Charging beyond 90% daily

[WilliamG]

If you set temp to max and have AC on for 30 minutes, you’ll probably use 12.5kW (maybe only 9kW), based on that other post here. So 4.5-6.25kWh, which is 19-27 rated miles for your LR AWD.

It definitely makes no sense unless you are going to start with 2500 feet of steep downhill. Seems like kind of a corner case! There’s 4kWh of energy to reclaim there so might just start to make sense.

Speaking of kW usage, I charge to 80% daily at home. The iOS Stats app will show me how many miles an hour I’m charging. I found that on my 60A circuit (48A actual) that if I set my charge % to 85% (for testing so the car starts charging) and turned the heat on to 68F (from 51F ambient), my actual miles per hour of charging dumped to 32-34. If I turned the climate off remotely the rate immediately jumped back to 44 miles per hour.

Friend of mine has a 30A in the garage and he charges his car at 22 miles per hour. Under the same test conditions his rate changes to 11 miles per hour with climate on.

 

[AlanSubie4Life]

Speaking of kW usage, I charge to 80% daily at home. The iOS Stats app will show me how many miles an hour I’m charging. I found that on my 60A circuit (48A actual) that if I set my charge % to 85% (for testing so the car starts charging) and turned the heat on to 68F (from 51F ambient), my actual miles per hour of charging dumped to 32-34. If I turned the climate off remotely the rate immediately jumped back to 44 miles per hour.

Friend of mine has a 30A in the garage and he charges his car at 22 miles per hour. Under the same test conditions his rate changes to 11 miles per hour with climate on.

Yeah you would expect about 3kW for those conditions. Story checks out!

 

[Fresnel]

I've posted my situation a few times so some people may already know as everyone's been really helpful.

It finally decided to be Winter in Buffalo. I expect the avg temperature to be somewhere between 0-20 F for the foreseeable future.

My Wife commutes 100 miles round trip. Based on what she used when the weather was more mild 40-50 I think she's going to need as much of the battery as we can use daily. I've read so much about how to precondition and properly maintain the battery for longevities sake but in order for this car to do what we bought it for it seems about 10%-95% will just about do it in place of the 25-85 we have been keeping it at.

Would this be concerning over the long haul of ownership? Or should we realize that we are going to take a loss here and have to upgrade sooner than we expected?

I think the more long term thing you need to think about is this.. On one hand the battery is protected for 8 years to have above 70% degradation so if you really hurt the battery in those 8 years youll just get a new one... but the bigger problem I think youll run into is in a few years when your degradation is lower like 90% of your current capacity. Will you have enough battery to still do the 95% -10%? It'll be more like 95% - 0% after the 10% degradation loss. Worse case though you may have to make an extra supercharger stop in the work commute.

 

[Turlejay]

I think the more long term thing you need to think about is this.. On one hand the battery is protected for 8 years to have above 70% degradation so if you really hurt the battery in those 8 years youll just get a new one... but the bigger problem I think youll run into is in a few years when your degradation is lower like 90% of your current capacity. Will you have enough battery to still do the 95% -10%? It'll be more like 95% - 0% after the 10% degradation loss. Worse case though you may have to make an extra supercharger stop in the work commute.

There are no superchargers. Best she has is a level two about 75% of the way home. If we ever run into that bad of a situation we won't keep it but after the last few days even a 10% degradation won't be a problem.

 

[Turlejay]

easily the best she's done since taking the car to work. Obviously the outside temp helps a lot.

 

[Fresnel]

View attachment 503940 easily the best she's done since taking the car to work. Obviously the outside temp helps a lot.

Yeah that looks a lot better then the 95% - 10% you originally reported

 

[Turlejay]

Yeah that looks a lot better then the 95% - 10% you originally reported

It's a long thread lol, we have been past that a little while now.

 

[Fresnel]

It's a long thread lol, we have been past that a little while now.

Hmmm. I guess I should read the thread. I just read the first post and ignored everything.

 

[RickW]

I'm no expert here, but read the thread with interest.
I have found that there is a sweet spot for heating the car without expanding the kwh burn rate extensively above 300.
If I preheat the car (unplugged) for approximately 3-5 minutes to 70-71 deg F and drive the car at this temperature
with 2 out of the 4 vents open, and the driver and passenger seat heat set to 2, there is very little excess kwh used. ie for a 20 mile trip, regardless of outside temperature, I can get 5% battery loss and keep kwh to 295. (highway driving, no hills up or down and defrost off).

Once I increase the heater to say 74 degrees, then kwh jumps to 350-400 and the 20 mile trip will use up to 12% to get to the same destination. Same holds true if I use the defroster. There is a sweet spot under 71 degrees Fahrenheit when the Model 3, regardless of outside temps, seems to thrive more efficiently.

Again, I'm no expert, just an observation with an N=1. (Tested this with outside temps at 35 and 45 degrees).

 

[vogz]

BTW, most cold weather range degradation is from heating the cabin. Wear a sweater, use the seat heater, and keep the car at 60 degrees.

I don’t get why this is an accepted recommendation around here for daily use of a car. If I had reduce the comfort levels in my vehicle to make sure I got places reliably, I wouldn’t own the vehicle. Each to their own, but I’ll keep mine at 70-74F in the winter and be nice and warm.

 

[cstork]

BTW, most cold weather range degradation is from heating the cabin. Wear a sweater, use the seat heater, and keep the car at 60 degrees.

Ok, I agree, I got carried away. 60 degrees is a bit cold. But, you can do 68 instead of 72! If you are worried about range, this is a simple aid.
And give Tesla some credit: the preheat and the incredibly fast seat heaters are very nice.

 

[Turlejay]

I quit. After all this.

I tell wifey I bought her a wireless charge pad for her iPhone so she doesn't have to worry about cables. Her response "I don't even plug in because I don't want to use too much power"

But keep cranking the heat to 80 and lead footing it all the way home, but don't charge your phone. Riiiiight. This ring feels heavy fellas.

 

[ElectricIAC]

I quit. After all this.

I tell wifey I bought her a wireless charge pad for her iPhone so she doesn't have to worry about cables. Her response "I don't even plug in because I don't want to use too much power"

But keep cranking the heat to 80 and lead footing it all the way home, but don't charge your phone. Riiiiight. This ring feels heavy fellas.

Just curious but what kind of wh has she been averaging?

 

[Turlejay]

Just curious but what kind of wh has she been averaging?

I posted it earlier. She's doing fine, I just thought it was funny that of all things to worry about, it's her cell phone chargee

 

[dmurphy]

She left work today with 125 miles range. I think we figured it out. Thank you everyone. I love this community

Sounds like you got the entire situation under control. This is great! I don't know if they'd let her cable up at work, but even plugging into a 120V outlet for 8 hours would give her an extra ~30-32 miles of range. Plenty of extra margin if you've got any concerns, or she has other plans after work.

Good stuff!

There are no superchargers. Best she has is a level two about 75% of the way home. If we ever run into that bad of a situation we won't keep it but after the last few days even a 10% degradation won't be a problem.

Set the charger to 90% daily and forget about it. Good practice to keep the battery in balance is over 85%. All good. I suspect you won't be anywhere near 10% for many years to come, if ever ...

 

[Turlejay]

I have to take a trip to her building one day and see if I can scope out a 120v plug. She says there aren’t any, but I know her, and I’m sure she didn’t REALLY look. Would be worth it’s weight in gold if not just for sentry mode