Are these energy consumption normal?

[xuan]

Hi Everyone, I am not sure who else to ask, I have looked around the forum and googled a bunch as well, but I haven't been able to find a clear answer to my question.

In short, I picked up my Model S 75D around 1 month ago, and have been driving here in Toronto, Ontario, Canada for the past few month, mostly for my daily commute. I have noticed some very very high milage #'s, at first I thought it was normal cause it was crazy cold, but recently even though the temperature recovered a bit, I am still seeing these high milage #s, sometime I saw average of 425 wh/KM. The photo is what I am seeing currently, but hopefully gives an idea, it is slightly lower than what I normally saw. Normally, for my ~7Km commute, I would use 20+Km of milage, if not more.

This may very well be normal, but since I am a new owner, I just want to make sure there is nothing wrong with the battery before I have to make longer driving commitments.

Thanks all in advance!

 

[brkaus]

It's the cold and a short commute. Car heats up the batteries, then they cool off again before you head home and repeat.

I would suggest you preheat the interior and take a longer drive some day after you finish a "big" charge (below 50% to 90%) and see the numbers.

 

[jelloslug]

Preheat is your friend. In the winter time (if you can call what we get here "winter") I always plug in overnight so I can precondition while plugged in in the morning.

 

[xuan]

Thanks for the response.

I do actually pre-heat the car, it usually take an hour and 20km ish range away. When I do, I didnt see much improvement in the usage, but that might just be me. I just signed up for Teslafi after reading a bunch of forums, hopefully some actual data vs. my eyeballing will show something completely different .

 

[RichardD]

Those numbers look on par.
I get 250-300 driving in Houston but during cold snaps, it jumps to 350-400. Driving the same route and driving style.

 

[ran349]

Those numbers look on par.
I get 250-300 driving in Houston but during cold snaps, it jumps to 350-400. Driving the same route and driving style.

You do realize he's talking Wh/km, not Wh/mi, right?

 

[clostridium]

Thanks for the response.

I do actually pre-heat the car, it usually take an hour and 20km ish range away. When I do, I didnt see much improvement in the usage, but that might just be me. I just signed up for Teslafi after reading a bunch of forums, hopefully some actual data vs. my eyeballing will show something completely different .

When you preheat are you doing it while connected to shore power? I may be misreading your comment about how preheating takes 20 km of range away but it came across like you aren't hooked up to shore power when preheating.

Is the car in a garage (heated vs. unheated) or outside?

For really short trips like that if the car can't be preheated on shore power it's worth putting on range mode. That stops the car from using the battery heater as aggressively. You will end up with not much regen for the trip but it will save the sometimes substantial energy used to heat the pack which is basically wasted on a 7 km commute.

I suspect that the comments of others that this is the combination of a pretty short commute along with cold weather is the culprit. What happens when you drive longer distances? Getting Teslafi is a good idea since it makes it very easy to see your efficiency vs. temperature and filter out different length drives as well. It's also just a really nice resource to understand factors that influence efficiency due to all the information it provides.

Craig

 

[DwnSv]

I also have a S75 from December 2017, and live in The Netherlands. Although the weather hasn't been that cold the last few weeks (only one day of below 0 degrees Celcius), I also have radically different Wh/km consumption.

I agree that pre-heating helps a lot, as does driving longer distances (for the average rating that is). Saying that, I do always see a spike in my consumption meter for the first 5-10 km, but never that high (highest I think about 250 Wh/km). Is it possible to do a longer drive (say about 50 km) and see if that changes things?

Also, I've set my display on the lower left to percentage instead of range, as the range meter (rated to europe) assumes 200 Wh/km on average, and so in colder weather will definitely not make that.

 

[jdw]

At 8 degrees, that is a little high, assuming the car is fully warmed up, but I noticed you were displaying range over the last 50km, which may have included some colder weather, idle and parking time. Try setting it to 10 km as your commute is only 20 km.

 

[xuan]

Thanks to everyone who have responded

A quick update: (Sorry I can't modify the OP)

I pulled some data, granted its very limited samples, but with pre-head, I love data, and hopefully this gives a clearly picture of what I am describing.

 

[Darmie]

Last month going through Pennsylvania on RT80 starting out on a cold morning at highway speeds.

 

[xuan]

When you preheat are you doing it while connected to shore power? I may be misreading your comment about how preheating takes 20 km of range away but it came across like you aren't hooked up to shore power when preheating.

Is the car in a garage (heated vs. unheated) or outside?

For really short trips like that if the car can't be preheated on shore power it's worth putting on range mode. That stops the car from using the battery heater as aggressively. You will end up with not much regen for the trip but it will save the sometimes substantial energy used to heat the pack which is basically wasted on a 7 km commute.

I suspect that the comments of others that this is the combination of a pretty short commute along with cold weather is the culprit. What happens when you drive longer distances? Getting Teslafi is a good idea since it makes it very easy to see your efficiency vs. temperature and filter out different length drives as well. It's also just a really nice resource to understand factors that influence efficiency due to all the information it provides.

Craig

Thanks, I will give the range mode a try.

As for the pre-heating, in the morning, the car is in the garage, so pre-heating does not drain anything. I meant when I leave work, which do not have a charger, so it is not pluged in at that time, and normally took off 20KM. Also, I haven't had a chance to try longer drive yet, ( blame work ), will make it a goal to test that out this weekend.

But thanks for the response, I think you and everyone are right, it is probably due to the length of my commute and the weather. I will keep an eye on it, definitely need more data to make a more definitive call.

 

[hroussel]

Thanks to everyone who have responded

A quick update: (Sorry I can't modify the OP)

I pulled some data, granted its very limited samples, but with pre-head, I love data, and hopefully this gives a clearly picture of what I am describing.

View attachment 272718 View attachment 272719

I got my S 75D on Dec 13th in Montreal, at the beginning of the cold wave we got.

In town I'm easily getting 350 to 400 wh/km. I also have a short commute like you. Pre-heating doesn't make that much of a difference.

Today, even at 8-10C temps, I did a "best" of 300 wh/km in my commute. Regen was limited, indicating that some power was used to heat the battery.

On the highway things are much better. My worst consumption being 260 wh/km (on a 200km trip, at -24C with headwind). My best being around 230 wh/km (around -8C, slight tailwind).

Hopefully things will get better in the summer.

 

[TLej]

@xuan Totally normal. Assuming you can charge at home in the evening, not a big deal. Personally I disagree with using range mode; yes, it limits battery heating but it also limits climate control power and regen. When it’s cold enough to need to heat the battery, guess what’s nice to have? A warm car and a clear windshield, i.e. as much heat as you can get. Also, just like when warming up an ICE the engine warms up faster by driving, using power adds heat to the battery pack faster than the heater. I subscribe to the notion of doing a couple hard accelerations (keeping road and traffic conditions in mind) when starting out if possible. It heats the battery, and I also notice the heat from the heater is hotter just after a hard accel. Overall power consumption will still be higher in winter than summer, but whether you arrive home with 60% battery left or 40% doesn’t matter if you can just charge again overnight.

Highway driving, bit of a different story (do what you need to do to get where you’re going).