100% charge or 90 or 95?

[hpartsch]

Or the OP's wife does not work and the OP stroked the check to Tesla. Regardless, either scenario is irrelevant in solving/answering the OP's question/concern.

For the OP, note that the in-car navigation is generally pretty pessimistic in calculating the level of charge at the end of the trip. For example, on my last long trip my car warned me to stay below 70mph to reach my destination. At the end of the trip I arrived with 22% charge. Unless it's incredibly cold and/or you are climbing a mountain and/or you are driving with a significant headwind, you should do better than the navigation predicts you will.

As you and your wife drive, you'll acclimate to these things and you'll be able to account for them without getting range anxiety, especially if the trip is one you take frequently.

From the OP: "commute is a real 225 miles per day to work and back".

 

[GreggF1]

Thank you for all the input. To clarify a few things... I insisted on the purchase of an EV due to mileage driven, fuel, and maintenance considerations. We researched and researched this car. WE decided to purchase a Model S. After talking with a handful of friends that own them, and some sales people, we were convinced buying the Performance model as well as FSD would ultimately pay for itself in value retention. Please don't discount the fact my wife is also a sports car aficionado. She got rid of her Jaguar F-Type R for the Model S so she is no stranger to performance cars and a desire to drive them. We also own a 600HP AMG.

With a 120 mile each way commute Rockford to Chicago - we were assured this vehicle will make the trip - even in winter. Being new to EV, we both share range anxiety because of this 90% charge "advice" the 90% makes the commute dicey. 100% or even 95% is non-issue

Today's commute in 63F weather was good... she started at 90% charge with 313 range. She arrived home with 50 miles remaining. So good weather she is seeing 90% - 15%

With this 90% - 15% in good weather... when winter sets in and we are in 30F temps... do we:

1. Charge to 95%
2. Charge to 100%
3. Charge at work if her range is <45%

 

[ucmndd]

With this 90% - 15% in good weather... when winter sets in and we are in 30F temps... do we:

1. Charge to 95%
2. Charge to 100%
3. Charge at work if her range is <45%

Likely all of the above depending on the day's circumstances. I don't want to scare you unnecessarily but I will caution again that you are likely drastically underestimating your efficiency loss in cold weather.

I'm in an area of California that gets "cold" in the winter (overnight lows in the 30s, occasionally 20s), but not "Chicago cold". For reference, I get ~315wh/mi on my 120 mile round trip in the summer, almost every trip. During the winter my average is 350wh/mi - 10% efficiency loss.

You should be planning for 2-4 times that depending on the day. Cold and wind will decimate your range. Regular deep cycles of your battery and charging past 90% are going to accelerate degradation - 90% isn't going to be "313 miles" for long.

 

[Fred42]

Thank you for all the input. To clarify a few things... I insisted on the purchase of an EV due to mileage driven, fuel, and maintenance considerations. We researched and researched this car. WE decided to purchase a Model S. After talking with a handful of friends that own them, and some sales people, we were convinced buying the Performance model as well as FSD would ultimately pay for itself in value retention. Please don't discount the fact my wife is also a sports car aficionado. She got rid of her Jaguar F-Type R for the Model S so she is no stranger to performance cars and a desire to drive them. We also own a 600HP AMG.

With a 120 mile each way commute Rockford to Chicago - we were assured this vehicle will make the trip - even in winter. Being new to EV, we both share range anxiety because of this 90% charge "advice" the 90% makes the commute dicey. 100% or even 95% is non-issue

Today's commute in 63F weather was good... she started at 90% charge with 313 range. She arrived home with 50 miles remaining. So good weather she is seeing 90% - 15%

With this 90% - 15% in good weather... when winter sets in and we are in 30F temps... do we:

1. Charge to 95%
2. Charge to 100%
3. Charge at work if her range is <45%

I hope you consider the suggestion in the previous post to switch to 19 inch wheels if you have 21's.

 

[Country Roads]

Thank you for all the input. To clarify a few things... I insisted on the purchase of an EV due to mileage driven, fuel, and maintenance considerations. We researched and researched this car. WE decided to purchase a Model S. After talking with a handful of friends that own them, and some sales people, we were convinced buying the Performance model as well as FSD would ultimately pay for itself in value retention. Please don't discount the fact my wife is also a sports car aficionado. She got rid of her Jaguar F-Type R for the Model S so she is no stranger to performance cars and a desire to drive them. We also own a 600HP AMG.

With a 120 mile each way commute Rockford to Chicago - we were assured this vehicle will make the trip - even in winter. Being new to EV, we both share range anxiety because of this 90% charge "advice" the 90% makes the commute dicey. 100% or even 95% is non-issue

Today's commute in 63F weather was good... she started at 90% charge with 313 range. She arrived home with 50 miles remaining. So good weather she is seeing 90% - 15%

With this 90% - 15% in good weather... when winter sets in and we are in 30F temps... do we:

1. Charge to 95%
2. Charge to 100%
3. Charge at work if her range is <45%

How about option 4 - charge to 85% in the morning, arrive at 40%, plug in at work, and charge back up to 85% for the drive home?

 

[GreggF1]

I hope you consider the suggestion in the previous post to switch to 19 inch wheels if you have 21's.

Assuming I would have to recalibrate the speedo then? There would be no advantage to going smaller wheels and taller tires ie: matched circumference to range?

 

[Fred42]

Assuming I would have to recalibrate the speedo then? There would be no advantage to going smaller wheels and taller tires ie: matched circumference to range?

An S with Tesla's 19 inch wheels and tires will have longer range than it does with 21. The tires have more sidewall with 19. Not sure about the speedo.

 

[TechNeutral]

Assuming I would have to recalibrate the speedo then? There would be no advantage to going smaller wheels and taller tires ie: matched circumference to range?

The 19” rims have better aerodynamics but the big difference is the lower rolling resistance on the stock tires for the 19’s. The sticky summer tires on the 21” rims just destroys your range. Also Tesla can easily update the software for the 19” rims and it will even update the renders in the vehicle.

 

[GreggF1]

The 19” rims have better aerodynamics but the big difference is the lower rolling resistance on the stock tires for the 19’s. The sticky summer tires on the 21” rims just destroys your range. Also Tesla can easily update the software for the 19” rims and it will even update the renders in the vehicle.

I wonder if they can do the update by wire... or if I need to take it in. I hate paying people to work on my car when I can do it myself.

 

[outdoors]

I wonder if they can do the update by wire... or if I need to take it in. I hate paying people to work on my car when I can do it myself.

You can do it yourself. Prior to the update customer service would do it. When you could talk to someone on the phone.

 

[GreggF1]

Interesting - just checked and our car came with 19" wheels... odd. I wonder if someone jacked those at the dealer? Brand new Model S Performance... I thought you could only get 21"

 

[outdoors]

348 for 19's 326 for 21's. Both an option on the performance currently. Swap them out.

 

[TechNeutral]

Interesting - just checked and our car came with 19" wheels... odd. I wonder if someone jacked those at the dealer? Brand new Model S Performance... I thought you could only get 21"

They sell them with the 19’s and the 21’s new. So I wouldn’t be too concerned about that, but unfortunately it does mean no magical range boost by installing 19’s.

 

[outdoors]

They sell them with the 19’s and the 21’s new. So I wouldn’t be too concerned about that, but unfortunately it does mean no magical range boost by installing 19’s.

Seems magical enough for me if the OP has a desire to swap out rims with someone else that might want 21's.

 

[TravelFree]

Disagree. According to Tesla leaving the battery at 100% long-term is not healthy for it. 90-20 is not a problem.

Here's a suggestion if you did charge to 100% and discover your travel is delayed.

Open your app and turn on climate control and add heater or AC to start draining your battery down from 100%. You'll be surprised how much that uses.

Also, I would really like to learn how anyone can leave their Tesla at 100% of charge considering the phantom discharge. Unless you are keeping the charger connected and on all the time. My MS will begin to discharge 1-2mph per hour as soon as I stop charging at home.

 

[Rocky_H]

With this 90% - 15% in good weather... when winter sets in and we are in 30F temps... do we:

1. Charge to 95%
2. Charge to 100%
3. Charge at work if her range is <45%

How about option 4 - charge to 85% in the morning, arrive at 40%, plug in at work, and charge back up to 85% for the drive home?

5. There is a Tesla Supercharger literally just 1,222 feet away from Interstate 90 in Rolling Meadows, on the way home to Rockford.

 

[hgmichna]

As for my first-hand knowledge on this subject, I commute 120 miles per day in an S75, that had a range when new of 249 miles. Usual duty cycle is 90% -> ~30%. Three years and 110,000 miles later, my 100% range is now 218 miles, for ~12% degradation.

80% => 20% might have been easier on the battery than 90% => 30%.

And you can reduce battery wear at low states of charge by driving more slowly, i.e. when you get below 20%, reduce your speed gradually and don't accelerate wildly (to keep cell voltage from going very low).

 

[hgmichna]

Assuming I would have to recalibrate the speedo then [with a different tire size]?

I don't know, but I bet it always calibrates itself from the GPS, so no problem.

 

[beatle]

I suggest also getting a subscription to TeslaFi to track your consumption. It will even provide graphs of your efficiency based on temperature. It doesn't change the facts, but it allows you to track them.

Here's a suggestion if you did charge to 100% and discover your travel is delayed.

Open your app and turn on climate control and add heater or AC to start draining your battery down from 100%. You'll be surprised how much that uses.

Also, I would really like to learn how anyone can leave their Tesla at 100% of charge considering the phantom discharge. Unless you are keeping the charger connected and on all the time. My MS will begin to discharge 1-2mph per hour as soon as I stop charging at home.

I don't believe anyone would keep their car at 100%, but while plugged in, it will start to recharge if it has lost ~3% of its charge while idling.

 

[Country Roads]

Looking at this commute on ABetterRoutePlanner.com - Rockford to Chicago and back:
A Better Routeplanner

Lots of superchargers available. The car's computer will guide her and she will get comfortable with cruising in with low miles left because she has ample opportunities to bail out.

So the question remains, what's better for the battery - a deeper discharge to 10-15%, or a daily supercharger boost of 20% in 10 minutes?

A Better Route Planner let's them gamify things. They can dive deep into the settings and add winter temps, higher consumption, etc.