I’ve heard that EVs are bad in cold weather. What should I keep in mind?

The first thing to keep in mind is that EV’s aren’t bad in cold weather. In some ways they are much better than ICE cars (said with irony, given that Internal Combustion Engine acronym). Cold weather certainly affects all cars, it’s just with an EV you can measure it more accurately and you don’t have that extra benefit of all the wasted heat energy from a gas engine.

There is no avoiding some range loss associated with cold weather, due to simple lithium-ion battery chemistry. That, plus the need to heat the cabin without burning fossil fuels and using that heat byproduct, will give you some range loss in colder climates. A good rule of thumb is expect 10% range loss for temperatures around 50F and 20% range loss for temperatures around freezing.  Maryland doesn’t typically see temperatures past that, but the colder it gets, the more range you’ll lose. Extreme heat would have a similar impact, although exact numbers are not available.

Are there any other things I should consider when doing winter driving?

Yes. There are several other items to keep in mind for winter weather (e.g. snow and ice and freezing temperatures):

  1. Especially in slippery conditions, turn on Chill mode so you don’t accelerate your way into a ditch.
  2. Along those same lines, set your Regen mode to low if you can (later cars with later software may not have this option), so Regen braking doesn’t cause unwanted tire sliding.
  3. Others have had problems with folding mirrors getting frozen, so turn off the auto-fold option in the car’s Settings.
  4. If you can, preheat the cabin using your smartphone app to melt off any snow and ice on the windows and doors.
  5. In freezing conditions, run an old debit card along the bottom of the window to break the seal so the glass can slip into the door when opened.
  6. If the door handles or charge port won’t open because they’re frozen, the official recommendation, past pre-heating the cabin, is to give it a fist bump to break the ice (without, it should be said, breaking anything else). Pouring hot water or using cellophane have been mentioned, but that just risks more freezing and/or more plastic pollution, and should not be necessary.

Tesla’s official support page on this topic can be found here.

Do I really need all wheel drive (AWD) or winter tires in Maryland?

That question is actually two questions. The first one, do you really need all wheel drive, is more about the benefits of AWD in general. AWD provides more performance and better handling, with slightly less range. Whether or not you “need” it becomes personal preference. If the concern is over winter driving, unless you get a whole lot of snow in, say, western Maryland, then you probably do not “need” AWD. But you do need winter tires.

Winter tires in rear wheel drive cars give you much more control in wintry driving conditions than AWD without winter tires. Teslas by their basic design handle very well already, but bad tires won’t help whether two or four provide power.