Guess-o-meter calculations. What is your true range and how much you should trust the car's Algo.

fshuk1

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Ok people, get those calculators out.

We know the guess-o-meter calculates your range using some dark-art-algorithm from your previous-recent driving style. That is not what I would like us to calculate. I have an SR car and when full it shows a range from 236 to 254 which clearly is wrong ( but makes me feel good..... it is good to fool yourself sometime).

Anyway, your quest ( should you wish to accept it) is to use some calculations and compare with the results from FROM LAST CHARGE data. So lets say you charge to 100%. Then drive merrily till you get to 20% battery left. Please do the following calculation.

SR has 50.8 KWh usable battery , so
(50.8 * (1-(20/100)) = 40.64 KWh used
see how many miles you have gone on the From Last Charge screen. Let us assume X
then X/40.64 will be your miles/KWh

Compare this with what is shown in your From Last Charge screen. I bet they will not be the same. Mine had 11% difference.

Now, hopefully the actual miles you have driven From Last Charge is correct (or we are in big trouble) Also 50.8 usable should be quite accurate since our car are newish (note 1 or 2% degradation is nothing, so let's ignore that). So the only dodgy figure is the % of battery left.

So this is the calculation I hope you will do and post some results. This is for fun and don't get worked up about it. If you drive around 4.1 m/KWh on average you should do 210 miles easy (210/50.8=4.1 m/KWh). In town that is easy until we get to winter again. If you do motorway driving I would say account for (3.7*50.8=187 miles) and you cannot go wrong.

You don't have to charge to 100% of course. If you charge to 80% and drive to 20% then the equation becomes 50.8* (1-((80-20)/100))=30.48 kwh used
If you have a long range version use 61.7 instead of 50.8......Simples


I believe the reason for all discrepancies is that with LFP batteries because the voltage across the cells does not drop much from fully charged to discharged, cars are finding it difficult to guess how much battery you have left. This is why MG and TESLA et all say charge your car to 100% regularly, so the system can reset itself.

Of course the long range version uses NCM so the Cells's voltage drops as it discharges and hence the car knows more exactly how much battery you have left. So if you good sires do this example I think your discrepancies should be less than us with LFP batteries.

This is just for fun so whatever the answer, relax and enjoy this wonderful car. So far nothing can touch this car for fun and value.
 
1685827350421.png
 
I assume this is SR and was charged to 100% then you have a 6% discrepancy. Also, I assume you did a 3h 39m drive in one go (since you are showing FROM START screen and not From Last charge... they are the same until you stop and it resets)
That is not bad. You signature says Driving MG5. Nice to see what the calculations are on those

Also LooLs. You are driving 4.2 m/kwh which is close to 4.1 the car was calibrated against so your car is showing 213 miles range. Nice one.
 
Hi from johnmg5 it's from the MG4 SR I had a MG5 but did not change the username
 
I find my guessometer to be very accurate. The drive stacks up to the distance I have travelled. My daily commute is always the same so that probably gives mine some steady data to work from.

My accumulated total is sitting at 4.1 and that is over about 1700 miles.

I don’t really do air really and use open windows and I drive eco mostly so probably why I sit on the better side of the guessometer.
 
If MG seriously think I can get 4.1 on regular journeys they are in cloud-cuckoo land.
My latest 106 miles from last (100%) charge took me down to 37%, and the GOM showed 3.4 mpkWh. (Car is back on charge)
 
It seems as if using ECO mode and not using the aircon (or the heater - open windows won't warm you up in January) really do make a difference. But a lot of it is down to driving style and the type of roads you usually drive on.

I don't really care. I'm driving that car the way I drove my Golf, except for trying my best to use regenerative braking, not to touch the brakes and not to allow the car to come to a complete stop unless I can't avoid it. I need more practice at that, but I always did see braking as an uneconomical thing to do and tried to position the car to coast round corners if possible.

I so seldom drive more than 70 miles from home that it doesn't bother me. Even next week, a trip to an afternoon tea 65 miles away, is there and back on one charge no problem. The electricity is costing me about half what the petrol cost me, so what the hell. In winter the range might start to be an issue, but the longest regular trip I do in winter is 50 miles to Glasgow, and there are type 2 chargers in the car park I normally use there.

Longer trips, I'm really enjoying that I'm not in a hurry and looking for somewhere nice to spend half an hour or so. Winter, well, we'll see, but I've taken careful note of the rapid chargers around here so I know where I need to stop to top up whichever direction I'm coming from if it looks a bit problematic. If I only need ten miles or so, that's not going to be much longer than filling up with petrol. And there are more chargers around than there are petrol stations.
 
If MG seriously think I can get 4.1 on regular journeys they are in cloud-cuckoo land.
Since the weather has warmed up, I find 4.1 very easy to achieve. I drive in the NORMAL mode but I don't do motorways. Maximum speed would be 40 m/h but usually under 30.

Tell us more about the your driving style (forget A/C etc they make little difference) and what 80% of your driving routes are like.

It seems as if using ECO mode and not using the aircon (or the heater - open windows won't warm you up in January) really do make a difference. But a lot of it is down to driving style and the type of roads you usually drive on.

I don't really care. I'm driving that car the way I drove my Golf, except for trying my best to use regenerative braking, not to touch the brakes and not to allow the car to come to a complete stop unless I can't avoid it. I need more practice at that, but I always did see braking as an uneconomical thing to do and tried to position the car to coast round corners if possible.

I so seldom drive more than 70 miles from home that it doesn't bother me. Even next week, a trip to an afternoon tea 65 miles away, is there and back on one charge no problem. The electricity is costing me about half what the petrol cost me, so what the hell. In winter the range might start to be an issue, but the longest regular trip I do in winter is 50 miles to Glasgow, and there are type 2 chargers in the car park I normally use there.

Longer trips, I'm really enjoying that I'm not in a hurry and looking for somewhere nice to spend half an hour or so. Winter, well, we'll see, but I've taken careful note of the rapid chargers around here so I know where I need to stop to top up whichever direction I'm coming from if it looks a bit problematic. If I only need ten miles or so, that's not going to be much longer than filling up with petrol. And there are more chargers around than there are petrol stations.
Lols. I just saw this and realized ... I just asked you this question
 
Since the weather has warmed up, I find 4.1 very easy to achieve. I drive in the NORMAL mode but I don't do motorways. Maximum speed would be 40 m/h but usually under 30.

Tell us more about the your driving style (forget A/C etc they make little difference) and what 80% of your driving routes are like.

Varies enormously. Twisty A roads, motorway or near-motorway dual carriageways. Yesterday I went into the outskirts of Edinburgh to catch a bus the rest of the way. About 14 miles, 28 miles round trip. Outward journey drops from 760 ft to near sea level, skirting 1000 ft on the way. A road all the way. Return journey reverses that, obviously. I didn't see anything close to 4 on either leg of the journey.
 
Varies enormously. Twisty A roads, motorway or near-motorway dual carriageways. Yesterday I went into the outskirts of Edinburgh to catch a bus the rest of the way. About 14 miles, 28 miles round trip. Outward journey drops from 760 ft to near sea level, skirting 1000 ft on the way. A road all the way. Return journey reverses that, obviously. I didn't see anything close to 4 on either leg of the journey.
Still sounds like you should be getting 4. The car's sweet spot is 40m/h stretches. May be ECO mode would help you as it just slows acceleration, which is the main culprit if you like your speed.
 
Not going to dive into the maths stuff; promised myself to never do that again after school. 😁

That said, I found the GOM of the MG4 to be impressively accurate - adapting to driving style, topography and ambient temperature. Much better than any EV I've driven so far (i3, Model 3, Ioniq 5).
 
If you seriously think I'm going to drive at 40 mph on a 60 mph limit road, you're in fantasy land! I said I don't really care though.

I'm happy to try to maximise regeneration by practising one-pedal driving as much as I can, but show me that road, and I'm off.

1685890208164.png
 
If you seriously think I'm going to drive at 40 mph on a 60 mph limit road, you're in fantasy land! I said I don't really care though.

I'm happy to try to maximise regeneration by practising one-pedal driving as much as I can, but show me that road, and I'm off.

View attachment 18055


Lols. You are miss understanding me.
I said acceleration not speed. ECO mode reduces you acceleration.
Reading between the lines I can now fully understand your m/kwh.
Enjoy your car. Have you named it yet?
 

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