Actual wall kw to km rate

[QtownTaxiGreg]

I have done a lot of reading and it all relates to US miles on smooth concrete at high speed.

Most of the time I am lucky to 70kph on pretty smooth bitumen or climbing hills on chipseal at 30 to 40 and getting good regen.

What sort of actual kW out of the wall does it take to do 100km in your world? Less interested in highway miĺage but have at it also.

Cost per kW is all over the map depending on your power plan. Please keep it to kW consumption by your Tesla wall unit.

 

[meloccom]

I’m not sure many EV owners calculate the losses due to charging, as there’s not much you can do about it.
From what I read the most efficient rate of charging is between about 7Kw and 11Kw, the maximum a Model 3 or Y will charge off AC. Lower rates of charging and overheads become a large factor.
DC fast charging will have higher losses as the cars battery needs to be at optimum temperature to charge at the highest rate and it will use power to condition the battery if you navigate to a Supercharger; or it will warm or cool the battery during the charging process if it hasn’t conditioned the battery previously.

 

[QtownTaxiGreg]

If the 11kW charger is on does that mean it pumps 11kW until the battery is full to the programmed level or it that wildly wrong?

I can imagine it ramps up and ramps down for more efficiency.

If you are doing a predeparture timed warm up that comes out in your power bill but not your watts per mile?

 

[meloccom]

Generally any EV won’t ramp down below 11Kw until it’s beyond about 90% state of charge.

 

[QtownTaxiGreg]

Tesla NZ internet bumf says the wall charger is going to be certified for 3rd party billing here.

That is a bit of a turn up for me as no way for any power co to do hourly billings with cheap night rates at my address. If I could have my charger billing me via my power co over my wifi at 50% night rate I would be in clover.

 

[QtownTaxiGreg]

Generally any EV won’t ramp down below 11Kw until it’s beyond about 90% state of charge.

How about ramp up? If that's a nill as well then the maths is simple to compare Tesla claims against real world.

 

[meloccom]

How about ramp up? If that's a nill as well then the maths is simple to compare Tesla claims against real world.

If your Tesla is at a low state of charge and connected to an 11Kw charger it will charge almost immediately at 11Kw from the low state of charge until it starts to taper at above 90%.
You can achieve much higher charge rates of up to 150Kw plus on a public DC quick charger or Tesla Supercharger but it will start to ramp down much earlier.

 

[QtownTaxiGreg]

Good to know, thanks!

 

[QtownTaxiGreg]

What do you make of the 75km added per hour on 11kW charger? Looks like a bit of unlikely bald almost honest reporting to me.

If we accept that then 75/ 11kWh = 6.8 km per kW of wall juice =

0.147kWh per km wall

Convert a commonly achieved US 'watts per mile' 280 aka 0.28kWh per 1.6km =

0.174 kW per km battery

Quid pro quo 84% ballpark charging efficiency for a quick zap.

Still please tell me how our NZ contingent fare on our chipseal at highway speeds.

 

[meloccom]

What do you make of the 75km added per hour on 11kW charger? Looks like a bit of unlikely bald almost honest reporting to me.

If we accept that then 75/ 11kWh = 6.8 km per kW of wall juice =

0.147kWh per km wall

Convert a commonly achieved US 'watts per mile' 280 aka 0.28kWh per 1.6km =

0.174 kW per km battery

Quid pro quo 84% ballpark charging efficiency for a quick zap.

Still please tell me how our NZ contingent fare on our chipseal at highway speeds.

“0.174 kW per km battery”
A Tesla will give you a read out of its efficiency and expresses the above as Watt Hours per Kilometre.
If you’re getting 174wh/K it’s a cold rainy day with lots some uphill sections or your lead footing it somewhat.
I drive a Model S and it’s rated at 181 Wh/km, but I have seen as little as 145 Wh/Km on my regular trip from the NSW Southern Highlands to Sydney as that’s downhill and the return journey is around 250 Wh/Km.
Perhaps someone with a Model 3 and Model Y can give an example of the efficiency they are getting.

 

[QtownTaxiGreg]

“0.174 kW per km battery”
...cold...

Aussie cold is a bit different to kiwi cold. The 147 is derived direct from Tesla NZ claiming the milage gain from an hour of 11kW charging as 75km, so perhaps they are accounting for a lower average ambient temperature? Do they go State by State in Australia?

The 174 is derived from 280 American watts per mile Anerican.

Also, what is your highway surface? Have you experienced NZ style chip seal? How does it compare to yours?

 

[meloccom]

Efficiency ratings are federal, so Australia wide.
I don’t think they simply take USA results and convert them.
IIRC Australia uses Worldwide Light vehicle Testing Procedure (WLTP) and the USA something else.
In the Southern Highlands of NSW it gets to about 0 deg C or just a bit lower in mid winter.
The Hume Highway which is the majority of my trip to Sydney is concrete and bitumen sprinkled with a good dose of potholes.
Last time I was in Auckland we didn’t stray far from the city so haven’t been on NZ Highway for a long time.

 

[QtownTaxiGreg]

Not sure on your bitumen.

'Bitumen concrete', what we call asphalt or asphaltic concrete, is probably similar roughness to actual concrete. Gets put down in 4" lifts of slightly oozy bitumen and stone mix and rolled to compact.

Chip seal is molten bitumen cut back with kerosene to allow it to spray on and then overlayed with greywacke or similar hard angular single grade stone chips to form the running surface. A very cheap way of making a somewhat durable road if you keep the water out of it, which is next to impossible anywhere it rains a bit hard. It is very high rolling resistance compared with bitumen.

 

[QtownTaxiGreg]

0°C is barely even a frost here. Overnight drops to -7 are common but it is usually a few degrees above zero by 10am. Colder up at the ski slopes but don't usually hang about there.

The ski roads are usually good traction for most of the way back down so should get good regen braking.

Cab will live in a nice warm garage and most days not do more than 200km so should be ok with nightly charging I think. Model Y LR.

 

[QtownTaxiGreg]

What's NZ Watts per Km on chipseal when not too cold?

 

[donmac]

0°C is barely even a frost here. Overnight drops to -7 are common but it is usually a few degrees above zero by 10am. Colder up at the ski slopes but don't usually hang about there.

The ski roads are usually good traction for most of the way back down so should get good regen braking.

Cab will live in a nice warm garage and most days not do more than 200km so should be ok with nightly charging I think. Model Y LR.

Earlier, you mentioned the typical speed you drive at. Drag consumes much more energy at higher speeds (it is a velocity cubed factor). The difference in energy consumption between, say, 110 and 115 can actually be seen in the statistics provided by my M3.
(A lot of reported statistics include driving at freeway speeds)
As you are mostly driving town speeds, you will find that how hard you press that pedal will probably make the biggest difference. (It's a nice thrill, but comes at a cost.)
When you have adapted to the Regen braking, your consumption figures will improve a bit, but do expect you will always use noticeably more energy up hill. Drivers have reported "net charging" when descending the Blue Mountains into western Sydney.
Note that the battery chemistry of your vehicle has an impact on what you should regularly charge it to.
Hope the above helps.