EV general discussion

[Joe T]

The Polestar website has a calculator which shows the impact of the following variables on the P2 range:

• Driving : Motorway is worst, city is best. There is a 62 mile impact from all motorway to all city.
• Temperature : Going from 25c down to 5c reduces range by 20 miles
• Air Conditioning : Having this on reduces range by 6 miles
• Wheel Size : Selecting 20" wheel over the standard 19" reduces range by 25miles

Setting all of the options to worse case* reduces the range by 106 miles [From 292 miles to 186 miles]
* Highway, -15c, AC on and 20" wheels

Interesting

Agreed, it's fascinating isnt it. Some of it is counter-intuitive to drivers used to driving ICE cars, especially the first point.

 

[[TW]Fox]

Driving : Motorway is worst, city is best. There is a 62 mile impact from all motorway to all city.

This has potentially quite big ramifications for the use of EV for proper journeys. What is the technical reason for this as it's the opposite to what you get with ICE?

I don't mind admitting my scepticism of EV is because I cannot see how it will do anything but materially impact me for my preferred vehicle usage. We like to use the car to cover significant distances. For local use I'm already sold on the concept, if it wasn't for the fact I want to try and get maximum value out of the car we bought new 3 years ago I would absolutely have an electric Mini right now.

But we think nothing of using the car to cover hundreds of miles in a single day and large tank range is something that's very important. This is atypical usage sure but if you're going to ban something its reasonable to ensure that people's needs are properly met by the alternative.

My idea of the ideal driveway is an EV for local running and a long range ICE for long journeys. This results in much lower local emissions whilst retaining the flexibility a conventional car offers. But this ban will preclude this.

 

[Joe T]

This has potentially quite big ramifications for the use of EV for proper journeys. What is the technical reason for this as it's the opposite to what you get with ICE?

You've presumably heard of battery regeneration (useful in city driving) and aerodynamics (affecting high speed driving)?

 

[Jonnycoupe]

Linear efficiency in an EV. And ICE isn’t. At higher load and more rpm the thermal efficiency and extraction of energy from the fuel increases which counters the increased road load, compounded by no/limited regen.

Aero resistance increases at square of speed so an EV is closer to the logic of physics where double the speed needs quadruple the energy - of course we don’t see that jump in consumption as you are covering more distance in that time.

 

[SDK^]

Linear efficiency in an EV. And ICE isn’t. At higher load and more rpm the thermal efficiency and extraction of energy from the fuel increases which counters the increased road load, compounded by no/limited regen.

Aero resistance increases at square of speed so an EV is closer to the logic of physics where double the speed needs quadruple the energy - of course we don’t see that jump in consumption as you are covering more distance in that time.

That's exactly the answer I was going to post

 

[[TW]Fox]

So rather than say 'EV's are less efficient on the Motorway' its probably fairer for us to say 'EV's are even more efficient in town'.

ie, an ICE is particularly crap in town but good on the Motorway, but an EV is particularly good in town and good on the motorway?

Of course this still does then raise the issue that even those cars claiming a usable range of 250-300 miles probably won't do that in one hit - only consecutively around town. Where range is actually far less of an issue (a car with a range of only 100 miles would work perfectly for virtually all the usage our Mini gets, whereas I routinely find the 500+ mile tank range of my 530d or similar cars very useful).

I really would like to point out that i am *not* anti EV, I am simply worried that an EV would be a step down in usability from the cars I prefer to drive.

If BMW released a 5 Series tomorrow with a usable 500 mile electric range on the motorway I would immediately trade my 530d in and never look back. I have no particular fondness for diesel, I just cannot see anything else on the market that can do what it does.

 

[jpaul]

...with correction that
aerodynamic impact is V^3, and range loss on motorway of an ICE, at 75 vs 56 mph, will be similar to EV.

 

[Kenai]

So rather than say 'EV's are less efficient on the Motorway' its probably fairer for us to say 'EV's are even more efficient in town'.

ie, an ICE is particularly crap in town but good on the Motorway, but an EV is particularly good in town and good on the motorway?

Of course this still does then raise the issue that even those cars claiming a usable range of 250-300 miles probably won't do that in one hit - only consecutively around town. Where range is actually far less of an issue (a car with a range of only 100 miles would work perfectly for virtually all the usage our Mini gets, whereas I routinely find the 500+ mile tank range of my 530d or similar cars very useful).

I really would like to point out that i am *not* anti EV, I am simply worried that an EV would be a step down in usability from the cars I prefer to drive.

If BMW released a 5 Series tomorrow with a usable 500 mile electric range on the motorway I would immediately trade my 530d in and never look back. I have no particular fondness for diesel, I just cannot see anything else on the market that can do what it does.

For most people like you, PHEV will be the preferred solution for a while after the pure ICE ban I think - typically 30 to 40 mile EV range that will give great cost savings for local driving but with the flexibility to not worry about range on longer trips. Something like the 530e or 545e would presumably suit you well?

 

[Joe T]

I really would like to point out that i am *not* anti EV, I am simply worried that an EV would be a step down in usability from the cars I prefer to drive.

The problem is that you want all of the advantages without ANY (even minor) disadvantages. A Tesla Model 3/S would probably do what you want, with the small proviso with having to take slightly longer breaks on your 500 mile journeys which I imagine you do less than 10 times a year?

 

[[TW]Fox]

I agree and for a time was almost convinced I'd buy a 545e next. However I'm still not sure I am sold on the G30 LCI. I rented one (LCI, not 545e) for a couple of weeks a few months ago and it was a fantastic car but I can't help thinking they've spoiled the styling with the Passat front lights and awful selection of standard fit black wheels.

I think I've narrowed my choice down to either M340i or 545e M Sport. A shame that the 545e has both the smaller battery from a 530e and the smaller fuel tank, so doesn't offer the sort of touring range a 540i does (and certainly not that a 530d does).

 

[[TW]Fox]

The problem is that you want all of the advantages without ANY (even minor) disadvantages.

I want to lose nothing I already have. I'm not sure this is unreasonable as I can currently go out and buy numerous cars that offer exactly what I have now and do the job perfectly. But will be illegal to buy in under 10 years.

I accept that my usage is atypical, but at the end of the day we buy cars to do what we want them to not what would be useful for others to do with them.

I never drive distances like that non-stop but it's rare that I make stops where there are ample charging units around that will replenish all the range I need in 20 minutes without having to wait around for them to become free. Probably my most common long trip (Well, before the current situation!) was home to airport to home. You cannot rely on being able to plug in at the airport parking and my current car will do home to the airport, park and return back home on a single tank of fuel. Part of this is my fault for choosing to live so far away but like I said, my current car does exactly what I want..

A Tesla Model 3/S would probably do what you want, with the small proviso with having to take slightly longer breaks on your 500 mile journeys which I imagine you do less than 10 times a year?

The Model 3 almost has the technical ability but isn't the package a 5 Series is. I remain frustrated that BMW still don't offer anything like it and every time they do come out with a full EV it looks like a bizarre concept car. Last weeks ridiculous iX whatever is a case in point. Just make a normal car that is electric for goodness sake!

 

[Joe T]

I want to lose nothing I already have. I'm not sure this is unreasonable

Your posts about car buying have always come from a rational perspective (i.e. ignoring any human element), but I see this has changed (maybe as you got older?). It seems stubborn-ness and a dislike of change has taken over.

A rational perspective would be - am I better or worse off on a net basis by moving to an EV?

 

[Jonnycoupe]

3 series and i4 aren’t far away, any compromise to the rear passengers that EV might bring won’t bother you anyway, as opposed to the SUV offerings that give comfort in 4 seats.

You will gain significant drivability and refinement - you will enjoy that every single journey. Not these long journeys where most people hit peak bladder first. Horses for courses I guess... although they are definitely just for leisure activities now.

 

[[TW]Fox]

I'd be happy with a full EV current model 3 series too.

I don't mind compromise, my current car is a compromise as I am not a particular diesel fan.

 

[Journey]

Interesting to see it's still 2020, but Tesla just opened a charging station with 56 250kW v3 chargers. What will they achieve here in the next 10 years, if this is where they are at now.?

 

[McPhee]

In terms of time, I think 2030 is a decent target year. With this parliamentary term ending in May 2024, doing nothing isn't really an option if the target is to be met (unlike, say, a 2035 or 2040 target).

Though personally, I'm not keen on a ban. I'd prefer to see increasingly punitive taxes levied against the sale of ICE cars. Let people drive them if they wish, but they'll pay for the privilege, and the proceeds can then be reinvested in green projects. If those projects offset more carbon emissions than the car generates, then everyone wins. At some point, ICE cars will become specialist vehicles anyway, as manufacturing moves to BEV and HFCV, service centers lose the expertise required to work on ICE vehicles, etc.

 

[Neil777]

In terms of time, I think 2030 is a decent target year. With this parliamentary term ending in May 2024, doing nothing isn't really an option if the target is to be met (unlike, say, a 2035 or 2040 target).

Though personally, I'm not keen on a ban. I'd prefer to see increasingly punitive taxes levied against the sale of ICE cars. Let people drive them if they wish, but they'll pay for the privilege, and the proceeds can then be reinvested in green projects. If those projects offset more carbon emissions than the car generates, then everyone wins. At some point, ICE cars will become specialist vehicles anyway, as manufacturing moves to BEV and HFCV, service centers lose the expertise required to work on ICE vehicles, etc.

It's ok saying offsetting carbon emissions but that doesn't address the street level health effects of emissions.

 

[[TW]Fox]

It's ok saying offsetting carbon emissions but that doesn't address the street level health effects of emissions.

Street level emissions are easily solved with PHEV. I don't really understand why PHEV diesel isn't more of a thing - low co2 and high range for long journeys and zero emissions within the city. You could even legislate to mandate zero emissions running within city boundaries once take-up was high enough.

 

[McPhee]

It's ok saying offsetting carbon emissions but that doesn't address the street level health effects of emissions.

True. But then BEVs shift this problem anyway, as opposed to eliminating it. Particulates from exhaust fumes would fall, but particulates from tyre wear would rise, owing to the higher weight of a typical passenger car. I'm not sure what the net effect is without looking it up (it's not just the overall amounts of particulate matter that are important, but the size and composition of that matter), but it's a known problem regarding the EV transition and particulates.

 

[Fusion]

Aero resistance increases at square of speed so an EV is closer to the logic of physics where double the speed needs quadruple the energy - of course we don’t see that jump in consumption as you are covering more distance in that time.

It’s even worse than that- eight times! (Power is proportional to change in speed cubed). But, yeah- what you said.