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Comment by calvinmorrison | Hacker News Reader

> Having a zero pollution power source lets the car do things that would be unsafe in a normal vehicle. Preheating, or precooling is safe in an electric car but can cause dangerous accumulation of carbon monoxide if running a fossil fuel engine.

Which is like, relevant inside a building only, at which point preheating and cooling isn't that useful

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>> Which is like, relevant inside a building only, at which point preheating and cooling isn't that useful

My garage in the winter would disagree throughly with that statement.

If you're going to preheat your car in the garage in the winter, you're probably better off installing a heat pump to heat the whole garage. Heating the car itself with its resistive heating is going to be very wasteful.

With EVs you need to heat the batteries, not just the cabin, so that's a huge amount of mass that needs to be heated up. If you try to run the batteries cold on an EV it's going to kill the range because current battery chemistry is not optimized for low temperatures.

Plenty of EVs have heat pumps as well.

Which would be great for heating up the cabin but I think too small to heat up the whole mass of the car including the batteries, especially if the temperature is below-freezing!

my model 3 with a heat pump does just fine for both cabin and battery in Canadian winter. My uninsulated, detached garaged built in the 1920s would be astronomically expensive and irresponsible to heat. Instead I spend about 10-20 cents worth of hydro to heat the car before I go somewhere through an app. By the time I get my coat and boots on the car is nice and warm.

There is also more than enough heat to get the battery into the right thermal conditions for optimal DC Fast charging on road trips when it's well below freezing. I have seen exactly the same charge curve in both summer and winter, peaking at 170 kW (max for Model 3 SR+) and slowly tapering.

Dog mode is so great.

I wish my Leaf had it.

Theoretically that is true. In reality, ICE vehicles limit their ability to do this based upon the assumption that they might be in an enclosed space.

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