75kwh/259miles = ~290 wh/mi
He calculated about his battery is now 50kwh/290 wh/mi would be ~172 miles of rated range
As others pointed out though he probably forgot idle power and vampire drain
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Possible 35% battery degradation after 57k miles?
- Thread starter 2018_TS_S_P75D
- Start date
He calculated about his battery is now 50kwh/290 wh/mi would be ~172 miles of rated range
As others pointed out though he probably forgot idle power and vampire drain
New data with no Sentry or other "vampires", headlights off, AC on:
- 26 kWh corresponds to 47% battery drop (80% -> 33%) => max charge = 26 / 47 * 100 = 55kWh == 73% of new battery (75kWh)... is 27% capacity drop over 57k miles normal and expected !?
- unrelated: 408 Wh / mile average over 65 miles round trip with little traffic - not sure where all this energy goes
- 26 kWh corresponds to 47% battery drop (80% -> 33%) => max charge = 26 / 47 * 100 = 55kWh == 73% of new battery (75kWh)... is 27% capacity drop over 57k miles normal and expected !?
- unrelated: 408 Wh / mile average over 65 miles round trip with little traffic - not sure where all this energy goes
Speed, wind, temperature, elevation change?
You could try your trip in a better route planner and see what it gets? (ABRP)
ucmndd
Well-Known Member
It will be difficult to help you further if you don’t answer the questions you’ve been asked.
What does your car show for rated range when charged to 100%?
Averaging 400+ wh/mi is not “unrelated”, no matter how you slice or dice it. That’s not normal. Full stop. It’s related to whatever you’re experiencing.
What does your car show for rated range when charged to 100%?
Averaging 400+ wh/mi is not “unrelated”, no matter how you slice or dice it. That’s not normal. Full stop. It’s related to whatever you’re experiencing.
I thought he answered 225 for 100%
Also when calculating your battery capacity the latest drive efficiency is basically an independent variable
This does appear to be a round trip would like to know the deets of each way
ucmndd
Well-Known Member
You’re right, my bad.
So again, we have a consumption problem.
OP’s battery has degraded about 13% from new (which again, is pretty normal for this vintage battery/car - I own one). Meaning they’ve got about 63 kWh available for propulsion at 100% charge.
They’re reporting 408wh/mi over 65 miles, for 26.5 kWh. 26.5kwh is 42% of a ~63kwh battery.
OP is reporting a 47% drop instead of 42%, so we’ve got a delta of 5%. That’s frankly in the margin of error without further details to explore about the trip itself and what the car is doing while it’s sitting all day during the presumed idle period.
If I were OP the next thing I’d do is charge the battery to a real 100% and do the same trip to rule out any BMS drifting or inaccurate range estimates that are common issues with cars never actually charged to 100%.
But the real bottom line here: 400+ wh/mi is insane unless this trip has significant undisclosed variables that OP is not providing. That is NOT a typical efficiency for any “normal” trip in a 75D.
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FlyF4
Son of a MX
yes, agree exactly. And driving in Colorado in the winter doesn't help the consumption.
Yeah maybe he has cabin overheat protection on or something.. that's why I thought just the trips would be helpful
For reference.. I averaged 286 wh/mi over 150k miles in my 2012 P85 RWD and averaging about 275 wh/mi over 40k in my 2021 MYLR
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Sentry off, cabin overheat protection off, headlights off, AC on; drop after 10 hours on standby - 0%
Better route planning does not exist.
The round trip includes probably 300' elevation change... energy was compensated as we are talking about a round trip.
Return trip was 33 miles, took 36 min and avg energy was 414Wh / mi (I live on a hill) -> avg return speed - 55 miles / hr ; the trip includes both freeway and city streets, mostly freeway
Wind... whatever was in the SF Bay area yesterday; temperature 80 - 90 deg F
All these variable have to do with avg energy but not with battery health
As apparently only 72.5kWh are available when new, redoing the math shows me 76% battery availability at full charge. I am not seeing how that can be normal on a 4 years car with 75k miles as "Tesla has released a rare update on the battery degradation in its electric cars. The automaker claims its batteries only lose about 12% of capacity after 200,000 miles." (source Tesla gives update on battery degradation: only 12% after 200,000 miles).
At 80% full, the car estimates 181 rated miles and 226 ideal miles (that comes to 226 rated and 283 ideal miles!!! at 100% charged).
Better route planning does not exist.
The round trip includes probably 300' elevation change... energy was compensated as we are talking about a round trip.
Return trip was 33 miles, took 36 min and avg energy was 414Wh / mi (I live on a hill) -> avg return speed - 55 miles / hr ; the trip includes both freeway and city streets, mostly freeway
Wind... whatever was in the SF Bay area yesterday; temperature 80 - 90 deg F
All these variable have to do with avg energy but not with battery health
As apparently only 72.5kWh are available when new, redoing the math shows me 76% battery availability at full charge. I am not seeing how that can be normal on a 4 years car with 75k miles as "Tesla has released a rare update on the battery degradation in its electric cars. The automaker claims its batteries only lose about 12% of capacity after 200,000 miles." (source Tesla gives update on battery degradation: only 12% after 200,000 miles).
At 80% full, the car estimates 181 rated miles and 226 ideal miles (that comes to 226 rated and 283 ideal miles!!! at 100% charged).
you might have had a previous owner that abused the battery - maybe just left it at 100% state of charge for months or something..
the consumption is definitely a problem as well, though... maybe the alignment is way off or tire pressure? i'd certainly make a service appointment to communicate your issues.... you should be able to get ~160 real world miles but i'd still charge everyday if i were you anyway cause you don't wanna be going 100% to 0% every other day
you may want to install teslamate or try teslafi (14 day free trial) or maybe even just register at abetterrouteplanner.com to get more insight and details into your vehicle
honestly i have a feeling your wife is cruising at 80mph to keep up with traffic ... 36 minutes to go 33 miles with city streets likely means someone is doing well over 60 on the highway
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Yeah, I don't think this is about the battery, but is more about how the car is driving somehow. I would think there is something putting extra resistance on this. My first guesses would be bad alignment or a stuck brake caliper or maybe tire pressure.
As other people have said your primary issue is not one of degradation... One of the first things I would check is to make sure the brakes aren't dragging. (You can check to see how warm the rotors are after a trip where you try to only use regen. But don't just go touching them in case they are really hot.)
ucmndd
Well-Known Member
For the last time:
Charge your car to 100% and repeat your trip. Maybe do this a couple times.
Find out why your car is consuming 400+wh/mi. It is not normal. It is relevant.
If you want to keep pounding the capacity drum, invest in something like ScanMyTesla and get real numbers from the BMS instead of bar napkin trip computer math.
vcor
Tech Specialist
As others pointed out, it doesn't appear to be a battery issue, but a consumption issue. A few possibilities somewhat in order of likelihood:
1) The HVAC compressor is running at maximum speed due to an HVAC problem like low refrigerant (this makes a lot of noise outside the car).
2) Brakes are causing undesired friction (as others pointed out).
3) A wheel bearing is failing causing major friction (usually also makes a lot of noise).
4) The coolant pumps are running continuously at maximum power when they are not really needed (sensor problem?)
5) One of the resistive heaters (Cabin or PTC) has failed and is on all the time (not sure I've ever heard of this). The HVAC has to run at maximum to compensate.
6) One of the two propulsion motors has some kind of failure that is causing unusual frictional losses or excessive electrical load.
Lastly, new owners are not used to the massive power available and often "gun it" coming off every stop. While fun, it also consumes a lot of power. Other EVs with very little power as compared with the Model S can't do this and don't offer the same level of fun. I don't think this is the case, as normal freeway driving doesn't lend itself to hard acceleration as much, but it is possible. The energy graph would show if there are a lot of high-energy peaks for the last 30 miles.
Troubleshooting this remotely is difficult, especially as the poster is not the driver. The best answer is to take it to Tesla service and explain that you're getting very little range, and something is consuming too much power while driving. The 400 W/mi is the key indicator to explain. Don't even bother to talk about the battery. It doesn't seem to have anything to do with the issue.
1) The HVAC compressor is running at maximum speed due to an HVAC problem like low refrigerant (this makes a lot of noise outside the car).
2) Brakes are causing undesired friction (as others pointed out).
3) A wheel bearing is failing causing major friction (usually also makes a lot of noise).
4) The coolant pumps are running continuously at maximum power when they are not really needed (sensor problem?)
5) One of the resistive heaters (Cabin or PTC) has failed and is on all the time (not sure I've ever heard of this). The HVAC has to run at maximum to compensate.
6) One of the two propulsion motors has some kind of failure that is causing unusual frictional losses or excessive electrical load.
Lastly, new owners are not used to the massive power available and often "gun it" coming off every stop. While fun, it also consumes a lot of power. Other EVs with very little power as compared with the Model S can't do this and don't offer the same level of fun. I don't think this is the case, as normal freeway driving doesn't lend itself to hard acceleration as much, but it is possible. The energy graph would show if there are a lot of high-energy peaks for the last 30 miles.
Troubleshooting this remotely is difficult, especially as the poster is not the driver. The best answer is to take it to Tesla service and explain that you're getting very little range, and something is consuming too much power while driving. The 400 W/mi is the key indicator to explain. Don't even bother to talk about the battery. It doesn't seem to have anything to do with the issue.
go sign up for teslafi and let us know the deets... it will give you more detail as to where the energy is going
Ugh. That's frustrating. There can certainly be problems with the car that don't show up as software alerts--like incorrect wheel alignment. That's rude of them to just cancel it without discussing.
First, there is one experiment you could try to eliminate a couple of variables. To remove HVAC issues from the issue, hold your finger on that temperature number for a couple of seconds until the HVAC system actually turns OFF. Like all the way OFF. And then do some driving like that. That will remove the possibility of things in that system, like runaway A/C or conflicting heating and cooling from different parts of the system, etc.
So if that shows a significant change or not will be helpful to see if that's where the high energy consumption is coming from or if it's more likely from somewhere in the wheel/tire/motor side of things.
But after trying that to collect that piece of data, I would have to go back to continually re-opening the service requests to force them to look at it. You can be just as persistent re-opening cases as they can in closing them.
Even that shouldn't be necessary. Don't the cars have a screen somewhere that shows a detailed allocation of the energy usage, or is that only on the much newer cars?
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