Where all my charge go? Some statistic and math questions for Tesla experts and nerds. Where all charge disappearing?

[abalexab]

A question for those who understand batteries and know where and how the car uses them. I'm trying to keep track of my battery consumption. And here is the latest data I have measured. Last time I charged the car at 100% (90 kW battery and yes - I know that charging at 100% is bad for me). After 6 days came to supercharger with 20% charge. All the data is shown in the photo. First pic before final charge and second after final charge. In 6 days the car drove 136 miles at an average consumption of 344 w/ml and used 46.8 kWh. That being said, I charged it again at 100% and the car took the charger 58 kWh.
I have the following questions:

1. Where did the 11 kW difference go? I'm in NYC. Temperature is 60-76F these days. Air conditioning has been on for maybe 2 hours. The rest of the time the climate is either off or fan only on. Total travel time was aprox 7 hours (traffic, traffic lights ect). For a natural discharge is also a bit much.
2. It turns out that at this consumption car will only drive 170 ml instead of 252 (I understand - it's city mileage, but the battery consumption is quite economical).
3. 58 kW charging from 20 to 100% does not give a total battery capacity of 90 kW. Does this mean that the battery capacity has dropped a lot or am I missing something?

Please do not share tips like "need to change the battery". All advice based on personal experience and knowledge would be welcome.
My car model X 90D 2016.

 

[mxnym]

If you find the right old threads, I think you'll learn that a 90 seldom, if ever had a 90 kW battery to begin with. Beyond that, you should certainly also see discussion about how a significant amount of battery degradation occurs in the first year or two. The year really doesn't tell everything there is to be told on a 2016. Is it AP1 or AP2? If AP2, does it have FSD and was it upgraded to AP3 accordingly? Is it MCU1 or has it been upgraded to MCU2? MCU1 has an option to keep mobile on while sleeping which would use more battery. An aging 12V would require the HV to be activated to recharge it more often while parked. If it's new and/or upgraded enough to have everything necessary for sentry mode, that can drain a lot of battery. Cabin overheat protection uses the A/C if you don't have the option to set it to fan only or if that option is not set. In reality, for 6 days, you're losing less than 2kW per day, and as there is definitely always some power draw, per day is a better way to look at it, but you might be able to improve it by adjusting some settings. Your battery is probably fine.

 

[abalexab]

If you find the right old threads, I think you'll learn that a 90 seldom, if ever had a 90 kW battery to begin with. Beyond that, you should certainly also see discussion about how a significant amount of battery degradation occurs in the first year or two. The year really doesn't tell everything there is to be told on a 2016. Is it AP1 or AP2? If AP2, does it have FSD and was it upgraded to AP3 accordingly? Is it MCU1 or has it been upgraded to MCU2? MCU1 has an option to keep mobile on while sleeping which would use more battery. An aging 12V would require the HV to be activated to recharge it more often while parked. If it's new and/or upgraded enough to have everything necessary for sentry mode, that can drain a lot of battery. Cabin overheat protection uses the A/C if you don't have the option to set it to fan only or if that option is not set. In reality, for 6 days, you're losing less than 2kW per day, and as there is definitely always some power draw, per day is a better way to look at it, but you might be able to improve it by adjusting some settings. Your battery is probably fine.

I did MCU upgrade and have MCU2. Autopilot 1.0. Because I have only 2 cameras - no century mode. Car not running overheat protection. I install EEVEE app which tracing drain when parked. Drain is normal and less than 1% per day. It’s showing “less than 1%“ and describing it as “minus 1 mile”. On some days minus 2-3 mils which is making no difference. Nothing above explaining why difference between both reading so significant. Also if 12V battery taking charge too this is not 12 kW for 6 days. One thing - my EEVEE app showing I took on supercharger 63 kW not 58. This probably can be expanded by heating battery but people in another article trying to convince me Tesla app and car itself have more accurate data than EEVEE. User who told me this have at home dedicated electric meter and both reading always the same. I’m not sure if this apply on supercharger as well. EEVEE ALWAYS (!!!) showing consumed charge more than car itself.

 

[Rocky_H]

Where did the 11 kW difference go?

Here is where it went:

After 6 days

That energy display you posted a picture of fools a lot of people. It's not accumulating data 24 hours a day. It only tracks energy usage while the car is in Drive gear. So any other energy usage during idle time, overnight, while the car is sleeping, etc. is being used, but is not being added to that display. So over the course of 6 days that can be a significant amount.

 

[abalexab]

Here is where it went:

That energy display you posted a picture of fools a lot of people. It's not accumulating data 24 hours a day. It only tracks energy usage while the car is in Drive gear. So any other energy usage during idle time, overnight, while the car is sleeping, etc. is being used, but is not being added to that display. So over the course of 6 days that can be a significant amount.

I agree, but not 12 kW with 60 F outside!!! I used EEVEE which register drain in miles and percentage and this number was not significant Probably 2-3% from entire 90 kW battery. It’s definitely not 12 kW.

 

[gaswalla]

On the Tesla App, go to Service, and click on Vehicle Range. After it performs the analysis, it will tell you where your range went (tab “Park”)

 

[abalexab]

On the Tesla App, go to Service, and click on Vehicle Range. After it performs the analysis, it will tell you where your range went (tab “Park”)

Thank you for advice. I know about this option but unfortunately this analysis showing only data for last trip. My EEVEE app giving me same analysis but with more details plus entire history. This data does not explaining where 12 kW disappear.

 

[abalexab]

If you find the right old threads, I think you'll learn that a 90 seldom, if ever had a 90 kW battery to begin with. Beyond that, you should certainly also see discussion about how a significant amount of battery degradation occurs in the first year or two. The year really doesn't tell everything there is to be told on a 2016. Is it AP1 or AP2? If AP2, does it have FSD and was it upgraded to AP3 accordingly? Is it MCU1 or has it been upgraded to MCU2? MCU1 has an option to keep mobile on while sleeping which would use more battery. An aging 12V would require the HV to be activated to recharge it more often while parked. If it's new and/or upgraded enough to have everything necessary for sentry mode, that can drain a lot of battery. Cabin overheat protection uses the A/C if you don't have the option to set it to fan only or if that option is not set. In reality, for 6 days, you're losing less than 2kW per day, and as there is definitely always some power draw, per day is a better way to look at it, but you might be able to improve it by adjusting some settings. Your battery is probably fine.

Thanks again for your reply. Would you point me to more info about 90 seldom please? I run search and didn’t find any threads about it. Thanks you in advance

 

[mxnym]

Thanks again for your reply. Would you point me to more info about 90 seldom please? I run search and didn’t find any threads about it. Thanks you in advance

I'm going off of memory because these discussions were so long ago, but here are a couple threads that might interest you:

X90D battery capacity question

My mid 2016 built X90D was indicating about 36 KWh used at 50% down from a max charge so I was concerned. As a test I ran it down for the first time to zero and did a max range charge to 100% and the dash indicated 73 KWh. Is this normal? I was expecting around 84 KWh. My email to Tesla...

teslamotorsclub.com

Tesla's 85 kWh rating needs an asterisk (up to 81 kWh, with up to ~77 kWh usable)

NOTE / PLEASE READ FIRST: 2016-02-11: Just adding an important note pointing out that there is a LOT of misinformation getting thrown around and perpetuated in the replies here on this thread. I have no control over what other people post/reply, and I can't waste time battling random people on...

teslamotorsclub.com

 

[brainhouston]

My 90D with 89k mi has 76kW usable left.. n 4kW is buffer i believe..
The "missing" kW got used over 6 days like others said
I can tell u for sure its not 1% per day lol
Do a test, leave the car parked for 6 days n see how many % u loose on the dash (not the app)
Also, when u Drive, Stop, Park, Drive... repeat... idle usage is higher then just parked for 6 days.

 

[Zeeshan Javaid]

What about battery percentage? Does it measure everything like HVAC and consumption when car is parked?

 

[DCGOO]

What about battery percentage? Does it measure everything like HVAC and consumption when car is parked?

Energy consumed while in Park is ignored. Including energy used for Sentry Mode and Cabin Overheat.

 

[Zeeshan Javaid]

Even on percentage ?

 

[Big Earl]

When talking about battery capacity, the unit is kWh (kilowatt hours), which is like fuel quantity. Instant power consumption (charging, driving) is measured in kW (kilowatts), like horsepower.

The battery in question here is a 90 kWh unit that probably has about 80 kWh usable when fully charged.

Regarding disappearing range/energy, you’ll want to check the usual suspects:

• Sentry mode
• 3rd party apps
• Excessive remote climate control use

 

[Tronguy]

Just became aware of this thread. I'm going to chime in with @Big Earl a bit with a bit more information.

First: Energy is a quantity, like a bucket holds water. The SI unit for energy is the Joule.

Second: Power is a rate, like how much water flows through a hose. The SI unit for power is the Watt, and the Watt is defined as 1 Joule/second.

That 100W lightbulb illuminating your hallway? Yep, it's using 100 Joules per second.

Power companies pay for, say, coal. By the kilogram (sticking with SI-sort-of units for the moment). If one burns 1 kg of coal, it liberates 30 MJ of heat, which can then be used to boil water into steam. Run the steam through a turbine, which turns a generator, which generates electrical energy. My understanding is that electrical power plants are about 90% efficient when doing this, so that's 27 MJ of electrical energy sent down the transmission line. There's more losses between the generator plant and a house, but let's ignore that for now.

As you might expect, power companies sell that electrical energy to consumers. For various historical reasons power companies (and everybody else) tends to measure energy in kW-hr, which is the amount of energy given by 1 kW over one hour. Since there's 3600 seconds in an hour, 1000W * 3600s = 3.6 MJ.

So, at my place, the power company charges about $0.18 per kW-hr; so, roughly, for that 1 kg of coal that the utility burned, they got back
27MJ*(kW-hr/3.6MJ)*($0.18/kW-hr) = $1.35 per kg. By which I conclude that coal is relatively cheap, since the utility has to pay for the coal, the plant, the salaries of all the workers, maintenance on the transmission lines, and so on. Not to mention dividends to the stock holders of the utilities.

In any case, energy capacity of the batteries in Teslas tend to be measured in kW-hr's, since that's kind of how the the money numbers flow.

So, this shows up in other places, too. The Malroney sticker on a BEV lists its EPA efficiency in kW-hr per 100 miles. So, my M3 has 25 kW-hr/100 miles; which, dividing, shows 250 W-hr/mile. Which is about right.

Thing is, the EPA numbers are when the car is being driven. For a gas car, if the car's not on, the gasoline stays in the tank. For a BEV, that's a case of "not so much". Things that use energy when the car's parked, in no particular order:

• Sentry mode. Those cameras and the computer behind them don't work for free.
• Continually checking on the car's status, by:
  • The app
  • Any third party tools
• Climate control, as in Overheat, camp mode, or what all.

Just so we're clear: The power consumption of the driving computer is something like 350W; the media computer is something less. But when they're on, well: That's 0.35kW-hr of energy used every hour, and, well, it adds up.

Sometimes people call this Vampire Drain. I guess because people don't like vampires or something. But, even with the car in sleep mode, it uses about a mile of range a day just to be ready in case somebody shows up with a key and wants in.

 

[abalexab]

Just became aware of this thread. I'm going to chime in with @Big Earl a bit with a bit more information.

First: Energy is a quantity, like a bucket holds water. The SI unit for energy is the Joule.

Second: Power is a rate, like how much water flows through a hose. The SI unit for power is the Watt, and the Watt is defined as 1 Joule/second.

That 100W lightbulb illuminating your hallway? Yep, it's using 100 Joules per second.

Power companies pay for, say, coal. By the kilogram (sticking with SI-sort-of units for the moment). If one burns 1 kg of coal, it liberates 30 MJ of heat, which can then be used to boil water into steam. Run the steam through a turbine, which turns a generator, which generates electrical energy. My understanding is that electrical power plants are about 90% efficient when doing this, so that's 27 MJ of electrical energy sent down the transmission line. There's more losses between the generator plant and a house, but let's ignore that for now.

As you might expect, power companies sell that electrical energy to consumers. For various historical reasons power companies (and everybody else) tends to measure energy in kW-hr, which is the amount of energy given by 1 kW over one hour. Since there's 3600 seconds in an hour, 1000W * 3600s = 3.6 MJ.

So, at my place, the power company charges about $0.18 per kW-hr; so, roughly, for that 1 kg of coal that the utility burned, they got back
27MJ*(kW-hr/3.6MJ)*($0.18/kW-hr) = $1.35 per kg. By which I conclude that coal is relatively cheap, since the utility has to pay for the coal, the plant, the salaries of all the workers, maintenance on the transmission lines, and so on. Not to mention dividends to the stock holders of the utilities.

In any case, energy capacity of the batteries in Teslas tend to be measured in kW-hr's, since that's kind of how the the money numbers flow.

So, this shows up in other places, too. The Malroney sticker on a BEV lists its EPA efficiency in kW-hr per 100 miles. So, my M3 has 25 kW-hr/100 miles; which, dividing, shows 250 W-hr/mile. Which is about right.

Thing is, the EPA numbers are when the car is being driven. For a gas car, if the car's not on, the gasoline stays in the tank. For a BEV, that's a case of "not so much". Things that use energy when the car's parked, in no particular order:

• Sentry mode. Those cameras and the computer behind them don't work for free.
• Continually checking on the car's status, by:
  • The app
  • Any third party tools
• Climate control, as in Overheat, camp mode, or what all.

Just so we're clear: The power consumption of the driving computer is something like 350W; the media computer is something less. But when they're on, well: That's 0.35kW-hr of energy used every hour, and, well, it adds up.

Sometimes people call this Vampire Drain. I guess because people don't like vampires or something. But, even with the car in sleep mode, it uses about a mile of range a day just to be ready in case somebody shows up with a key and wants in.

Mile a day is not bad. My MX 90D draining 3-5 ml per day. No extra usage. No overheat protection or century mode. 70 to 80 F outside (no battery warm up).