I'm a Tesla defender but I have to own up to this one

[green1]

According to the Tesla website (not sure if this is completely objective, but anyway) MS gets MPGE 138.5. So 2.5 gallons X 138.5 = 346. Actually the MS may have a lesser equivalent,

I thought the number we were working with was 89mpge?

 

[Ben W]

Please, don't go telling those kinds of incorrect things. We do NOT have access to the complete 85kwh of the battery for driving range. There are several kwh reserved at the bottom of the battery level (sometimes referred to as anti-bricking protection) that Tesla keeps us from accessing so we do not damage the battery packs. The car will shut down with those kwh of charge remaining to protect us from messing that up. So the rated value for the S85/P85 variants of the car is not 321. It's a little under 300. That has been confirmed by many people. I saw a guy here on the forums taking his highway wh/mile that he can usually get and multiplying it out by 85kwh, thinking he could drive all the way from Tremonton to Boise straight through, and I had to warn him that he was very likely going to come up short, because of not actually having 85kwh to work with.

I stand corrected, and have corrected my post above. Below is a schematic of how the total 85kWh is divided up.

EPA “Rated miles” are therefore somewhere around 306Wh/mi, and the “Rated miles” display on the dash ticks down at roughly 286Wh/mi to account for the 5kWh emergency buffer below “0 miles”.

 

[Rocky_H]

I stand corrected, and have corrected my post above. Below is a schematic of how the total 85kWh is divided up.

EPA “Rated miles” are therefore somewhere around 306Wh/mi, and the “Rated miles” display on the dash ticks down at roughly 286Wh/mi to account for the 5kWh emergency buffer below “0 miles”.

View attachment 85383

Yep, that is what I was referring to. I have seen that diagram and some discussion around it. I will clarify a bit, though, about that. That diagram is fairly old, and there has been a change in one of the firmware revisions a while back, maybe around 5.9, I think? There isn't the 5.1 kwh of "below zero" anymore. They had that early on to try to protect people from their own bad decisions/inexperience and avoid bad PR stories of people running out and getting stuck. So there used to be somewhere around 15-ish miles that people could go after the display read 0. Since that update, the below zero doesn't seem to be there. I went searching for this topic about a month ago on this forum and found several stories of people getting right to 0 or just a mile or two past it, and the car shutting down.

So the anti-bricking reserve is still there, but I think they moved that 5.1kwh up into the regular usable range, and people had better not count on going below 0 anymore.

 

[Ben W]

Yep, that is what I was referring to. I have seen that diagram and some discussion around it. I will clarify a bit, though, about that. That diagram is fairly old, and there has been a change in one of the firmware revisions a while back, maybe around 5.9, I think? There isn't the 5.1 kwh of "below zero" anymore. They had that early on to try to protect people from their own bad decisions/inexperience and avoid bad PR stories of people running out and getting stuck. So there used to be somewhere around 15-ish miles that people could go after the display read 0. Since that update, the below zero doesn't seem to be there. I went searching for this topic about a month ago on this forum and found several stories of people getting right to 0 or just a mile or two past it, and the car shutting down.

So the anti-bricking reserve is still there, but I think they moved that 5.1kwh up into the regular usable range, and people had better not count on going below 0 anymore.

Interesting. I’ll do some measurements on my drive today, and see how it looks with the latest firmware. Presumably Tesla found that very few people were ever driving the car down below zero, so the extra buffer wasn’t really useful.

The lowest I’ve ever gotten was down to 2 rated miles (a couple years ago), and in that case I calibrated my driving carefully to avoid reaching zero. It was a very long trip from the Harris Ranch Supercharger to the Folsom Supercharger, about 202 miles. The Manteca Supercharger now helps with that drive.

 

[AlMc]

Yes, I believe both comments are quite right. Also, one has to think about the future - batteries do lose capacity over time. My tendency is to keep a car that I like for a long time (typ. > 10 years), so the higher capacity would seem to be a necessity. Also, in the deep south, one has to use A/C a lot, and you have to set aside capacity for that as well.

In northern climates when heating during the winter months you can just about cut your rated range by 30-50% depending on the ambient temp.

 

[McMuggets]

Tesla's new tool on their website lets you adjust speed of driving plus ambient temp and such to see what the "range" may be. I didn't see it before so it might be a recent update. Scroll down the page to see, it's roughly in the middle:

Model S | Tesla Motors Canada