I’m more curious how the cabin heating works. Certainly the waste heat from the motor has been enough for the battery in the past; is it enough for the battery & the cabin without a PTC heater when it’s -5F out there? We shall see. I’m sure Tesla tested the daylights out of it but I still want to see it firsthand. Happy wife, happy life applies here. She expects a sweltering cabin in the winter ....
Exactly the same situation here - I can put up with a colder car, but others will not. I'm hopeful the heat pump allows someone to keep the cabin at 76F on a mild winter road trip even down to 20F without as dramatic of a range hit as it would have been previously.
The way I see it, the solutions for -5F and expecting a scorching cabin are:
1. Very large battery - this is expensive, but for long distance travel at -5F, it's going to be a must anyway. For others, it's added weight that won't usually be needed assuming they can charge at home. Still, range will be limited if you're drawing the heat so much and at low temperatures.
2. Improved insulation for the battery pack - if the battery pack was designed specifically for winter use, they could increase insulation to help it retain heat. This doesn't work well in the summers when you want to shed heat however. In the winter, you could theoretically charge the car overnight before a road trip and have it finish charging in time for your departure, generating heat and even maintaining it while you're plugged into the wall. As you drive, you might be able to draw on this. When the temperature gets that low today, the battery pack doesn't retain all of the heat and is why supercharging on a winter road trip can occasionally be painfully slow.
3. External heat - someone posted a video a while ago of their Nissan Leaf outfitted with fuel heating. I forget if it was natural gas or another source. This actually generated a lot of heat and reduced range loss in the winter. I doubt we'll see something like that in a Tesla where you have to add CNG into an otherwise full EV. Electric buses in NY and other cold climates use this approach though. It's EV for everything except cabin heat.
Tesla might just be limited by current technology and design around the more common use cases, which are driving a little below freezing, but not trying to do road trips at -5F. I think it's popular in Norway where it gets very cold, because of incentives and because the distances most people need to go are relatively limited.