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50% battery left, 75D, only 30.5 kWh used

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I've heard elsewhere that the RM/SoC indication is highly inaccurate in the mid-ranges, but much more accurate when the battery is full or nearly discharged. Now I have some data point showing how far off it can be. If 72.6 kWhr is usable, and 30.5 is reported 'used' (which I believe is an accurate accounting of watts in and out during driving), then car thinks there is 36.3 in the 'tank' when in reality, there is 42.1 kWhr (42.1+30.5 = 72.6 usable kWhr).
 
I've heard elsewhere that the RM/SoC indication is highly inaccurate in the mid-ranges, but much more accurate when the battery is full or nearly discharged. Now I have some data point showing how far off it can be. If 72.6 kWhr is usable, and 30.5 is reported 'used' (which I believe is an accurate accounting of watts in and out during driving), then car thinks there is 36.3 in the 'tank' when in reality, there is 42.1 kWhr (42.1+30.5 = 72.6 usable kWhr).
 
the unlock of the 60 to 75 is not really worth it. Like others have said, you get roughly an additional 10KWh usable.

However if you understand how you would use that extra 10KWh, you would probably not ever use it and therefore would never ever unlock it.

The extra 10KWh is only useful at the beginning of a road trip each day assuming you have overnight charging to 100%. This equates to around maybe an extra 33 miles at the beginning of the day assuming around 300wh/mile energy consumption.

During a road trip, no one really stays extra 30 - 45 minutes at a supercharging station to charge from 80% to 100% before leaving for the next supercharging stations. Most of the time you would probably stop charging at 85% to 90% if you really need it to make to the next one. Therefore you would never see the the benefit of the extra 10KWh during road trips charging.

I have to reiterate the cost benefit of the 75KWh upgrade. It is really there to make tesla some money and is in very few ways useful to the consumer. If the upgrade was $500, then it might be worth it. But at $2000, it's totally not worth the extra 33 miles occasionally during road trips at the beginning of the day each day of the road trip.
It's worth it for me because it lets me skip supercharging all together on the vast majority of the longer trips I take.
 
During a road trip, no one really stays extra 30 - 45 minutes at a supercharging station to charge from 80% to 100% before leaving for the next supercharging stations.
Easily worth it to us. We've done a number of cross-country trips and while most charges don't need to be above 80% or even 70%, there are some stretches that have required 90-100% charge. So yes, we have waited around for full or close to it top-up on several occasions. Fortunately these are almost all during lunch or dinner and when they've been otherwise we've had a good coffee place to go. The exception to the latter was Nashville (charging to make Birmingham) that had no place to hang out unless we wanted to eat a mid afternoon meal.

Then there's the skip a charger stop issue where having a few extra electrons available and waiting 5 or 10 minutes for them allows bypassing a stop. That said, I generally don't mind the stops and often welcome them as getting out and walking around a bit makes me feel much better and more awake while driving but sometimes skipping can still be worth it even for me.
 
I posted this in another thread - Tesla Motors: PLEASE stop lying about specifications (60 to 75 upgrade). It's very similar to the datapoints you've observed. No real resolution though from the discussion there.

Using trip meters in my X60D does not seem to jive with that. I charge to 100%(200 miles):
When I have 150 miles remaining range(75% battery remaining), the trip meter tells me that I've used 14.1kWh.
When I have 100 miles remaining range(50% battery remaining), the trip meter tells me that I've used 28.2kWh.

Extrapolating, that seems to mean that when I hit 0 miles remaining range(0% battery remaining), I will have used 56.4kWh. That doesn't jive with the 62.5kWh number. I definitely don't think wk057 is wrong, just trying to figure out where the disconnect may between what the trip meter says that I've used vs. what the battery is capable of.
 
During a road trip, no one really stays extra 30 - 45 minutes at a supercharging station to charge from 80% to 100% before leaving for the next supercharging stations.

When I read this statement I had to look at the location of the poster and sure enough "San Diego, CA". That explains it.

I've needed that extra from 80 to 100% a lot in the winter. Not only do you have to use heat in the winter, but the air is much denser so more energy is used just to drive through it, snow and rain affect range, plus the batteries are less efficient in the winter, even with Tesla's thermal management system.

To the OP in Washington DC -- you'll really appreciate that extra range in the winter. If you lived in California, perhaps it wouldn't make much of a difference, but range is king in my view, and the more the better, especially for colder climates.
 
I posted this in another thread - Tesla Motors: PLEASE stop lying about specifications (60 to 75 upgrade). It's very similar to the datapoints you've observed. No real resolution though from the discussion there.

Using trip meters in my X60D does not seem to jive with that. I charge to 100%(200 miles):
When I have 150 miles remaining range(75% battery remaining), the trip meter tells me that I've used 14.1kWh.
When I have 100 miles remaining range(50% battery remaining), the trip meter tells me that I've used 28.2kWh.

Extrapolating, that seems to mean that when I hit 0 miles remaining range(0% battery remaining), I will have used 56.4kWh. That doesn't jive with the 62.5kWh number. I definitely don't think wk057 is wrong, just trying to figure out where the disconnect may between what the trip meter says that I've used vs. what the battery is capable of.

I did this experiment almost 4 years ago with my old 60 and eventually got the answer - the reported used KWh do not include a few things, like vampire drain while parked and HVAC. In my experiment, there was an average 1.8KW draw that was unaccounted for, which would be consistent with HVAC. Here are a couple of graphs from those experiments (I had a GoPro setup snapping pictures of the dash stats every 2s). The first graph shows green line, which is what the rated range remaining should be if the car only used what it accounted for in the used energy, the red line shows the actual range remaining showing.
Observed_vs_Expected_Range.png

the second graph shows the total unaccounted for energy, which averages to 1.8KW draw.
Lost_Energy.png
 
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I did this experiment almost 4 years ago with my old 60 and eventually got the answer - the reported used KWh do not include a few things, like vampire drain while parked and HVAC. In my experiment, there was an average 1.8KW draw that was unaccounted for, which would be consistent with HVAC. Here are a couple of graphs from those experiments (I had a GoPro setup snapping pictures of the dash stats every 2s). The first graph shows green line, which is what the rated range remaining should be if the car only used what it accounted for in the used energy, the red line shows the actual range remaining showing.
View attachment 231031
the second graph shows the total unaccounted for energy, which averages to 1.8KW draw.
View attachment 231032

Thanks for all the replies- I think this last post might clinch the answer. The percent battery left is an estimate, and the kWh used is only those used for driving, not HVAC etc. add those two together and the % and kWh used do not always add up as one would expect, but they are usually close! Got it!