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Hi there,

I'm new to the world of electric cars having only recently bought a five-year VW E-Up, So forgive me if asking an obvious question.

I'm noticing the mileage I have seems to drain more quickly than the distance I am actually travelling. So for example I may do 5 miles but my range has gone from 50 to 40 miles in the same time. Is this normal as the battery gets older, or perhaps it's to do with something else? Any advice much appreciated.

Paul
 

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Hi Paul, welcome. Welcome too to the quirky world of EVs. The range gauge in your car is commonly referred to as the GOM or, guess-o-meter. Accurate range is hard to predict, especially in winter. Your heating will use more energy in cold weather, reducing range. Also you’ll use more energy to begin with as the car heats up. Secondly, the battery stores less energy overall when it’s cold, so will offer lower range than in warmer times of year.

If you can pre-heat your car whilst it’s still plugged in before a journey, you’ll find the range is a little better too

Hope that helps a bit.


Sent from my iPhone using Tapatalk
 

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I don't use the digital range meter as it is only a guess - it doesn't know that , for example, you've got 20 miles ahead all uphill. What I do is always set the trip to zero at the start, when the battery is at 100%, then compare the distance travelled with what's left on the analogue battery meter. So, as the battery meter drops to 7/8, and the distance travelled is 10 miles, then I'm on a good 80 miles. If it's only 9 miles then it's 72. And so on. The 4/8 mark or 50% will give you a pretty good idea of how much further you can go, bearing in mind what the road ahead is looking like. I also find that wind direction and speed will affect range.
 

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If some of those intial miles are uphill your range will drop much quicker than 1:1 but you will get a lot of them back later on in the journey.

At this time of year you can also expect to loose between 3-5 miles range by heating the interior of your car up each time you get in it.
 

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The e-up is fairly range limited im afraid, though driving style (speed, etc) and use of the heater will affect this, as will temperature. A battery at -1 celcius doesnt perform as well as it does at 25 celcius.

One the upside, well done for buying and EV and welcome!
 

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In winter, charging the car just before you need it can help warm the battery, effectively increasing its capacity. If you can heat the car cabin before you leave (on grid power) then that also helps range. Early used Leafs don't have much more useable capacity than your e-up, drivers would commonly use heated seats and steering wheel on the move, instead of the cabin heating!
You could also choose to rapid charge ahead of time if you need more range, as again, this warms the battery, and the battery will take many hours to cool.
Conversely, leaving the car unused for a weekend lets the battery get properly cold, my Ioniq reported battery at 2C this morning. It's up to 7C after a partial charge.
 

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I don't use the digital range meter as it is only a guess - it doesn't know that , for example, you've got 20 miles ahead all uphill. What I do is always set the trip to zero at the start, when the battery is at 100%, then compare the distance travelled with what's left on the analogue battery meter. So, as the battery meter drops to 7/8, and the distance travelled is 10 miles, then I'm on a good 80 miles. If it's only 9 miles then it's 72. And so on. The 4/8 mark or 50% will give you a pretty good idea of how much further you can go, bearing in mind what the road ahead is looking like. I also find that wind direction and speed will affect range.
If you were able to quantify it here, then the car should be able to be programmed to take this all into account. Curious how that GOM calculates its range. But seems to me if I were programming the estimated range left, I'd constantly be updating it based on factors from the 5, 10, 20 minutes of driving. If sat nav is being used I'd want to incoporate elevation data and tap into weather reports for temperature and wind speed/direction. I'd weight that against data I had on previous drives. If I had a fleet of cars ( Tesla ) I'd use data from all those other drives to get a more accurate estimate of how costly a journey was going to be.
I guess there is a lot of scope to get more accurate there, curious how much of this is already being used.
 

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If you were able to quantify it here, then the car should be able to be programmed to take this all into account. Curious how that GOM calculates its range. But seems to me if I were programming the estimated range left, I'd constantly be updating it based on factors from the 5, 10, 20 minutes of driving. If sat nav is being used I'd want to incoporate elevation data and tap into weather reports for temperature and wind speed/direction. I'd weight that against data I had on previous drives. I guess there is a lot of scope to get more accurate there, curious how uch of this is already being used.
More often than not its just the average miles per kwh from the last x miles, multiplied by the kwh left in the battery. Some cars take heater usage out of this calculation and then take off range from the result based on the current heater setting but most just do a simple calculation like that. If you used weather, destination info, etc then you may end up thinking that you can get somewhere because its always really reliable, only for the wind direction to change and the range to suddenly drop. When is the weather accurate anyway? Haha.

Better to have it basic and consistently rubbish in my opinion, everyone knows its rubbish and acts accordingly !

Thanks.
 

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More often than not its just the average miles per kwh from the last x miles, multiplied by the kwh left in the battery. Some cars take heater usage out of this calculation and then take off range from the result based on the current heater setting but most just do a simple calculation like that. If you used weather, destination info, etc then you may end up thinking that you can get somewhere because its always really reliable, only for the wind direction to change and the range to suddenly drop. When is the weather accurate anyway? Haha.

Better to have it basic and consistently rubbish in my opinion, everyone knows its rubbish and acts accordingly !

Thanks.

hehe,

i'd do it as displaying your remaining miles as a safe number along with a hopefull number. Picture a a bar 0 to 100% , a portion of it being green being safe estimate, another 5 to 10 % in blue which is enviromental factors taken into account. This blue area would be more volatile and fluctuate depending on driving style, elevation, weather etc but the green area would be a safe bet.
 

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Until you hop on a motorway for 30 miles at 75.
Better a display that keeps the driver cautious about it's reliability since its almost impossible to make it 100%.
your basically saying might as well not try and make range estimate more accurate because drivers would trust it too much.
It’s a circular conundrum and there is somewhere you are drawing a line and saying “this is plenty ball park enough for me”

All im suggesting is, all of these things should be used to gauge a more accurate range calculation, split coloured bars or no bars, on it’s own , this really doesn’t mean much more then giving you more faith in it. If it ends up wildly different because of external factors then it’s the same situation as we are now, people learn how much faith to put into it and how much to allow for variance.

Also to take into account your example of hopping onto a motorway for 30 miles, in my system that would have been accounted for through the sat nav and with the lack of user input sat nav, machine learning to predict journey based on history.
 

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Most EV GOM readings will have shown a drop in range recently. It's the cold weather that does it.

As to the GOM loosing 10 miles after just five. If those five miles had been downhill the range would likely have gone up instead.
 

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Hi there,

I'm new to the world of electric cars having only recently bought a five-year VW E-Up, So forgive me if asking an obvious question.

I'm noticing the mileage I have seems to drain more quickly than the distance I am actually travelling. So for example I may do 5 miles but my range has gone from 50 to 40 miles in the same time. Is this normal as the battery gets older, or perhaps it's to do with something else? Any advice much appreciated.

Paul
It's just a guess. Best to familarise yourself, over a long time and with experience, with a readout of battery capacity remaining and figure out your own mileage remaining.

But answering your question it should not be anything to do with the battery age unless VW has done something quirky and a bit dumb.
 

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your basically saying might as well not try and make range estimate more accurate because drivers would trust it too much.
I think he's saying best to underestimate than overestimate.

I have a pessimistic Soul (pun) while the Ampera was basically a mind-reader and virtually spot on, always.
 

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Hi there,

I'm new to the world of electric cars having only recently bought a five-year VW E-Up, So forgive me if asking an obvious question.

I'm noticing the mileage I have seems to drain more quickly than the distance I am actually travelling. So for example I may do 5 miles but my range has gone from 50 to 40 miles in the same time. Is this normal as the battery gets older, or perhaps it's to do with something else? Any advice much appreciated.

Paul
I think the discharge curve of the batteries changes as they get older. I had the same thing last week:
I did my first long trip on Tuesday: 42 miles to London & back again in my old Fluence. Driving like Noddy, with no heat, I managed 3.8 on the way there, and 3.3 on the way home drving normally with heat.

Although I preheated, the GOM put the fear of God into me. It initially dropped ten miles in five miles of non motorway driving, and I could see myself running out somewhere with no hard shoulder. Strangely by the time we got into London, the GOM was actually beating my own range estimate.

Actually got there with 23 miles left. I fully charged in London, so put my foot down,and heat on for the trip home. It says I have 21 miles left.
 

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The first few miles in most BEV's are heavy on the battery unless it is at the optimum temperature. Pre-conditioning can help but only so far and especially if you pre-Cond when you are not plugged in.
Just like cold ICE's really.
 

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As an example, yesterday I set off on a completely cold car on a frosty day and my 13 mile commute ate 15 miles of battery.

This morning it warmer but also the car was plugged in and so the cabin was preheated and the battery charging. As a result, 13 miles lightly dined on 9 miles of charge.

The longer you have the car, the more you will be able to interpret the GOM. You'll also likely have a more relaxed attitude to the range showing. I am quite happy tootling off with only 70 miles range of a morning on the basis that I am only ever driving 26 miles under normal circumstances and even if something abnormal occurred, there is a good amount of spare range and the ability to charge out and about if things got desperate, although that really would be off the charts abnormal.
 

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I have a LEAF 40 KWh, the GOM is really inaccurate, but if you are doing the same type and style of driving all the time, I roughly continually work the remaining range out by deducting 10% of whatever the GOM states in Summer. In the Winter I deduct 20% and 15% in spring and autumn, seems to be a reliable way estimating the range using the GOM.
 

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How to drive 5mls and loose 10mls on the GOM ? Easy as.
You arrived home the previous evening in very favourable conditions and acheived 5mls/kwh.and this sets the Calculation for the GOM for the next day.

The next morning its cold and you turn on the heating and drive in unfavourable conditions and you are doing 2.5mls/kwh.

Done it many times.

What you need to trust is that once the heater is up to temp and the batts are up to temp the mls/kwh will normalise. eg At this time of the year with the heater switched on if after doing 2 mls i look at my mls/kwh it has done say 2.5mls/kwh but 15mls later it will be getting up to c4mls/kwh. In summer no heater and warmer batts this will being getting up to 5mls/kwh. One soon learns and for me thats some of the fun.
 
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