EV WLTP figures in the real world

EV WLTP figures in the real world

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CoolC

Original Poster:

4,317 posts

227 months

Monday 20th January
quotequote all
Are there any rule-of-thumb tables to compare WLTP figures to real world use figures?

For example, I have the option of a company car at work, so doing some idle browsing to see what's available, thinking about the 180 mile round trip I do on the days I'm in the office.

If a car is listed as having a WLTP combined figure of 300 miles, that will be the optimal of town driving on a warm day etc.

What would that 300 miles convert to when used on a motorway (the commute to the office is 90% dual carriageway/motorway) in winter, and trying to keep between the optimal 20% and 80% charge?

To Add, We do have a charger at work, but can't always guarantee it will be available, so need to be confident the 180miles is doable on one charge.

Pistonheadsdicoverer

650 posts

59 months

Monday 20th January
quotequote all
Worth checking this site.
https://ev-database.org/uk/

SDK

1,588 posts

266 months

Monday 20th January
quotequote all
In the summer/warmer temps you will achieve, or get close to the WLTP on a single long run, with steady driving
In the Winter 20-40% off the WLTP, depending on use case and driving conditions.

The WLTP of my BMW iX40 is 264 miles.
Twice in August I got over this : 270 and 272, from 100% down to 2% (Mostly motorway, there and back)

In the Winter, 0c or lower, it's about 200 miles.

Edited by SDK on Monday 20th January 16:06

TooLateForAName

4,880 posts

197 months

Monday 20th January
quotequote all
official figures are bks.

Work on an assumption of 3miles/kwh unless one of the big, inefficient things like etron etc in which case allow 2.

JQ

6,307 posts

192 months

Monday 20th January
quotequote all
Pistonheadsdicoverer said:
Worth checking this site.
https://ev-database.org/uk/
The above is all you need, it's based on real world usage, certainly accurate for my car.

Europa Jon

593 posts

136 months

Monday 20th January
quotequote all
EV ranges are very dependent on ambient temperatures, so it's easy to get in an argument. However, I find that the American system is just about realistic for us Brits.

TheRainMaker

6,946 posts

255 months

Monday 20th January
quotequote all
TooLateForAName said:
official figures are bks.

Work on an assumption of 3miles/kwh unless one of the big, inefficient things like etron etc in which case allow 2.
It also depends on the time of year, though.

My i3S can in the summer report 5 mi/kWh using Eco Pro the last few weeks it has been as low as 2.8, now back to 3.

The Polestar on the last 1.8-mile trip did 1.4 mi/kWh with an average on the last charge of 2.19; it is much better in the summer.

Basically you won't really know till you have the car hehe

PetrolHeadInRecovery

251 posts

28 months

Monday 20th January
quotequote all
JQ said:
Pistonheadsdicoverer said:
Worth checking this site.
https://ev-database.org/uk/
The above is all you need, it's based on real world usage, certainly accurate for my car.
Seconded. It is checking the different estimates based on conditions.

In my experience, driving around 80km/h or below, you're closer to the city than the motorway range.

hawkzzter

19 posts

10 months

Monday 20th January
quotequote all
As someone suggested earlier, the ‘cold highway’ range quoted on EVdatabase is the way to go (just bear in mind it’s based on estimated range at -10°c…so is in the depths of a Scottish winter morning).

In terms of a very rough rule of thumb, these cold highway / WLTP ratios are 55-60% - albeit some fall outside (e.g. Polestar 2 LR at 52%, Taycan Plus and EQS450+ above 60%).

If you then multiply by the 20-80% then you’re at 33-36% of WLTP. So if you are thinking say 2 hours between stops at 70mph - that’s 140/0.36 = 390+ WLTP range.

That is really worst case scenario for the UK but you can always relax some of the assumptions as you see fit.


Nomme de Plum

7,050 posts

29 months

Tuesday 21st January
quotequote all
TheRainMaker said:
TooLateForAName said:
official figures are bks.

Work on an assumption of 3miles/kwh unless one of the big, inefficient things like etron etc in which case allow 2.
It also depends on the time of year, though.

My i3S can in the summer report 5 mi/kWh using Eco Pro the last few weeks it has been as low as 2.8, now back to 3.

The Polestar on the last 1.8-mile trip did 1.4 mi/kWh with an average on the last charge of 2.19; it is much better in the summer.

Basically you won't really know till you have the car hehe
This is the most pertinent point

An individual's driving style will have a major impact on range.

Johnson897210

655 posts

6 months

Tuesday 21st January
quotequote all
I just divide by two as a rule of thumb. Official numbers are total nonsense as mentioned.

Nomme de Plum

7,050 posts

29 months

Tuesday 21st January
quotequote all
Johnson897210 said:
I just divide by two as a rule of thumb. Official numbers are total nonsense as mentioned.
I think you have just confirmed my point.

John87

869 posts

171 months

Tuesday 21st January
quotequote all
TheRainMaker said:
It also depends on the time of year, though.

My i3S can in the summer report 5 mi/kWh using Eco Pro the last few weeks it has been as low as 2.8, now back to 3.

The Polestar on the last 1.8-mile trip did 1.4 mi/kWh with an average on the last charge of 2.19; it is much better in the summer.

Basically you won't really know till you have the car hehe
My Polestar 2 with performance pack has managed 2.2mi/kWh over the last 1500 miles so seems about right. In summer I can just about hit 3.

More recent models (and Tesla) will generally do better in terms of efficiency but that's to be expected with the pace of development.

gmaz

4,849 posts

223 months

Tuesday 21st January
quotequote all
Tesla model 3 LR has averaged 4 miles / kWh over the last 12K miles. So the 72kWh battery should be 292 miles. Stated WLTP is 360 so 81%

Simon_GH

689 posts

93 months

Tuesday 21st January
quotequote all
Nomme de Plum said:
Johnson897210 said:
I just divide by two as a rule of thumb. Official numbers are total nonsense as mentioned.
I think you have just confirmed my point.
Worst case scenario is this - sub zero, hilly roads, heating on, sensible margin so no range anxiety etc. My friend has run EVs for years and his Kia will get pretty close to the 320 ‘official’ range in the summer.

Nomme de Plum

7,050 posts

29 months

Tuesday 21st January
quotequote all
Simon_GH said:
Nomme de Plum said:
Johnson897210 said:
I just divide by two as a rule of thumb. Official numbers are total nonsense as mentioned.
I think you have just confirmed my point.
Worst case scenario is this - sub zero, hilly roads, heating on, sensible margin so no range anxiety etc. My friend has run EVs for years and his Kia will get pretty close to the 320 ‘official’ range in the summer.
In the UK I drive a 2020 BMW i3S. I believe WLTP is 173miles. I do trips to LHR T3 every month or so. I do it without charging enroute. It's 144miles return, Mostly A3, M25. Last trip shortly before Christmas showed 6 miles range remaining. Below 10c and I keep to speed limits wherever possible. I use Eco Pro and seat heating but don't like the cabin too warm.

I've driven at near zero but not enough to get any real data.

samoht

6,572 posts

159 months

Tuesday 21st January
quotequote all

See also https://www.pistonheads.com/gassing/topic.asp?h=0&...

re-posting from there Citroen e-C4 range against speed and temperature

the WLTP range corresponds almost exactly to the peak of this graph (a bit over 200 miles)

gmaz

4,849 posts

223 months

Tuesday 21st January
quotequote all
Re efficiency, what surprises me is that a 366kW car like a Tesla 3 LR can have the same efficiency as a 150kW car like a Kona (I've owned both) i.e. about 4m/kWh. It's like a 5 litre V8 having the same MPG as a 2 litre 4 pot.

Nomme de Plum

7,050 posts

29 months

Tuesday 21st January
quotequote all
gmaz said:
Re efficiency, what surprises me is that a 366kW car like a Tesla 3 LR can have the same efficiency as a 150kW car like a Kona (I've owned both) i.e. about 4m/kWh. It's like a 5 litre V8 having the same MPG as a 2 litre 4 pot.
That is due to the high efficiency of an electric motor and the rather dismal efficiency of the ICEs in comparison. The V8 will be relatively less efficient than the 4pot.

SWoll

20,187 posts

271 months

Tuesday 21st January
quotequote all
gmaz said:
Re efficiency, what surprises me is that a 366kW car like a Tesla 3 LR can have the same efficiency as a 150kW car like a Kona (I've owned both) i.e. about 4m/kWh. It's like a 5 litre V8 having the same MPG as a 2 litre 4 pot.
Other factors do play a significant part in that though. We all know aero drag has a massive effect on EV efficiency, and the Model 3 is far superior in that area.