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Comment by jbm | Hacker News Reader

My 2019 Model 3 is using more than twice its normal energy use in the Calgary cold; 293 wh/km vs 143 wh/km normally.

Thankfully, charging on a 120v output is fine but I only drive 30-40 km per day at a maximum.

It is not the same as a gas car or a hybrid; I knew this beforehand (and am only using it in winter due to an accident) but creating the impression that cold weather is easily handled is just not accurate.

Although, if I am being completely transparent, I think the main issue is that the roads are covered with snow and that is significantly increasing the rolling resistance. Clearing the snow between the tires and the wheel well is also super annoying when it is -30 C outside. (I wonder if this problem is just a design issue and not inherent to EVs, but it's not something I am knowledgeable about..)

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In the end, unless you're down with having the cabin be freezing during your drive, you're going to spend a good bit of energy warming the car. This energy was "free" in an ICE, but it has to come from somewhere in an EV, and that somewhere is the same place as where you get your range energy.

> This energy was "free" in an ICE,

Does that mean it comes from burning gasoline and it can be filled quickly anyway. Or that heating cabin is byproduct of running engine while driving?

It's the second one, and ICE typically uses energy that is otherwise wasted when it isn't cold outside. Mind you it has the effect that it takes longer to warm up an ICE car because you need to warm up the engine etc. before the habitacle gets warm where you cet there very quickly with an EV.

the latter

Yes but once the car is warm, it doesn't consume that much to keep température unless you open the doors, at least on my 2019 Tesla 3.

I found that pavement conditions, how much snow and ice is stuck to the car etc. have a bigger influence on range than temperature once the car is warmed up. The trips I did during or just after a snowstorn always required some careful management of charge and keeping a good buffer.

I do agree, snow/ice stuck to the car changes the aero drag a good bit and pushing slush definitely adds a lot of tire drag as well. This can definitely be a major factor.

I live in an area where it can get pretty cold, but usually in quick cold snaps and rarely a lot of snow on the ground. I've found preheating when plugged in completely negated the extra energy needs on shorter drives, but the longer 100mi highway drives still ended up needing a lot of energy to keep the cabin warm. And yes, it takes a ton of energy to go from a freezing cold cabin to warm compared to trying to keep things warm. Every time you stop for a few hours and then go again without having any external power to preheat you use a lot of energy.

I think the main issue is that the roads are covered with snow and that is significantly increasing the rolling resistance. Clearing the snow between the tires and the wheel well is also super annoying when it is -30 C outside.

Those also apply to ICE cars. EVs are getting hit in three vulnerable vectors at once: Cold decreasing battery capability, increase in friction, increase in aerodynamic drag.

Does your 2019 Model 3 have a heat pump? From watching Bjørn Nyland on YouTube, it seems like having a heat pump makes a HUGE difference in a cold climate.

Sadly no heat pump on a 2019 M3; no way to retrofit it either. A companies offers battery insulation solutions —but I don't know if I trust a solution that alters the heat transmission properties of a battery.

(The previous owner of my car had a heated garage but that might be too extreme a solution for me.)

My MY definitely builds up ice in the wheel wells a lot worse than any other car I've had in snow climates (VW R32, F150, 4Runner, Subarau Crosstrek). If we don't remember to clear them every day, they can build up and freeze into glaciers that limit the car from turning.

I'm impressed 120V works for you! The first year we owned it, we had to get a charger once the winter hit. At 120V, it was estimating up to 24 hours of pre-conditioning before it would start charging. And our winters are pretty mild in comparison (Tahoe, CA).

I was not planning on driving it in winter; sadly my main drive got into an accident and I had to pull it out of storage.

However, even at worst, I might use 60% of the battery in a day. I can easily charge 20-30 overnight so I generally make it back over a few days. Having a few bad days might result in me hitting the free L2 charger at the grocery store for an hour or two.

It isn't optimal so I've been looking at switching my garage door to a 240V charger. However, in actuality, I haven't had any major problems so holding off until I renovate the garage makes a lot of sense (I am planning on adding ground mount solar from which I intend on charging it but that's another story)

Oh; and likewise, I've never had a car build up so much snow. I assume it is due to efficiency or whatever, but my Toyota Sienna and my old Ford Mustang never required me to really get rid of all the snow to drive normally. Calgary also doesn't really plow the snow, so it's a problem on the once or twice a month that it snows and a few days after (until the snow melts)

Fortunately it looks like we'll be back above freezing next week (was winter really this brief?)

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