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2021 LR dropped 82% for 47 kWh? [sentry mode on]

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I've owned the car for more than a year and it is the first time charging it to 100% and driving a long trip. I thought it would make it a round trip but the battery dropped to 18% after a single trip. But the number doesn't add up. It says it used 47 kWh but the battery dropped 82%. This should be an 82 kWh battery with 76 kWh usable capacity as I read. The car was produced in the US. Can anyone explain?

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...explain?
Tesla used to proudly show the kWh badge for its cars "40", "60", "75", "90", and "100..." but people kept complaining that their maths prove that Tesla has cheated them, so Tesla has stopped advertising the kWh.

The more accurate way is to charge your car to 100% and compare the current range with the original range and as long as it's within 70% capacity in the original calculated range, that's the warranty.

People keep forgetting the inefficiency factors, such as sentry mode, HVAC... that produce no range at all (all those lost kWh are not recorded in the maths).
 
I won't expect the numbers to be accurate. But I think mine is way too off. 242 km took 82% of the battery on a sunny day at an average speed of less than 120 km/h on the freeway. I don't think the energy expense when not driving will take 10 kWh unless something is wrong.
 
Have you started driving immediately after charging to 100% ?
Did you see 100% displayed on the car and had it finished charging?
Did you drive 242km straight without stops to look at the trip meter immediately after and see 47kWh?

EDIT: forget about how sunny it is etc, it doesn't matter. 242km at 195wh/km is 47.190kWh. The way you drove, the terrain, temperature etc consumed on average 195wh/km. There is nothing else to worry about here.
 
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ah, 3 days after. Then your car could have spent 3 days worth of whatever drains the battery. Did you have sentry on? Did you consult your mobile app often? A car that's awake consumes 200-250w constantly. 3 days means between 14.4-18kWh if the car was awake all the time. If you add that to your 47kWh, you'll get to your 82% drop total.

The drive itself only consumed 47kWh, or about 62% if you assume you have 76kWh "usable over 0%".
 
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If the battery is drained during not driving, doesn't it show a % drop? Say if it drops 5 kWh during the night, I should see a 6% drop next morning, but that didn't happen

Did you use sentry mode when you parked wherever you were going on your trip?

Note that, there has not been a single time I can think of, in all of these "range" posts (and we have a thread with 250+ pages of posts.. not 250 posts but 250+ pages of posts) that "My car consumption was higher than I expected" = "an issue with the battery".
 
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That's what I just explained higher up. Sentry doesn't consume anything by itself but it keeps the whole car awake running the cameras computer etc to do its job. When the car is awake, it consumes 200-250w. That means that in 4-5h 1kWh is consumed. Count it for 3 days and you get 14-18kWh as I indicated.
Yes, your battery SOC did drop during that time. You probably arrived at your destination at 36% and you left at 18% SOC.

EDIT: In comparison, when asleep the car only consumes 20w or possibly even less. If you count it with 20w, you would have only used 1.4kWh, just a couple percent SOC.
 
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242 km took 82% of the battery on a sunny day at an average speed of less than 120 km/h on the freeway.

Sounds like you have this figured out now.

Anyway, 47kWh, assuming (note no need to assume; this is knowable from your 100% charge km/mi displayed) you have about 78kWh of capacity left (74.5kWh usable), is:

47kWh/74.5kWh = ~63%.

So that‘s roughly what you would have seen. The rest (~19%) was used while in park.

It all basically works perfectly nearly always and everything is perfectly accounted for.

The new software will be helpful but not for helping people understand this. Now we just need a version of the software that tabulates the losses while in park! (Sometimes they are positive losses, sometimes they are negative losses (gain in miles/km/% after parking), but overall of course they eventually add up to net losses.)
 
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The updated Energy app delivered in 2022.36.x neatly tabulates all energy usage. Works a peach!
Does it track use in Park (I don’t have it)? That was what I thought would be more difficult to implement (specifically sleep mode losses (and gains)), though definitely possible since it is possible to do by hand.

Also can you post a screenshot? Too lazy to look it up. Good to see Tesla is finally getting this, 6 years after my Spark EV.
 
I havent been anywhere since yesterday morning, but here it is in my car:


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Thanks. Awesome, that’s really good - it does track use in Park (somehow I had got the impression it did not). Finally maybe no more questions on this. There will of course still be questions, lol.

I’m curious how negative usage will be tabulated, or whether they will set a floor of 0 on the display.

Still no pie chart like on the Spark EV. Much more granular detail though. 2016 pie chart technology. Maybe by 2026.
 
Thanks. Awesome, that’s really good - it does track use in Park (somehow I had got the impression it did not). Finally maybe no more questions on this. There will of course still be questions, lol.

I’m curious how negative usage will be tabulated, or whether they will set a floor of 0 on the display.

This strikes me 100% as something tesla would have implemented to cut down on service requests. What I mean is, I do not work for tesla, but based on our interactions here, I am like 99% positive that Teslas metrics show the same thing that is shown here, which is, the #1 service request (thread topic) is something around "I dont get the range I expect from my battery" or "there is something wrong with my car, I drove XXX distance but the car says I used XXX+20% battery, My car is broken, right?"

Implementing something like this that they can point to and say "consumption is shown in the car, please check that" (when canceling their service request) is simply a matter of trying to cut down on these requests, with the side effect of giving users more information (which is good, I agree).