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Discussion Starter · #1 ·
I thought this chat was interesting, so sharing with the good people of this forum. It's between Polestar CEO, Thomas Ingenlath and TU, a Norwegian media company covering all kinds of technology. After the first 40 seconds of bjørk bjørk, the actual chat is all in English.

Key takeaways for me:
  1. It is possible to improve start-up efficiency of Polestar 2 (and make other deep changes) using software updates.
  2. Polestar will launch a 'non-conventional' looking SUV in the next few years.
  3. Precept will be a low volume car (like Polestar 1?)

Edit: the video is from today, not from 01.01.1970 as the article might suggest! 🤷🏼‍♂️
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Discussion Starter · #3 ·
That Precept spy-shot looks promising!

edit: I'm happy to hear Scandinavians understand that Americans have been trained to hear Swedish as "bjork bjork" from the muppets
The first 40ish seconds are in Norwegian, but I didn't expect most people here to tell the difference, so used the Swedish imitation from the muppets anyway! 😁
 

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Key takeaways for me:
  1. It is possible to improve start-up efficiency of Polestar 2 (and make other deep changes) using software updates.
It seems to me that in dual motor BEV efficiency could easily be increased by running only a single motor at speed. Watching Tesla Bjorn videos, I've noticed that the dual motor Teslas frequently only power one of the motors at highway speeds, much like an ICE engine deactivating cylinders on the motorway once they've attained speed. Does the Polestar do this? That seems an easy software fix that might instantly and, perhaps, meaningfully increase efficiency and range.
 

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Discussion Starter · #5 ·
Nope. You need a different kind of motor (asynchronous) to be able to turn it off and free-wheel it. There are lots of considerations to account for when choosing the motor type in a vehicle, and Polestar has gone for identical synchronous motors on both axles.
 

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Nope. You need a different kind of motor (asynchronous) to be able to turn it off and free-wheel it. There are lots of considerations to account for when choosing the motor type in a vehicle, and Polestar has gone for identical synchronous motors on both axles.
So variables impacting efficiency include:
1) weight of vehicle (mostly fixed)
2) speed of travel (driver dependent)
3) temperature (fixed, but variable)
4) intrinsic motor efficiency (variable and software dependent?)

Battery capacity is software dependent, but shouldn't impact efficiency, only range.

So how exactly does Polestar plan to increase efficiency of the identical synchronous motors via software update?
 

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So variables impacting efficiency include:
1) weight of vehicle (mostly fixed)
2) speed of travel (driver dependent)
3) temperature (fixed, but variable)
4) intrinsic motor efficiency (variable and software dependent?)

Battery capacity is software dependent, but shouldn't impact efficiency, only range.

So how exactly does Polestar plan to increase efficiency of the identical synchronous motors via software update?
The biggest thing that's a consumption suck right now, from what I've seen, is how it uses/enables cabin and battery heating, and possibly how it uses and applies friction brakes or not in city/suburban driving. And those things could definitely get better with software tweaks because I think they've made assumptions around what's needed that're probably inaccurate or could be tuned differently if we're optimizing for range/efficiency instead of performance.

I just did an experiment. Did an ~8 mi trip at similar ambient temperature (~10C/50F) but over different roads:
Trip 1 was over surface suburban roads, lots of traffic lights, 30s mph and stop/go generally, up to 50 mph on an expressway. Consumption >45 kWh/100 mi
Trip 2 used a highway for the most part (~6.5-7 mi out of 8), 60-80 mph for the highway parts, 20-40 mph stop/go for the rest. Consumption 38 kWh/100 mi


Factors 1,3,4 were all the same. Factor 2 (speed) should've made Trip 2 worse than Trip 1.
The main things I think that made Trip 2 less battery consuming than Trip 1 was that I effectively yo-yo'd the battery usage and generated battery heating that way just from the nature of driving on a busy highway for a few miles. And, I came to a stop less for trip 2 than trip 1.

In Trip 2, when it was early in the trip, After one highway stretch I could see the consumption drop from 50s to low 40s, and then at a light waiting for the next highway on ramp, I could see the consumption creep up slowly from 42.5 to 44 while just sitting idle at a light. This is presumably the car using the heater to get to some optimal temperature.

I think how they program the car to handle stop/go traffic (which could be done using map/nav data?) and how they use the battery heater (and enable preconditioning while charging) will be the best ways they can OTA improve consumption.
 

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The biggest thing that's a consumption suck right now, from what I've seen, is how it uses/enables cabin and battery heating, and possibly how it uses and applies friction brakes or not in city/suburban driving. And those things could definitely get better with software tweaks because I think they've made assumptions around what's needed that're probably inaccurate or could be tuned differently if we're optimizing for range/efficiency instead of performance.

I just did an experiment. Did an ~8 mi trip at similar ambient temperature (~10C/50F) but over different roads:
Trip 1 was over surface suburban roads, lots of traffic lights, 30s mph and stop/go generally, up to 50 mph on an expressway. Consumption >45 kWh/100 mi
Trip 2 used a highway for the most part (~6.5-7 mi out of 8), 60-80 mph for the highway parts, 20-40 mph stop/go for the rest. Consumption 38 kWh/100 mi


Factors 1,3,4 were all the same. Factor 2 (speed) should've made Trip 2 worse than Trip 1.
The main things I think that made Trip 2 less battery consuming than Trip 1 was that I effectively yo-yo'd the battery usage and generated battery heating that way just from the nature of driving on a busy highway for a few miles. And, I came to a stop less for trip 2 than trip 1.

In Trip 2, when it was early in the trip, After one highway stretch I could see the consumption drop from 50s to low 40s, and then at a light waiting for the next highway on ramp, I could see the consumption creep up slowly from 42.5 to 44 while just sitting idle at a light. This is presumably the car using the heater to get to some optimal temperature.

I think how they program the car to handle stop/go traffic (which could be done using map/nav data?) and how they use the battery heater (and enable preconditioning while charging) will be the best ways they can OTA improve consumption.
Thanks for the insight. I'm genuinely interested in this question. I'm new to EVs, other than my wife's PHEV BMW X5 40e, which doesn't really count. I had always assumed that since the mechanical bits were fixed that range/performance were as well. What I've learned, however, is that with regard to range manufacturers can increase usable battery capacity by reducing top/bottom buffers, and they can alter charging curves through software tweaks of the BMS. I hadn't really considered that software could alter more than that, but I guess it makes sense.

From what I can tell, regeneration is a relatively minor factor impacting consumption compared to the others I listed above. I'm basing this on several videos I've seen indicating similar consumption numbers between one pedal driving and standard driving in the PS2. I wonder how much difference braking/regen can really make. I don't have my PS2 yet, so I'm just basing this on what I've seen on YouTube.

With regard to temperature, I live in the Southern US, so I think I'm fortunate in that it rarely gets below 40 degrees F (4.5C), and certainly in summer we'll have no problem keeping the battery warm (quite the opposite, in fact). I wonder how different the consumption will be in the summer compared to the winter, as all the testing I've seen of the car has been in the colder months in late 2020, and mostly in Norway and other Scandinavian countries. Can we expect 25% more range when it's warm? Does anybody know?

I think the biggest issue with the PS2's consumption is its weight. It weighs at least 600 pounds more than the heaviest Tesla Model 3. It's a lot of extra heft to haul around.
 

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Excuse me veteran forum dwellers as I repeat myself here, but the biggest difference in efficiency between the Polestar 2 and the Teslas is the higher drag coefficient multiplied by the greater frontal area. The weight difference effect is minor in comparison.

The higher drag coefficient is largely a result of the styling, including the unnecessary but attractive grill. I'm happy to sacrifice some range for a car I love the looks of.
 

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Excuse me veteran forum dwellers as I repeat myself here, but the biggest difference in efficiency between the Polestar 2 and the Teslas is the higher drag coefficient multiplied by the greater frontal area. The weight difference effect is minor in comparison.

The higher drag coefficient is largely a result of the styling, including the unnecessary but attractive grill. I'm happy to sacrifice some range for a car I love the looks of.
Agree with you on styling 100%.

A quick check of some drag coefficients (Cd):
TM3 - 0.23
PS2 - 0.278
eTron - 0.28
iPace - 0.29
Kia eNiro - 0.30

Obviously the Kia is in a different class (single motor, etc) but is supposed to be a very efficient vehicle despite its high Cd.

Too many variables to consider. Let's just enjoy the looks (and soon the drive :)) of the PS2! December 29th can't come soon enough!
 

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Excuse me veteran forum dwellers as I repeat myself here, but the biggest difference in efficiency between the Polestar 2 and the Teslas is the higher drag coefficient multiplied by the greater frontal area. The weight difference effect is minor in comparison.
Once they release the software update that offers the option of reducing drag or reducing weight we’ll compare and know for sure.
 

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Drag coefficients matter more the faster you go, around town doing 30mph it will make little difference, so only comes into effect at constant Motorway Speeds. The E-Niro does well as it's only RWD. The I-Pace is around the same as the Polestar. The difference between 0.23 and 0.28 doesn't sound a lot, but at 70mph it's massive.

Weight plays a small part. Go to ABRP ... add a ton to Model 3 and the range is hardly impacted - Same with any EV. It does play a slighter bigger part driving around town more than motorway range ... but again it's minimal.

Both these are factors but not the some of the bigger Polestar Issues. As others have mentioned it's the identical synchronous motors are one area of issue. This is the same as the I-Pace. I'm sure it's got some pro's over the asynchronous motors, but efficiency isn't one of them.

The I-Pace is the closest car to the Polestar - it weighs nearly the same, it has the same drag and motors. The I-Pace has a 90kWh battery and gets similar efficiency.


None of the above will change with a software update - if they can help, it will only be a few % at best.


Finally, I've tested this to death now ... it's the heating of the batteries that's causing massive early loses, especially in winter.

This is where they could improve range:-
  • An ECO mode where it restricts power/performance and where the heating of the batteries isn't prioritised. This would be ideal for short stops ... as by the time the car gets the batteries up to temp you've probably stopped - hence why we are seeing 56kWh/100mi in winter ... it's heating the car and batteries. Yes you can manually use heated seats/wheels to help, but the car still wants to get those batteries warm ASAP.
  • Pre-Heating the Batteries while plugged in, along with the cabin pre-heating - Why this isn't a standard feature now is beyond me ... hopefully this will be OTA soon!
  • While I'm here, let us to pre-heat the batteries manually if we know we are going to charge soon, or do like the Tesla's and if a charger is the destination do it automatically - won't help range but will help max charging speeds.
The main problem is now, that with most trips (in the UK) being less than 100miles ... and due to Covid, most really being 10-20mi at most ... at 50+ kWh/100mi for each trip you are getting at best 140mi ... then add the fact that you'll only charge to 80/90% and go down to 20%, a lot of people are doing a couple of trips, less than 80miles and need to charge from 20 to 90% again.

People doing 120+ miles don't seem to have a problem, as once the car is warm the efficiency drops well below 30kWh, but due to the ridiculous start up draw, the average seems to settle around 35ish.

How they fix this I don't know ... I'm not sure what they can or can't do. But next winter if people are not getting 150+ miles from 10 x 15mi trips then people are not going to have confidence in the brand name, which will hurt them long term.
 

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Drag coefficients matter more the faster you go, around town doing 30mph it will make little difference, so only comes into effect at constant Motorway Speeds. The E-Niro does well as it's only RWD. The I-Pace is around the same as the Polestar. The difference between 0.23 and 0.28 doesn't sound a lot, but at 70mph it's massive.

Weight plays a small part. Go to ABRP ... add a ton to Model 3 and the range is hardly impacted - Same with any EV. It does play a slighter bigger part driving around town more than motorway range ... but again it's minimal.

Both these are factors but not the some of the bigger Polestar Issues. As others have mentioned it's the identical synchronous motors are one area of issue. This is the same as the I-Pace. I'm sure it's got some pro's over the asynchronous motors, but efficiency isn't one of them.

The I-Pace is the closest car to the Polestar - it weighs nearly the same, it has the same drag and motors. The I-Pace has a 90kWh battery and gets similar efficiency.


None of the above will change with a software update - if they can help, it will only be a few % at best.


Finally, I've tested this to death now ... it's the heating of the batteries that's causing massive early loses, especially in winter.

This is where they could improve range:-
  • An ECO mode where it restricts power/performance and where the heating of the batteries isn't prioritised. This would be ideal for short stops ... as by the time the car gets the batteries up to temp you've probably stopped - hence why we are seeing 56kWh/100mi in winter ... it's heating the car and batteries. Yes you can manually use heated seats/wheels to help, but the car still wants to get those batteries warm ASAP.
  • Pre-Heating the Batteries while plugged in, along with the cabin pre-heating - Why this isn't a standard feature now is beyond me ... hopefully this will be OTA soon!
  • While I'm here, let us to pre-heat the batteries manually if we know we are going to charge soon, or do like the Tesla's and if a charger is the destination do it automatically - won't help range but will help max charging speeds.
The main problem is now, that with most trips (in the UK) being less than 100miles ... and due to Covid, most really being 10-20mi at most ... at 50+ kWh/100mi for each trip you are getting at best 140mi ... then add the fact that you'll only charge to 80/90% and go down to 20%, a lot of people are doing a couple of trips, less than 80miles and need to charge from 20 to 90% again.

People doing 120+ miles don't seem to have a problem, as once the car is warm the efficiency drops well below 30kWh, but due to the ridiculous start up draw, the average seems to settle around 35ish.

How they fix this I don't know ... I'm not sure what they can or can't do. But next winter if people are not getting 150+ miles from 10 x 15mi trips then people are not going to have confidence in the brand name, which will hurt them long term.
Average car journey length in the UK is 8.4 miles.
 

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Average car journey length in the UK is 8.4 miles.
Yes the average is 8.4mi ... but 99.99% are less than 100mi.

Assuming 9 miles per trip, I'd expect being able to do 16+ 9mi Trips from a 90% charge to 10%. At present some people are getting around 6+ ... ok it's cold ... but still 1/3 of the range from 2/3rds of the WLTP range is very poor.
 
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Yes the average is 8.4mi ... but 99.99% are less than 100mi.

Assuming 9 miles per trip, I'd expect being able to do 16+ 9mi Trips from a 90% charge to 10%. At present some people are getting around 6+ ... ok it's cold ... but still 1/3 of the range from 2/3rds of the WLTP range is very poor.
Last night I drove home from work (10 miles)
1 hour later went to play tennis (9)
2 hours later back home (9)
Into work this morning (10)
My journeys are very average, not flat but not hilly at all.
Charge went from 89% to 63% so 26% for 38 miles.
My range for 90% to 10% of battery is 117 miles based on my average usage. Not been an issue yet. It's a good job I love every other aspect of the car!
 

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Yes the average is 8.4mi ... but 99.99% are less than 100mi.

Assuming 9 miles per trip, I'd expect being able to do 16+ 9mi Trips from a 90% charge to 10%. At present some people are getting around 6+ ... ok it's cold ... but still 1/3 of the range from 2/3rds of the WLTP range is very poor.
Yup, my trips to town & back are 12 miles (with a stop of 30-40 minutes while I do my shopping) which uses 11% of the battery. The range here isn't a problem...but the efficiency/cost per mile is actually worse than an ICE car.
 

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Yup, my trips to town & back are 12 miles (with a stop of 30-40 minutes while I do my shopping) which uses 11% of the battery. The range here isn't a problem...but the efficiency/cost per mile is actually worse than an ICE car.
Depends on the car and price per kWh.

Let's say it's 1% of battery per Mile. 1% of 70kW = 0.7 (or 70 miles range)

0.7 x 15p per kWh then that's 10.5p (if you have an off-peak supply that's 5p pkWh that's 3.5p per mile)

25mpg Car = 21p
30mpg Car = 17.5p
35mpg Car = 15p
40mpg Car = 12.5p
45mpg Car = 10p

So you would need to be paying 15p per kWh and had a 45mpg car for it to be roughly the same.

However a lot of other health benefits over Diesel ICE.
 
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So you would need to be paying 15p per kWh and had a 45mpg car for it to be roughly the same.
42mpg in my previous car (1.5l Petrol VW Golf) and yes, was paying 15p/kWh (but moving onto Octopus Go). I don't think that special EV tariffs should come into it - EVs were supposed to be cheaper (<5p per mile) without special tariffs which are priced attractively to encourage overnight charging habits and Polestar's own website uses 19p/kWh.

Even Pod-Point reckon the P2 should cost 4.18p/mile so it's costing over twice as much?

A big factor in my decision to buy an EV was a cheaper cost per mile but at the moment because the car's efficiency for shorter journeys is pretty bad I'm not seeing it. As mentioned earlier in the thread, if they can better balance the heating of the battery (e.g. over a longer time) I think that would help.
 
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Regarding causes for range loss :

The Mach-e estimated range has been published.
I think it's the first time we get ranges for both (true) 4WD and RWD versions of a same car.

It turns out that for both battery packs (68 and 88kWh), the 4WD has a 10% range loss.
My guess is that the future two-wheel drive version of the Polestar 2 will have a 10% range increase too.
 

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I mean no ill will, nor do I want to be snarky in any way, but spending this amount of money on a car to save some money on fuel strikes me as silly. Buy it for a hundred good reasons including style, uniqueness, philosophy, design approach, cleaning the air, reducing noise pollution, and saving the planet, yes! But the amount of money you'll save on fuel over the lifetime of the car? No.... I don't think that amounts to much, really. There are far more economical BEVs out there for that, no?

Really... I sincerely don't wish to be critical or to offend.
 
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