Range Estimate + Route in Nav = Total Inaccuracy

Archimedes

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So, one of the other interesting things about my road trip was how inaccurate the range estimate became once I input a destination into the Nav. Every time I put in a destination and started route guidance, it shaved 15-20% off the range estimate, which I assumed was due to things like elevation change along the route and/or type of road. But it was wrong every time.

In all but one segment, there was zero actual reduction in range, while in one it was a very small actual reduction. I don’t understand why it underestimates so significantly when you input a route. Note, my estimator is very accurate otherwise, as proved by tracking mileages.

The other eye opener was how the fan/AC hammers the range estimate, while range mode has only a very small positive impact.
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philbur

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With the nav it tries to get you to your destination with 20% battery left - not zero - so could that be the diff? are you going by what the car says for total range left? Ive found that what the nav says its spot on - just drove Seattle to Whistler with just one flawless charging stop on the way.

phil.
 

McgR

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With the nav it tries to get you to your destination with 20% battery left - not zero - so could that be the diff? are you going by what the car says for total range left? Ive found that what the nav says its spot on - just drove Seattle to Whistler with just one flawless charging stop on the way.

phil.
For me to. It is amazing how accurate it is. Even when driving in the mountains, summer winter, with or without roofbox it stays accurate. A bit on the conservative, in general after driving 250 km my SoC is 2-3 higher than estimated when I started.

That is, if I stay at the maximal speed. In the Netherlands from 6-19 you can only drive 100 in stead of 130 Km/h it doesn’t take that in account. If my last 100 km are in NL my SoC is higher than predicted when leaving. But is starts to correct the range after driving slower some time.

you can set your desired SoC at arrival in the pcm menu.

I do have P Intelligent Range Manager. I don’t know if that makes a difference for range estimation or only for charge planning.
 

McgR

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So, one of the other interesting things about my road trip was how inaccurate the range estimate became once I input a destination into the Nav. Every time I put in a destination and started route guidance, it shaved 15-20% off the range estimate, which I assumed was due to things like elevation change along the route and/or type of road. But it was wrong every time.

In all but one segment, there was zero actual reduction in range, while in one it was a very small actual reduction. I don’t understand why it underestimates so significantly when you input a route. Note, my estimator is very accurate otherwise, as proved by tracking mileages.

The other eye opener was how the fan/AC hammers the range estimate, while range mode has only a very small positive impact.
Same with me. But it depends on the planned trip. Now I am around 330 km on a full charge. When I enter a long destination with charge stops the range indicator goes to 290-300 km. Which is correct for this time of year.

I did notice that it has difficulties estimating range in down hill drives. I drove down 30 km from 1600 to 1000m. The range started with 300 but was still at 300 when down hill and battery charged dropped from 99 to 96. I think it may not take SoC gained by regen into account.

For driving up hill it was spot on.
 

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I have seen range estimates changing when inputting a destination. But the estimated SoC at destination has been within a few %age points. And that is for doing more that 25k km’s on long trips. Only time it has missed the SoC estimate, was driving through a terrible thunderstorm, where the temperature dropped from 28 C to about 14 C in two minutes and torrential rain. Fully understandable.

Never bothered to look at the estimated km range when planning a longer trip, only interested In SoC at destination and intermediate stops for charging. The Guess-o-meter is not interesting due to elevations etc.
 


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I have seen range estimates changing when inputting a destination. But the estimated SoC at destination has been within a few %age points. And that is for doing more that 25k km’s on long trips. Only time it has missed the SoC estimate, was driving through a terrible thunderstorm, where the temperature dropped from 28 C to about 14 C in two minutes and torrential rain. Fully understandable.

Never bothered to look at the estimated km range when planning a longer trip, only interested In SoC at destination and intermediate stops for charging. The Guess-o-meter is not interesting due to elevations etc.
That is how I navigate too. I look at the SoC on arrival at destination and different charge stops and that was always correct. The range meter it self is less important.
 

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The other eye opener was how the fan/AC hammers the range estimate, while range mode has only a very small positive impact.
During my long wait for the car I spent a bit of time using the range estimator on the Porsche site (which seems to have disappeared now).
The big lesson was that there is a huge range gain going from normal A/C to A/C Eco.
Range mode made so little difference I haven't bothered to use it since it also makes the ride worse.
19" and 20" wheels were about the same but 21" wheels reduce range, very probably width not diameter causing the loss of course.

Overall most predictions were sort of as one would expect, except the huge gain of A/C Eco in most temperatue conditions and modest gain of "range" mode.

I set the A/C to Eco on a long journey in cold temperatures and didn't think the loss of performance was bad - it still starts warming up sooner than an IC engined car - I am leaving it there for the winter since the efficiency for short cold journeys this winter has been dire.
 

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During my long wait for the car I spent a bit of time using the range estimator on the Porsche site (which seems to have disappeared now).
The big lesson was that there is a huge range gain going from normal A/C to A/C Eco.
Range mode made so little difference I haven't bothered to use it since it also makes the ride worse.
19" and 20" wheels were about the same but 21" wheels reduce range, very probably width not diameter causing the loss of course.

Overall most predictions were sort of as one would expect, except the huge gain of A/C Eco in most temperatue conditions and modest gain of "range" mode.

I set the A/C to Eco on a long journey in cold temperatures and didn't think the loss of performance was bad - it still starts warming up sooner than an IC engined car - I am leaving it there for the winter since the efficiency for short cold journeys this winter has been dire.
The range calculator is still up there (on UK site at least).
https://www.porsche.com/uk/models/taycan/taycan-models/taycan/

I have just done the 3 different a/c settings for my RWD PB+ with my typical driving / 20 wheels / 5c

Porsche Taycan Range Estimate + Route in Nav = Total Inaccuracy Screenshot_20230115_090318_Chrome


Porsche Taycan Range Estimate + Route in Nav = Total Inaccuracy Screenshot_20230115_090312_Chrome


Porsche Taycan Range Estimate + Route in Nav = Total Inaccuracy Screenshot_20230115_090306_Chrome
 


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During my long wait for the car I spent a bit of time using the range estimator on the Porsche site (which seems to have disappeared now).
The big lesson was that there is a huge range gain going from normal A/C to A/C Eco.
Range mode made so little difference I haven't bothered to use it since it also makes the ride worse.
19" and 20" wheels were about the same but 21" wheels reduce range, very probably width not diameter causing the loss of course.

Overall most predictions were sort of as one would expect, except the huge gain of A/C Eco in most temperatue conditions and modest gain of "range" mode.

I set the A/C to Eco on a long journey in cold temperatures and didn't think the loss of performance was bad - it still starts warming up sooner than an IC engined car - I am leaving it there for the winter since the efficiency for short cold journeys this winter has been dire.
I think the range estimator on the site is comparing between normal AC and eco plus. Eco plus can only be activated in range mode and does make a big difference in range but also in cooling and heating. With eco setting the range difference IRL is much less.
 

f1eng

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I don’t remember and can’t be bothered to look for it again on the site - if it still exists.
I haven’t done a rigorous scientific test but the miles per kWh in the My Porsche report are consistently better since I went to A/C Eco.
I have left it there.

I think the range estimator on the site is comparing between normal AC and eco plus. Eco plus can only be activated in range mode and does make a big difference in range but also in cooling and heating. With eco setting the range difference IRL is much less.
 
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Archimedes

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Follow up to my post. I assume that it was adjusting for things like temp, grade, type of road etc, which would be fine. But it was getting it wrong every time. It was assuming degradation where there wasn’t any.

Also it wasn’t an issue of remaining charge, as it was getting that wrong too. Let’s say my range was 220 miles and the trip was 165 miles, so 25% SOC should be left. I put in the route and it immediately says range of 180 miles and est SOC at destination of say 10%. But then as I travel both go up and I arrive with 55 miles and 25% SOC left.

It was annoying because even though I knew it was wrong, I couldn’t stop clock watching to make sure I made it with room to spare. I was beginning to think that maybe it was a legal thing, where Porsche just decided that it would always leave an x% buffer on any route placed in the Nav, so they could never get sued if someone failed to reach their destination and something bad happened.

Oh and I was in range mode the whole time, most of it with air off entirely.
 
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Scandinavian

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Follow up to my post. I assume that it was adjusting for things like temp, grade, type of road etc, which would be fine. But it was getting it wrong every time. It was assuming degradation where there wasn’t any.

Also it wasn’t an issue of remaining charge, as it was getting that wrong too. Let’s say my range was 220 miles and the trip was 165 miles, so 25% SOC should be left. I put in the route and it immediately says range of 180 miles and est SOC at destination of say 10%. But then as I travel both go up and I arrive with 55 miles and 25% SOC left.

It was annoying because even though I knew it was wrong, I couldn’t stop clock watching to make sure I made it with room to spare.

Oh and I was in range mode the whole time, most of it with air off entirely.
That is not at all my experience? If I start in normal mode I get very accurate SoC at destination. If I switch to Range mode ( very unlikely since the difference is minimal) it adjusts and gets accurate then as well?

Strange
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