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High power consumption at "start up"?

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I notice that right after getting in my car and beginning to drive, the power consumption average (on the trip screen) is very high, upwards of 400-600. This is represented by a high spike on the energy graph as well.
After a mile or so, the average declines and the energy consumption starts to level off to a more reasonable level, on the graph also.
Is it normal for there to be an energy spike when getting in the car and driving after it has been sitting a while? I didn't know if this was some type of startup surge or something? (happens regardless of AC running, but it has been in the 90s here lately).
 
When you first start moving the instantaneous energy used could be between 30kW and 100kW. When you've only driven 1/4 of a mile the Wh/mi number will be wildly inflated.The displayed energy consumption could appear to be 900Wh/mi. Until the Tesla software has more data points and you have driven at least 1 mile or more the energy usage per mile is inflated by several times the actual value.
 
I notice that right after getting in my car and beginning to drive, the power consumption average (on the trip screen) is very high, upwards of 400-600. This is represented by a high spike on the energy graph as well.
After a mile or so, the average declines and the energy consumption starts to level off to a more reasonable level, on the graph also.
Is it normal for there to be an energy spike when getting in the car and driving after it has been sitting a while? I didn't know if this was some type of startup surge or something? (happens regardless of AC running, but it has been in the 90s here lately).
Yes this is normal and you see this in gas cars as well. It takes a few miles to get things warmed up and lined out.
 
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Is it normal for there to be an energy spike when getting in the car and driving after it has been sitting a while?
Yes.
The energy usage when first starting to drive is not accurate. The Tesla vehicle's energy usage is based on data samples. With so few samples, initially, the energy usage is not accurate. Only after several miles of driving does the software have enough data to begin to provide an accurate reading.
Uhh, well, that is part of it, but it's also more real than that. Energy usage actually does stay high for the first few minutes anyway. If it's your first drive in the morning after the car has sat overnight, the battery is cool. Even if you don't think it's all that warm yet, the battery is probably colder, and the car may warm that a little bit when you first start driving.
 
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When you first start moving the instantaneous energy used could be between 30kW and 100kW. When you've only driven 1/4 of a mile the Wh/mi number will be wildly inflated.The displayed energy consumption could appear to be 900Wh/mi. Until the Tesla software has more data points and you have driven at least 1 mile or more the energy usage per mile is inflated by several times the actual value.
Yes.

Uhh, well, that is part of it, but it's also more real than that. Energy usage actually does stay high for the first few minutes anyway. If it's your first drive in the morning after the car has sat overnight, the battery is cool. Even if you don't think it's all that warm yet, the battery is probably colder, and the car may warm that a little bit when you first start driving.
I always precondition before driving; In summer the overnight temperature in my garage and everything in it including my Model Y is typically ~84F.
 
When you first start moving the instantaneous energy used could be between 30kW and 100kW. When you've only driven 1/4 of a mile the Wh/mi number will be wildly inflated.The displayed energy consumption could appear to be 900Wh/mi. Until the Tesla software has more data points and you have driven at least 1 mile or more the energy usage per mile is inflated by several times the actual value.
It's certainly not 1 mile. It does the calculations per distance on some pretty small increments that are about a tenth I think, or less.
But you're still not quite getting it. I know what you are talking about, with measurement error, and that is happening, but isn't all of it. You can see it directly in the instantaneous usage, which can stay very high, like 900 Wh/mi for a few minutes continuously--more so and for longer in the Winter, but it can do it for a short time in summer too.
I always precondition before driving; In summer the overnight temperature in my garage and everything in it including my Model Y is typically ~84F.
OK, that's what you do. I'm trying to give an answer to @Wolfpacker83 and more generally to other people who may not do extensive preconditioning or have garage conditions that maybe get a bit cooler overnight. The car may do a bit of heating when you first start driving for a few minutes. I'm pointing out that this can happen, and can really be an extra few hundred Wh/mi above what it takes to drive for a few minutes.
 
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Today I preconditioned for 5 minutes, drove 4 miles. (The temperature was 80F.) I parked for an hour and charged and then drove home. For the return trip, since charging resets the Since Last Charge trip calculator, my Model Y's reported Wh/mi for the first 1.5 miles started out high ~400Wh/mi and kept dropping. The Since Last Charge energy number was 254 Wh/mi by the time I arrived home. (The Wh/mi number did bounce around a little as i drove the route home pretty much staying within the speed limit.) This is my daily A.M. routine, most days, this happens every time. Tesla could decide to not display the Wh/mi for the first mile of driving and I would be fine with it.

I will try the return trip, HVAC fan only, to see if this makes a difference.
 
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This afternoon I preconditioned my Model Y for ~10 minutes. The cabin temperature was 94F when I started preconditioning and ~70F when I started driving. I reset the trip computer before starting to drive and turned off the AC. For the first 0.2 miles there was no readout. Then 968 Wh/mi; after another tenth of a mile the reading dropped to 400 Wh/mi and continued to drop as I drove. By 0.7 miles the Wh/mi was ~300 Wh/mi and by 1.0 mile it was ~220 Wh/mi. This was mostly down hill, at speeds under 40 MPH, with one traffic signal (where I did stop.) On the return trip, about an hour later, I preconditioned and this time I left the AC running as I started to drive home. The initial Wh/mi number was greater than 700 Wh/mi, by the time I returned home the Wh/mi was reading 280 Wh/mi (this was with the AC running.) In conclusion I observed that the Wh/mi readout can be 2X or 3X greater than the actual value for the first half mile. By one mile the readout is consistent, the Model Y provides a more accurate reading.
 
It’s not an inaccurate reading. It’s completely accurate. But you’re dividing a decent power consumption by a very small mileage reading. Imagine you started your ICE car, and let it idle two hours and burned a gallon of fuel. You then drove the car one mile. Your MPG would be 1 MPG. After 2 it would be 2, then 3 for 3, etc, until you reasonably recovered. Same with the car. The HVAC load isn’t as substantial as driving so Once the miles dividing the consumption is more logical and it corrects for a “normal” reading.
but I’ve taken very short drives, and it’s never corrected itself. Would read 450 wH/ mile even though I drove very slowly. I’m just not driving far enough. For instance from my house to my kid’s school. In the winter, that 1.1 mile drive will often report as 500 Wh/mile even though my max speed is about 35 and im doing a lot of regen.
 
Enev without HVAC the reading is high at the beginning and that's perfectly normal and accurate.

When I pull out of my driveway and accelerate to 80 kph fast I get readings of up to ~1000 Wh/km. The reason it goes down shortly after is not that it gets more accurate over time. Truth is, I just accelerated about 1,950 kg to 80 kph in a matter of a few seconds in a very short distance. If I immediately stopped the car afterwards with minimal regen, then this would be the accurate consumption.
But that's not how it goes. As I keep going at a constant 80 kph the instant consumption is low, thus lowering the average. After about 4 km I slow down to a standstill using only regen which lowers the average even further to a "normal" number.

The initial high consumption only ocurs because the meter starts counting when you put the car in gear. At that point, all you can do is accelerate and this naturally takes a lot of energy and that's the reason why the displayed number is high at the beginning. Yes, it goes down fairly quickly, but that doesn't mean that the initial reading was wrong, it's just what you get if you bring a heavy piece of metal up to speed.

Obviously it gets even worse with the HVAC running.
 
The measure is Wh/mi. Until you have driven 1 mile the readout should remain blank. The instantaneous consumption, i.e. 968 Wh/mi may be accurate but it is confusing to the driver and does not provide any useful information. You can't interpret the result, respond with an appropriate course of action while the energy consumption readout is in free fall.