500Wh/mile normal for short trips?

[rotor2k]

Morning all,

I just want to confirm that my numbers are ok -- they seem extremely high. Yesterday I went somewhere and then came back, ~15 miles in total, around 90 minutes driving (south London, so slow going). Average speed something like 10mph, maximum speed 30mph. When I set off I had 80% battery, and when I returned home I had 66%, and by the evening that had dropped to 62% (I think conditioning?). Temperatures throughout the day were 5-6 C.

So a drop from 80% to 66% for 15 miles, a further loss of 4% to (possibly) conditioning. The overnight charge to bring it back to 80% took 2h04.

It seems excessive that it needs 2h of charging at 32A to give me 15 miles of 10mph driving. Is this normal? And what was going on with the conditioning? Is the car thinking it needs to warm up further (even when I got back I still didn't have full regen).

 

[mj88]

Doesn't sound dissimilar to my S if I don't preheat, saw it peak at 800 last week on a very cold morning for an emergency 5 miles school run.

 

[RickW]

I'm no battery expert but I think that the numbers that you have given, especially with the slow speeds, may reflect heating the cabin among other things.

See if you have all 3 fans on when you turn the heater on (also reduce fan speed to 3 or below) and also set your temperature to 70 degrees (Fahrenheit); use the seat heater as much as possible, as opposed to the fan. I find that if I use just one fan and not all 3, the WH/Mi goes down. Another energy stealer is the TeslaCam both in Sentry mode and in mobile mode. I trust that you are also in Chill mode. I've been experimenting with this as well and the things listed above have been the main battery drain for me.

 

[Adopado]

Short journey's can sometimes show numbers like that. However, don't extrapolate that to assume that your overall range for a lengthy journey will take anything like the same kind of hit.

 

[rotor2k]

Thank you all for your input. I look forward to the summer when these “it’s cold” problems go away.

 

[Adopado]

I trust that you are also in Chill mode.

Being in Chill Mode will not of itself make a difference to range. If a driver tends to be a bit heavy footed and has not developed a smooth and progressive use of the accelerator in Standard mode then being in Chill could help a bit but not otherwise. If you do end up driving more slowly overall then yes, Chill should give some range benefit... but you can do the same in Standard mode just by moderating speed and being more progressive with the pedal.

 

[DJP31]

Thank you all for your input. I look forward to the summer when these “it’s cold” problems go away.

Absolutely! The winter is a killer for kW/m and if you extrapolated the short journey energy costs you’d never trust the car to go more than 100 miles. The reality is there is a huge ‘departure tax’ during the winter, my consumption for my 4 mile commute virtually doubles, but I couldn’t care less as as my fuel station is on my drive. I charge overnight on Economy 7 so whether it takes one hour or two doesn’t matter - I’m asleep.

Over the last two winters on long journeys winter consumption is about 20% higher, so still noticeable but nowhere near as bad as the short journey would suggest it might be.

 

[wcorey]

Given the temperature, biggest contributor is heater. It would also be affected by your driving style. If you are one to 'punch it', that'll effect wh/mile as well. Sure, you could use 'chill mode' but the better approach is to moderate your driving style. Be conscious of acceleration/deacceleration cycling. In other words oscillating around a given speed, say 40, going from 42 to 38 to 42, etc. Those, obviously, are identical to things that would happen in a gas driven car but it's like going from a std 27 mgp car to a Prius. The new Prius owner is told to feather and hypermiling. Those same techniques work with a Tesla as well. You'll find some critical of using or over using TACC. I use it all the time and it, generally, takes advantage of places where it can maximize regeneration.
But, by far, in late fall through early spring heat is your biggest watt/hour stealer. Preheat the car while it's plugged in by turning on cabin heat 15 mins before you unplug and go. The same watt/hours are being used but it won't effect your mileage.

 

[Mr Miserable]

It's December, it's cold outside, so the last thing I want is Chill mode.

 

[Gava71]

Cold weather seems to be the worst enemy for energy consumption. Thankfully I live in central Florida and my consumption usually doesn’t go above 350 Wh. I have to really floor it to get to even close to 500 Wh.

 

[wcorey]

Cold weather seems to be the worst enemy for energy consumption. Thankfully I live in central Florida and my consumption usually doesn’t go above 350 Wh. I have to really floor it to get to even close to 500 Wh.

Surprisingly, even being in CT and AWD, I average since ownership (11/6/2018) 250 wh/mile! Yes, I was pleasantly surprised when I checked it Thursday.

 

[Gava71]

Surprisingly, even being in CT and AWD, I average since ownership (11/6/2018) 250 wh/mile! Yes, I was pleasantly surprised when I checked it Thursday.

Yes, the downside of having a fully warmed up battery in Florida is that you need to use the AC quite heavily and that is in detriment of the energy consumption. I’ve noticed that when I don’t have to use the AC at all (late fall/ winter and early spring) then consumption is also closer to 250Wh. So my conclusion is that both heating the battery or cooling the cabin will take a toll on the consumption, the latter is also true in an ICE as the AC runs off the engine and it will consume more gas that way. Still prefer EV, not going back to ICE.