondLeaf]

I like my GOM when it display more miles than needed. Honestly, I drive mostly highway, once number is stable than is accurate IMHO. When you in the city situation a bit different, but together with charge bars are good indicator what to do. I have to play safe no evse in 100 mile radius. It is flat here.

 

[Danal]

I've been reluctant to post this... as I figured I'd be vilified... but the mileage meter in the panel works quite well for me. My wife also understood what it was doing after a couple of sentences of explanation. She's been happy with it ever since*.

Leave the house with a big number; get on the highway and drive 75 or 80, it drops very quickly and then stabilizes. Obviously, that's how far you can go at 75 or 80. Exit the highway to surface streets and drive 35 or 40 and it will go up somewhat slowly. Obviously, it doesn't want to strand you by being too optimistic too quickly... but after a while, it goes back up and that's how far you can go when driving at 35 or 40. And so on.

In short, it works really well for us. And, to the original question, yes, I live in flatland. North Texas to be precise. Less than 100 feet elevation change for hundreds of miles around (with the exception of river or creek valleys, which we tend to bridge).


I am an absolute techno-geek and may build my own SOC meter, and/or track other messages on the CAN buss(es). But this is my inner geek. As a driver, I am quite happy with provided mile meter.





* In fact, it saved her the other day. She had a round trip that was going to be close to total range. She set off on at her usual 80+ MPH. As the miles plummeted, she realized she'd have to slow down a bit to make it. She slowed to 65 and ignored the meter for a few minutes. As it came up to a more sane estimate, she settled on that speed, and made her trip at 65 with no sweat. If she had maintained 80 all the way, I'm pretty sure she would have come up short. She arrived back home in "low" (but not "very low") warning state.

I am unclear if Gary's SOC meter would have saved her.

 

[DaveinOlyWA]

the GOM is far from perfect and changing the parameters of how it computes the range is not going to fix a thing. i mean using a two week history to guess what you are going to do in the next 30 minutes is nuts.

i really do not have a problem with it. its information is used as a guideline only and to be honest with ya, i really only take note of what it says when i start out in the morning since i rarely start with a full charge or an 80% charge.

i determine (no high level math here) at a glance about what my SOC is and base what i can do on the miles/kw reading which i reset every day. its not perfect but i dont have that option so i do what i can. i am comfortable with it

 

[Caracalover]

If you drive consistantly, the meter will be a useful guide.

I use the det as a reminder/guide when driving where I have been before, especially in the mountains. At the summit (4500') of my Sunday drive I am used to seeing a number in the low teens (11 once!) even with 4 bars of energy. Knowing I have to go about three times that distance was unnerving the first time I saw it, but now it is a comfort, in that everything is ok even though the temperature/weather has changed. I use it as a reminder of how much energy I have been using up to that point. Having 10,000 miles on the car I look for battery degradation in that number as well, although I haven't noticed any yet, and I may be looking in the wrong place.

 

[davewill]

The reasons the DTE/GOM gets such a bad rap here are because we get typically get two main kinds of posts involving it. The first are complaints that it isn't accurate (Duh). The second are people trying to point to the DTE as an indication of efficiency, SOC, etc...for instance people saying that since they drove 40 miles and the DTE still says 70 miles, that they can "easily" get over 100 miles, that sort of thing. I do agree that within limits; knowing how driving style affects it, and knowing that there are hidden miles after it claims zero; you can make good use of it.

 

[Aeolus]

Most of my driving is in ECO mode on relatively flat streets with a mixture of 45mph wide arterial streets (some with timed lights) and freeways at speeds less than 65 without using the climate system. The GOM does an OK job of calculating my miles remaining once you figure out what it is doing.

Nevertheless, I tend to figure out what my distance will be and plan to charge somewhere if my range for the day will be greater than around 60 miles with an 80% charge or 75 miles with a 100% before I get back to my garage, then just use the GOM to verify my calculations as I get close to home.

 

[Brightonuk]

THanks for the info guys
I hope Garys SOC offers a little beter insight I will be installing it on the weekend
I do not really have an isse as I have not had to push the car to over 60 miles (yet) but I have only had it for three days............ and I luv it

 

[Caracalover]

THanks for the info guys
I hope Garys SOC offers a little beter insight I will be installing it on the weekend
I do not really have an isse as I have not had to push the car to over 60 miles (yet) but I have only had it for three days............ and I luv it

I have had mine for almost 10,000 miles, and I still love it! Glad to hear you are happy.

 

[walter]

I took my leaf out the other day for about a 50 mile round trip. I had 100 miles showing on my gauge and the temperature was 52 degrees. I live in coastal North Carolina, no hills and no overpasses. The route is a mix of speeds 40mph to 60mph. I started driving and noticed after going 4 actual miles I had lost 20 miles of energy and this was at 45mph. I finally decided to return home after going 12 actual miles and a loss of HALF my energy. Had I tried to return home the same way I would have turtled somewhere close to my home. Fortunately I had another route to come home. This route was longer but speeds never exceeded 45mph and there were a number of turns and stop signs with a couple of lights along the way. I proceeded back with 50miles of energy and arrived home with 53 miles of energy. The regenerative braking worked great and I for one was thrilled. I have never broken down a road with a car in 40 years and this was not going to be my first. I know driving habits can effect your mileage but this was a complete surprise. I still love the car and have no intention of getting rid of it. I'm just wondering how many charging stations will be needed for long distance travel, too many to mention I fear. This is great technology but unfortunately the infrastructure is at least 10 to 15 years away to help alleviate range anxiety. :|

 

[TonyWilliams]

Unfortunately, it appears that you're basing all your "range" data on the GuessOmeter, which we all know to be a little crazy. The symptom you noticed, drive a couple of miles, then see some abnormally large drop in GOM range is... normal.

You did not "lose" any power, and no doubt could have completed the 50 mile trip. Please check out the chart in my signature line labeled "How Far can I Drive".

Congratulations on your new car.

 

[Brightonuk]

The wife made me laugh.. I said I would like to go to a Ca meet but it would take a month to get there in the Leaf.

 

[Herm]

she is giving you a hint

 

[planet4ever]

I started driving and noticed after going 4 actual miles I had lost 20 miles of energy and this was at 45mph. I finally decided to return home after going 12 actual miles and a loss of HALF my energy. Had I tried to return home the same way I would have turtled somewhere close to my home. Fortunately I had another route to come home. This route was longer but speeds never exceeded 45mph and there were a number of turns and stop signs with a couple of lights along the way. I proceeded back with 50miles of energy and arrived home with 53 miles of energy.

As Tony suggested, you should ignore the crazy big number. It is not telling you how much energy you have. It is trying to predict the future, and doing an abysmal job of it.

Do look at the chart he points to at the bottom of his post. It has lots of good information in it. If nothing else, carry away one fact from that chart: When you get down to five blue-and-white bars (the top bar showing is below the top of the "fuel pump" picture) then your battery has half its maximum energy.

Actually, your original route might well have been better than the one you took home. Turns and stop signs and red lights hurt your economy. Driving at a steady 45 mph is very efficient. If you haven't found it yet, change the "Trip Computer" in the middle of the dash to show you "Energy Economy". That will give you a very good idea of your instantaneous and average economy. This is described in the owners manual under the odd heading "Dot matrix liquid crystal display".

Ray