My Trip and Range math does not work.

[kerch2007]

Good afternoon,

I would like to better understand the Indicated Range and Trip screen. I know about vampire drain, but I wonder if this is normal. Yesterday's morning, the car was showing 181 miles. This moring - the remaining range was 87 miles and distance since last charge was 78. 23.4 KWh used. 300 Wh/m.

Is it possible for vampire drain to "steal" 16 miles overnight. It was cold though - about 50 degrees at night time and I used heater in the morning.

What's the best way to validate true energy consumption? For 2217 miles, I've used 714.8 kWh, 322 Wh/mi.

Thank you

 

[Seawind300]

The 50* , the pre-heating and a cooled battery sitting at 50* can easily add up to 16 miles. As the battery pack heats up with driving, you may get a few miles back. Can you plug the car in at night? A plugged in Tesla is a happy Tesla. I keep mine between 70% and 85%,

Mike

 

[kerch2007]

Cant plug it ay home unfortunately...using urban superchargers nearby

 

[N..8]

It depends on starting temp of battery and how much you are driving but the battery heater can use anywhere up to 6kWh of battery or even more. The heater is 6 kW.

 

[Olds442]

Cant plug it ay home unfortunately...using urban superchargers nearby

can't even plug into a normal 120v plug? cold will vampire drain faster than most people think. 16 miles isn't a surprise.

 

[dark cloud]

Lately, with the air temp around 0 degrees C (32 F) our daily commute is about 65 km yet 100 km of range disappear from the battery. This of course means a cold car warms up twice; once from about 7 degree garage to work and once from outside parking lot at 2-3 degrees to back home. It doesn't matter much if it is plugged in overnight or not. Typically I loose 1% or about 4-6 km overnight. But I have seen up to 30 km lost overnight in the past. I still don't know why/the reason sometimes the large vampire drain happened.

It's not much different to an ice. With our previous road trip vehicle Infiniti QX50, after filling up and driving conservatively down a hill, the trip meter taking into consideration the latest consumption over the previous few km stated a range of 700 km. A few hard accelerations on flat land and you see it fall to 400 km very quickly.

What is the odd part is people didn't care (myself included) when it was a gas car: you just filled up when the gas tank got low, and not many paid attention to the range, or the tiny little factors which influenced it. All of a sudden we get an electric vehicle and we start turning off the a/c, not using the heater to get increased range because some program using ideal conditions suggests what the range could be. I never drove on "range mode" in the Infiniti and turned down the heater etc. to try to get 700km out of tank of gas.

Like most experienced electric vehicle operators you learn to not worry about the rated range and instead switch to the percent state of charge instead. Now leaving from a plugged in 80% SOC getting back home with about 55%. Repeat tomorrow and don't think about it.

 

[TMeister]

Like most experienced electric vehicle operators you learn to not worry about the rated range and instead switch to the percent state of charge instead. Now leaving from a plugged in 80% SOC getting back home with about 55%. Repeat tomorrow and don't think about it.

This. True, true.

 

[Rocky_H]

Like most experienced electric vehicle operators you learn to not worry about the rated range and instead switch to the percent state of charge instead. Now leaving from a plugged in 80% SOC getting back home with about 55%. Repeat tomorrow and don't think about it.

I highly disagree with that. You, like many others, are mashing together two different things as if they are one thing:
(1) Not worrying
(2) Don't let yourself see information.

You're saying that for anyone to have the capability of not worrying, they need to not have the useful information of the rated miles number. I would suggest that I and others can have the emotional capacity to not have obsessive paranoia and worry, while still seeing and using the rated miles number. Turning it to % is kind of like a crutch, so you just get into "ignorance is bliss" by not having access to that information if it's going to excessively bother you. It is possible for people to drive 100 miles and see that 120 or 140 rated miles got used up and not freak completely out about it. But as we see on this forum, that is something that doesn't always come easily to new EV drivers. That is sometimes a developed behavior of "experienced electric vehicle operators"--to be comfortable with rated miles depleting more quickly than real miles. That's hard for some.

 

[Babaron]

I switched to % battery a long time ago and said bye bye to range anxiety. It is not hiding data, but rather viewing different data. If I have any question about range miles left, I display the Energy app and it gives me an accurate estimate of my actual range left.

Also, when using Nav, it gives me the est. % charge left at arrival. I find this very useful use of a different kind of data.

 

[Olds442]

I switched to % battery a long time ago and said bye bye to range anxiety. It is not hiding data, but rather viewing different data. If I have any question about range miles left, I display the Energy app and it gives me an accurate estimate of my actual range left.

Also, when using Nav, it gives me the est. % charge left at arrival. I find this very useful use of a different kind of data.

alternative data.

side note: i was a "charge to 60%, save the battery, save the dream" guy but have since gone to 90% as tesla recommends. every day the p85 charges to an additional mile at 90% so I know BMS is adjusting range back in my favor. up to 227 at 90% and in a couple days, it'll be 228. charging to 60-70% every night does you no favors, it will give you range anxiety as it did a lot of us.

 

[Rocky_H]

but have since gone to 90% as tesla recommends.

The sales staff recommends 90%. They say that because it's one consistent recommendation they can give to everyone without having to know people's individual situations about driving distances and home charging speeds. It's not what's best for the battery, but telling people to use lower charging limits and then having people run out of driving range and having to get towed or being pissed off and ranting on social media about how deficient the cars are and how "Teslas suck", etc. is a P.R. black eye they just don't need. Elon Musk and Jeffrey Dahn have said before that lower percentages are more ideal for the battery, but having the sales people recommend 90% is going to be a pretty insignificant difference in battery health, but keeps people away from worrying whether they will have enough range.

 

[Olds442]

Elon Musk and Jeffrey Dahn have said before that lower percentages are more ideal for the battery, but having the sales people recommend 90% is going to be a pretty insignificant difference in battery health, but keeps people away from worrying whether they will have enough range.

just so i understand what you are saying, "charging to 90% is going to be a pretty insignificant difference in battery health, but keeps people away from worrying whether they will have enough range?"

and you disagree with 90%? i'm completely confused by your disagree to my post and subsequent response. i am truly not trying to be confrontational, i genuinely don't see where we aren't saying the same thing. very best.

 

[Lukez]

Well doesn't it depend on your daily usage though? Saying charging to 60 70 80 or 90 is misleading.
If you use 40% daily charging to 90% daily is much better than 60% daily.
I think tesla sales should recommend keeping your battery % in that daily range area throughout the day.

 

[dark cloud]

I just keep thinking if Tesla had given us a battery level meter gauge like an ice, a dial displaying full, 3/4, half, and 1/4 with a dummy light when it got within 1/10 of complete charge, instead of a state of charge "accurate" to 1 km, none of these threads would exist.

 

[Eevee]

What is the odd part is people didn't care (myself included) when it was a gas car: you just filled up when the gas tank got low, and not many paid attention to the range, or the tiny little factors which influenced it. All of a sudden we get an electric vehicle and we start turning off the a/c, not using the heater to get increased range because some program using ideal conditions suggests what the range could be. I never drove on "range mode" in the Infiniti and turned down the heater etc. to try to get 700km out of tank of gas.

Then you were never poor. Or never an energy conservationist.

Plenty of people who drive ICE cars DO in fact pay a lot of attention and have been driving in ways that conserve energy for a long time. When gas prices suddenly increase, you will see more ICE drivers do things like condense shopping trips, use their a/c or heater less, driving slower and coasting into stops instead of slamming on the brakes last minute... and all those hybrid drivers? They don't have range anxiety but they often drive in ways that conserve energy.

 

[Rocky_H]

just so i understand what you are saying, "charging to 90% is going to be a pretty insignificant difference in battery health, but keeps people away from worrying whether they will have enough range?"

and you disagree with 90%? i'm completely confused by your disagree to my post and subsequent response. i am truly not trying to be confrontational, i genuinely don't see where we aren't saying the same thing. very best.

Your comment had a lot more in it than just that. Let's look at this part:

charging to 60-70% every night does you no favors, it will give you range anxiety as it did a lot of us.

You said right here that charging to a lower level has no benefit at all, and that doing it "WILL give you range anxiety". Period. No exceptions. That is quite a false assumption/accusation which doesn't necessarily apply to everyone and was worthy of a disagree.

The one size fits all recommendation isn't always the best fit for everyone. My drive to work is 2 miles. I go two or three days of driving around town before I would even get down to half full. Using an extra high daily charge level like 90% has no range benefit for me, and is just unnecessary faster degradation on the battery. Using 70% or 80% still gives me way more range than I need, has no range anxiety, and is a little better for the battery.

Here's a decent analogy. It's very like you are recommending everyone poke a hole in their skin with a needle every day. Many people would say, "Why? That hurts, and I can't see any need for it."
You respond: "It won't kill you. It's an insignificant injury, and you'll heal from it, and some people really need to do that to measure their blood sugar because they're diabetic."

See? How about the diabetic people who need to do that and have some benefit from it, get recommended to do that, but for people who don't have a benefit to doing it, get to avoid it?

 

[Olds442]

Your comment had a lot more in it than just that. Let's look at this part:
1
You said right here that charging to a lower level has no benefit at all, and that doing it "WILL give you range anxiety". Period. No exceptions. That is quite a false assumption/accusation which doesn't necessarily apply to everyone and was worthy of a disagree.
2
The one size fits all recommendation isn't always the best fit for everyone. My drive to work is 2 miles. I go two or three days of driving around town before I would even get down to half full. Using an extra high daily charge level like 90% has no range benefit for me, and is just unnecessary faster degradation on the battery. Using 70% or 80% still gives me way more range than I need, has no range anxiety, and is a little better for the battery.
3
Here's a decent analogy. It's very like you are recommending everyone poke a hole in their skin with a needle every day. Many people would say, "Why? That hurts, and I can't see any need for it."
You respond: "It won't kill you. It's an insignificant injury, and you'll heal from it, and some people really need to do that to measure their blood sugar because they're diabetic."

See? How about the diabetic people who need to do that and have some benefit from it, get recommended to do that, but for people who don't have a benefit to doing it, get to avoid it?

1 - That's fair but that's not the solution you recommended that I quoted, which was the same thing I said people should do. Hey I'm just going by what happened to me, and what the forum has threads about. How to keep degredation at bay, lost range, etc. Often the recommendations are to charge to 60-70% every night to keep it healthier but do a cycle to bring your range back. Tesla makes all the cars so I'd think their single recommendation would fit, well, all their cars.
2 - I tend to agree regarding one size fits all in most life situations, but also tend to think Tesla knows it's tech better than anyone else. I think it's been shown that the degredation difference over 300,000 miles by charging to 90% vs 80% was insignificant. Do what you like, it's your car.
3 - I guess my response would be our cars aren't diabetic? A Tesla service person one said to me, "look at it this way, the battery is like a sponge and if you don't use a portion of it, it becomes useless." Maybe they're just blowing smoke and wanted me out of there, but again, they built it and I've seen my range come back after charging to 90% as they instructed. Your car, your call.

Enjoy your ride and have a great day!

 

[Rocky_H]

1 - That's fair but that's not the solution you recommended that I quoted, which was the same thing I said people should do. Hey I'm just going by what happened to me, and what the forum has threads about. How to keep degredation at bay, lost range, etc. Often the recommendations are to charge to 60-70% every night to keep it healthier but do a cycle to bring your range back. Tesla makes all the cars so I'd think their single recommendation would fit, well, all their cars.
2 - I tend to agree regarding one size fits all in most life situations, but also tend to think Tesla knows it's tech better than anyone else. I think it's been shown that the degredation difference over 300,000 miles by charging to 90% vs 80% was insignificant. Do what you like, it's your car.

You say you want to go by what Tesla recommends, so why are you arguing against Tesla's own battery experts?
Tesla battery expert recommends daily charging limit to optimize durability
Jeff Dahn is the most world-renowned expert in lithium ion batteries and works for Tesla now. His recommendation was at 70% for best battery health. And Musk had been recommending a use range around 30% to 80%. So they are all recommending lower than 90% for best use.

3 - I guess my response would be our cars aren't diabetic?

Missed the point a bit? You're recommending a slightly harmful thing for everyone because some people might need to do it.

A Tesla service person one said to me, "

Oh, the stories of what Tesla employees have told people. I was having a great argument with someone a few years ago, because a Tesla employee told him that every single one of the Superchargers were directly tied to solar panels only and had NO connection to the electric grid.

"look at it this way, the battery is like a sponge and if you don't use a portion of it, it becomes useless." Maybe they're just blowing smoke and wanted me out of there, but again, they built it and I've seen my range come back after charging to 90% as they instructed. Your car, your call.

There is a nugget of truth, but that is an entirely different issue. He is wrong that it can't be used, but he's referring to the software algorithms of the car becoming unable to detect the full extent of the battery if it is only used in that middle portion of the charge state. You can still get all of the energy out of it, though. And more fully exercising toward the high and low ends of the battery will keep the car able to "see" that energy and keep the energy estimations more accurate, but that is at the expense of working the battery harder and degrading it faster.

So yes, the more full cycle of running it very low and then refilling it up very high accomplishes something different to kind of true-up the estimation, and it appears to "gain" miles, but that's just an appearance thing and a warm fuzzy feeling for owners.

So those are two different charging recommendations for two different kinds of tasks for people to accomplish.

 

[dark cloud]

Then you were never poor. Or never an energy conservationist.

Plenty of people who drive ICE cars DO in fact pay a lot of attention and have been driving in ways that conserve energy for a long time. When gas prices suddenly increase, you will see more ICE drivers do things like condense shopping trips, use their a/c or heater less, driving slower and coasting into stops instead of slamming on the brakes last minute... and all those hybrid drivers? They don't have range anxiety but they often drive in ways that conserve energy.

Not true on either count. I was once a university student, lived on $10000 a year, and drove a 49 hp Rabbit diesel that would go 400 km for $15 in diesel. I now drive very efficiently 90% of the time. I have noticed very few people who drive as efficiently as I can. I am the type of driver who smooths traffic flow; all 3 cars in front of me are constantly accelerating and hitting their brakes in stop and go traffic but I don't hit the brakes once. It is an art to stay close enough for others not to cut you off, but far enough to use the least amount of pedal input. I would check tire pressures, change air filters, fluids, and spark plugs regularly for not only maximum efficiency but performance (the other 10% of my driving)

I also am the person who bought a high efficiency furnace in my house to go from 85% to 98% efficiency, knowing that it will take about 15 years to get to the break even point. I am considering solar with an even longer payback timeline.

When I know I cannot drive the vehicle any more efficiently there is no point to monitor it. If I wanted better efficiency I would have to buy a vehicle that would give better efficiency; i.e.: smaller. Obviously people on this forum are not after the utmost efficiency, they are willing to sacrifice some of that for comfort and luxury or they would have not bought a model S.

The point I was attempting to make is more people are analyzing their electric car battery range to the km/mile, whereas I am pretty sure when they had gas cars they didn't calculate their efficiency in L/100km or MPG every time they filled up, because they didn't have the tech which would enable them to easily do this.

I am pretty sure the purist energy conservationist doesn't drive at all.

 

[Eevee]

The tech to do real-time MPG in ICE and hybrid cars has been around awhile. I remember my 2000 Honda Insight had it and I'm pretty sure most hybrids have it. Now I see lots of ICE that have it. And there are aftermarket mpg gauges people can buy. And people do buy them. Not everyone cares about it, but it's not like no one cares.

My point was simply that it's NOT only EV owners who do things like turn the a/c off to increase efficiency.