100D range disappointment and experience- 'range anxiety'?

[wp746911]

We have a ~1 month old MX 100D. I bought it for my wife. She is loving it and I love it too- great for around town. She had to drive from our house (Jackson, MS) to Memphis, TN by herself early one morning.
- I set the battery to 100% and left it plugged in until right as she was driving. Showed 295/296 miles range.
-The trip computer estimated a 204 mile trip with ~10% mileage left when she reached her destination.
-The car was garaged so it was maybe 60 degrees when it started, outside temp around 45-50.
- Range mode was OFF.
-I discussed the impact of speed on range to her (she loves to drive 80)- and we said that going around 75 should be ok.

So- she left our house around 5am. She went a few miles to I-55 and when she got on i-55 and got past 70 mph and the car beeped at her and said that she needed to stay below 70 to make the trip (going <70 on I-55= death wish). I then got an annoyed phone call- she had planned on driving nonstop to memphis. We discussed options and she ended up driving closer to 80 and stopped in Grenada, MS for the supercharger there. She spend 20 minutes and got about another 90 miles range and finished her trip no problem.

Now if it were just me, I would have planned on going fast and stopping in the SC in the first place. Or I would have just driven and listened to the car and seen how it went. Any advice?? She's pretty disappointed in the range. She was really planning on a nonstop trip and I encouraged her to take the Tesla (over our Acura MDX). I understand t

 

[MorrisonHiker]

We have a ~1 month old MX 100D. I bought it for my wife. She is loving it and I love it too- great for around town. She had to drive from our house (Jackson, MS) to Memphis, TN by herself early one morning.
- I set the battery to 100% and left it plugged in until right as she was driving. Showed 295/296 miles range.
-The trip computer estimated a 204 mile trip with ~10% mileage left when she reached her destination.
-The car was garaged so it was maybe 60 degrees when it started, outside temp around 45-50.
- Range mode was OFF.
-I discussed the impact of speed on range to her (she loves to drive 80)- and we said that going around 75 should be ok.

So- she left our house around 5am. She went a few miles to I-55 and when she got on i-55 and got past 70 mph and the car beeped at her and said that she needed to stay below 70 to make the trip (going <70 on I-55= death wish). I then got an annoyed phone call- she had planned on driving nonstop to memphis. We discussed options and she ended up driving closer to 80 and stopped in Grenada, MS for the supercharger there. She spend 20 minutes and got about another 90 miles range and finished her trip no problem.

Now if it were just me, I would have planned on going fast and stopping in the SC in the first place. Or I would have just driven and listened to the car and seen how it went. Any advice?? She's pretty disappointed in the range. She was really planning on a nonstop trip and I encouraged her to take the Tesla (over our Acura MDX). I understand t

If you use a site such as A Better Routeplanner , you can better plan different trip scenarios in advance.

 

[Yggdrasill]

I believe the navigation will start to complain once the expected SOC at destination drops below 10%. So, even a 1% drop in expected SOC at destination would cause it to complain. That doesn't mean the car can't do the trip - it just means that it doesn't expect you to have the spare margin it is set up for. Also, there may be up to 10 miles of additional range below 0% (but don't count on that).

Time-wise, going faster is better up to around 90 mph. Above 90 mph you need to spend more time charging than the time saved driving faster. Also, there's no need to charge for 20 minutes if 5 minutes is enough.

200-ish miles of range at 80 mph doesn't sound entirely implausible. There could be a head-wind impacting range. And what tires/rims does it have? 19" is better for range.

 

[Super_Popular]

Don't drive 80 or even 70 mph, you just cant do that if you are worried about range in a Model X.

 

[Big Earl]

A trip like that should have included a Supercharger stop to begin with. 200 miles straight is a bit of a stretch in the winter.

 

[ba2002]

I dont think the current range in the model X is great for fast, non-stop trips. Either plan on supercharging or take your ICE. You're lucky it's that warm.

 

[posity]

I would just chalk this up to learning about EVs. Range is a VERY rough number in any electric car - you just have to get used to this concept. There are numerous variables that have large effects on range:
1) Elevation change
2) Your speed
3) Temperature
4) Use of heater
5) Driving style
6)...
So if you use software like abetterrouteplanner, it tries to factor in some of these variables to give you a more accurate estimate of your range for your specific destination and route. If instead you want to just say 'I have X miles to go', and not actually use software to plan ahead, then you will be scratching your head about your actual range for the rest of your ownership.

 

[RichardL]

I have found that the algorithm that generates that warning message is often fooled by a variation as you start going.

Essentially it builds a plan of your expected usage (what you see on the Trip graph). But if you start out and in the first few miles exceed the plan (and simply starting from zero and getting up to speed will do that as it works out a steady state plan) you use much more energy over the first couple of miles and it immediately starts to warn you. As you do more miles the 'error' goes away and it is happy - usually overall it is pretty accurate I find, but I have often had the warnings to begin with.

I have a 90D and often do the 196 miles from my house to the Kettleman City SC with no issue and have around 25-30 miles left. I usually drive 72 - 75

 

[jboy210]

Speed is the killer of mileage (actual wind resistance that grow quickly). Remember the EPA mileage they put on the window sticker of any car is based on the EPA test highway test cycle which has a max speed of 60 MPH. See Detailed Test Information and click the "Highway" tab to see the speeds and durations for the dyno runs

 

[MorrisonHiker]

I have found that the algorithm that generates that warning message is often fooled by a variation as you start going.

Essentially it builds a plan of your expected usage (what you see on the Trip graph). But if you start out and in the first few miles exceed the plan (and simply starting from zero and getting up to speed will do that as it works out a steady state plan) you use much more energy over the first couple of miles and it immediately starts to warn you. As you do more miles the 'error' goes away and it is happy - usually overall it is pretty accurate I find, but I have often had the warnings to begin with.

I have a 90D and often do the 196 miles from my house to the Kettleman City SC with no issue and have around 25-30 miles left. I usually drive 72 - 75

Yeah, I ran into this myself on my first few road trips. Immediately after leaving a Supercharger and using a lot of energy to get back up to speed on the interstate, it would assume I wouldn't have enough battery power. I think they've tweaked the algorithms some since then but it can still happen from time to time.

 

[Brass Guy]

Did you pre-heat the car while it was still plugged in? The use of cabin heat takes quite a lot of energy, especially initially. I'd imagine heating a Model X takes more than a Model S too. 45-50 is not that cold, but if the cabin was set to 75F or so, that'd prevent a non-stop trip right there.

 

[wp746911]

Regarding range mode- will that help much? I had it off.

Thanks for the comments!!- thumps up to you all as you are all very helpful. Things I'm taking from this:
1) A SC stop is a good idea. I would have planned it from the beginning but she wanted to avoid it.
2) I did NOT preheat the car. Next time I will definitely do that when its plugged in.
3) I'll wait and watch the range once I'm highway cruising.

I think we'll get better as we use it more. I obviously don't want the wife stranded by the side of the road at 6am- so we'll be cautious for now. Thanks again for all your responses!

 

[ajdelange]

We have a ~1 month old MX 100D. I bought it for my wife.

I'm in exactly the same situation except that the claim that I bought it for Mrs. is a lie. The point really is that we have a lot to learn about what the displays and numbers mean. That is coming on pretty quickly but it is going to take some time. I find myself thinking more and more in the mode that I used to think when planning a flight than when planning a road trip. A pilot has to get to an airport (with margin) to refuel. A Tesla driver has to get to a charger (with margin) to refuel. A pilot has to be cognizant of how temperature and wind effect his ability to get to an airport and the Tesla driver must consider those things too.

- I set the battery to 100% and left it plugged in until right as she was driving. Showed 295/296 miles range.

The car doesn't know anything about how you are going to drive or what kind of weather you are going to drive in but as you obviously want some indicator of the range you may get from a charge, used "rated" consumption to turn % SoC into expected miles. Evidently the rated consumption is 100,000/295 = 339 Whr/mi.

The graph below shows actual consumption rates achieved by Model X drivers at temperature between 30 and 60 °F (not so sure on the upper limit) who allowed ABRP to collect data from their cars as they drove them. As you can see from the curve the 339 Wh/mi performance number pertains to operation at the "sweet spot" i.e. around 40 mph.

At 80 mph the graph shows consumption of 464 Wh/mi for a range of 100000/464 = 216 miles
At 75 mph the graph shows consumption of 432 Wh/mo for a range of 100000/432 = 231 miles.
Note that this does not mean that you would get those ranges at those speeds. That depends on conditions. Those rangers are what the average driver in the ABRP data base got.

-The trip computer estimated a 204 mile trip with ~10% mileage left when she reached her destination.

That says the car is using 90,000/204 = 441 Whr/mi corresponding to a speed of about 75 mpH on the graph. It has knowledge of terrain and speed limits along the route so it is able to consider those in computing expected battery drain. Note that it does not use the model implied by the graph. It uses whatever model it has deduced from data collected by Tesla.

So- she left our house around 5am. She went a few miles to I-55 and when she got on i-55 and got past 70 mph and the car beeped at her and said that she needed to stay below 70 to make the trip (going <70 on I-55= death wish).

That may seem contradictory as the planner told you that the trip could be made with 10% margin knowing that I-55 was going to be used. As the speed limit is 70 on I-55 that's what the route planner would have used. The ABRP data indicates that an increase of speed from 70 to 75 would cost 7% more energy per mile and an increase to 80 would imply an increase in consumption of 17%. That easily explains how 10% margin for a trip planned at 70 mph could turn into a deficit if the trip is executed at higher speed. Another thing to consider is that the navigation system is monitoring battery draw. If, for example, she encountered a 10 mpH headwind while driving 75 that is equivalent to driving at 85 which means an increase in consumption of 24% relative to what was planned for at 70 mph. The navigation system would detect the higher than planned battery draw and issue the alert. Also a temperature drop of 20°C causes an increase in drag of about 12%. Thus her experience hardly seems unusual.

As you are so new to the car you may not have discovered the touchscreen's energy monitoring graph. If you have planned a trip it will show you what it originally thought the energy consumption profile was going to be and what the consumption has actually been based on what it has measured during the trip. If a headwind is encountered, for example, the fact that you will arrive at the destination with less battery than you had planned on, or not at all, will be displayed. I believe that it will reroute to a SC along the way in the latter case but have not experienced that.

Any advice??

Think a bit along the lines I've suggested above. Play around with A Better Route Planner to see what the effects of things like temperature, speed, terrain and load can be. Use the energy monitor and trip meters whenever driving the car to learn how consumption changes when you turn on the heater, accelerate rapidly, use the brakes (as opposed to regen), open the windows, take your anvil collection to an anvil collectors show etc. Getting savvy on all this may prevent the annoyed phone calls but cannot change the fact that sometimes you aren't going to do as well as you'd planned and may have to insert an extra charging stop (or 2). OTOH sometimes you will do much better (good tail wind). Monitor what is going on whilst driving and be prepared to react as necessary.

 

[PJFW8]

Regarding range mode- will that help much? I had it off.

Thanks for the comments!!- thumps up to you all as you are all very helpful. Things I'm taking from this:
1) A SC stop is a good idea. I would have planned it from the beginning but she wanted to avoid it.
2) I did NOT preheat the car. Next time I will definitely do that when its plugged in.
3) I'll wait and watch the range once I'm highway cruising.

I think we'll get better as we use it more. I obviously don't want the wife stranded by the side of the road at 6am- so we'll be cautious for now. Thanks again for all your responses!

Preheating makes a difference on general battery performance and avoids the loss due to bringing cabin up to temperature. headwinds are a big deal, especially in the Model X.

 

[David29]

Regarding range mode- will that help much? I had it off.

Thanks for the comments!!- thumps up to you all as you are all very helpful. Things I'm taking from this:
1) A SC stop is a good idea. I would have planned it from the beginning but she wanted to avoid it.
2) I did NOT preheat the car. Next time I will definitely do that when its plugged in.
3) I'll wait and watch the range once I'm highway cruising.

I think we'll get better as we use it more. I obviously don't want the wife stranded by the side of the road at 6am- so we'll be cautious for now. Thanks again for all your responses!

One other thing that might have helped you understand how well the car was forecasting energy use and how close she came to needing more juice than she had -- if she or you had noted the total consumption and Wh/mi for the trip, and even for the separate legs of the trip. Then, in reviewing the trip afterwards, you'd have had hard data on what actually happened. Very helpful for learning the effects of cold, speed, elevation, etc. Use the trip data tab to view the energy usage and Wh/mi (and use the small energy panel in the instrument cluster to keep track as you drive).

 

[ajdelange]

Did you pre-heat the car while it was still plugged in? The use of cabin heat takes quite a lot of energy, especially initially. I'd imagine heating a Model X takes more than a Model S too. 45-50 is not that cold, but if the cabin was set to 75F or so, that'd prevent a non-stop trip right there.

At first I blamed the heater for the "departure tax" but a little thinking shows that the heater is probably not really to blame. If you estimate the volume of the cabin, compute the mass of the air it contains and consider reasonable rises you will find that it only takes perhaps 100 Whr to heat the cabin air. Observations of the current draw with the heater on seem to indicate that once the cabin is at temperature the heater is drawing perhaps 1.5 kW. Assuming a speed of 60 mph a 1 hr (60 mi) trip will use 1500 whr to keep the cabin warm but about 60*358 = 21487 Whr for traction. Adding the heater's contribution to the departure tax gives a total of 1600 Whr for the heater which is 7% if the traction demand. The heater's departure tax consideration is only half a percent. So the advice to be sure to pre-warm when on shore power if possible is not really that valuable (but I always do it anyway). Better advice is to keep the heat down or, as the manual advises, see if the seat heaters can keep you comfortable.

Recently I've come to realize that of the 21.487 kW the car is apparently pulling from the battery when going 60 mpH about 10% is being dissipated as heat in the transistors in the inverters, the rotors, the bearings etc. That 2.1 kW is equivalent to 7162 BTU/hr (or about 0.6 ton) of heating. That heat has to be disposed of to prevent damage from overheating and so at least some of it (I don't know how you'd collect it from bearings and the rotors) is carried away from the inverters by the coolant system. In the summer the coolant heat is dumped overboard but in the winter it is doubtless dumped into the cabin. In the winter that heat is going to go to warm the battery but once the regen dashed lines are off the effect of the heating system on range should be reduced. To capture that available heat more rapidly and thus increase range keep the garage warm so the battery doesn't require much heat from the inverters to get it warmed when you start out. A couple of small unit heaters aimed under the car might just do the trick.

My advice in this regard is preheat on shore power and beyond that keep the heat where you are comfortable but always be aware of your energy status and be prepared to make adjustments if necessary.

 

[shrfu31]

Even the trip planner on Tesla's website said to incorporate a stop. It's always good to check things and set proper expectations. That being said, I don't use the mileage in the car at all. I switch it to percentage and multiply.

In cold weather take your battery percentage and multiply by 2 to get your approximate range in miles. In warm weather multiply by 3. Simple and so far been invaluable when planning these minor winter road trips.

 

[Kant.Ing]

OP, hope your wife complains only about the car and not you!

My quick advice and good practice is to use the in-car navigation, with the destination set to a destination charger or Supercharger around where you plan to stay, and start monitoring the percentage number which indicates the estimated battery capacity at the charging stop(s). Some people like to start with 20% and keep the number above 10%, and I am comfortable starting with 5~10%. The number should be always positive, and its changing tells you how efficient your driving is--if the percentage number drops and drops to your anxiety zone, slow down, look further, and drive less aggressively, and if it increases, you know you have some luxury to speed or to detour.

I have seen the car's estimation very conservative at the beginning of the trips, as I can always recover some points en route or before entering highway, even without preheating. I also found the car's estimation takes elevation changes into account and so it's like a real-time ABRP.

However if you guys want absolute speed (or minimizing overall time spent) over a long trip, drive an ICE or a hybrid.

FYI a quick conversion from percentage to mileage is to divide the percentage number by .4. For example, 16% means 40 miles and 7% means 20 miles for our car, YMMV. Numbers in miles don't look scary at all!

 

[Lasttoy]

Posity has it right.
I've got 131k miles on my S. Driven in over 25 states and cities.
There way to many variables to ever calculate the miles.
I.e., i do a 100 mph run to Jax , 45 miles, it uses 75 miles of charge. Tesla seems to have set optima mileage at 70mph with cruise cohtrol.
I go to DC often. Never ever get same numbers.
If you are going on long trip? Charge to full, and let car tell you when to charge.

 

[Rocky_H]

A SC stop is a good idea. I would have planned it from the beginning but she wanted to avoid it.

This comes up on this forum again and again with new owners, and I just don't get it. What is it with people's obsession to avoid using the most cheap, convenient, fastest charging that exists on planet Earth? In a 3 hour drive, I'm not sure what people think is so awful about a 15 minute break in the middle somewhere.