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Heating is relatively significant, it can take 10-20% off the range in theory. EV’s can solve this problem in a variety of ways:

i) Preheating the cabin from mains electicity, either predictively or through user command.

ii) Using heat pumps to scavenge and move heat around different parts of the car. If you’re early in a road trip you would have enough power in the battery to heat the car for a day or more. If you’re later in the trip there will be a lot of heat in the batteries and motors which can be shifted into the cabin. Similarly heat pumps can be used in reverse to scavenge heat from the cabin and frame to keep the batteries warm if the car is left outside for a long time without being plugged in. Batteries don’t like dropping beneath a certain temperature range.

iii) Simply increasing heat insulation. It’s not difficult to insulate better, it’s just it hasn’t been needed, because there’s so much wasted heat energy in internal combustion vehicles. A human is a 100W space heater, I’d imagine you could quite easily design a cabin for a small car to hold temperature even in the absence of any other heat source.

> you could quite easily design a cabin for a small car to hold temperature even in the absence of any other heat source

In my experience most cars do hold temperature for at least 20-30m with vents closed. You still need air exchange though for longer periods, so losing heat is unavoidable.

My hunch is that heating is pretty insignificant compared to the huge power needed to move the car, like single digit percentage. But I like your question at the end and would be interested in someone running the numbers.

edit: Ok here we go - Model 3 users report using about 240 to 300 watt-hours per mile. So I think that means a 1KW heater for an hour is equivalent to about 3 or 4 miles of range.

Note that the heater in the model S/3 is capable of ~6/4 kW. In most cases you won't be running the heater on full for an hour, but at -10 you might be. When you start talking about 12-24 miles of range per hour, that's how you get up to the worst case of ~20% range loss.

Still, that just means you want to limit your -10 degree trips to like 2.5 hours instead of 3 hours, and only if you don't have access to superchargers.

A traffic jam is probably about the best place for your car to die in freezing weather. Just hop out and sit in the car next to you, until they run out of heat.

Seat warmers are a good way to warm up with less loss.

That's why even the no-frills Nissan Leaf S has multiple seat warmers and steering wheel warmer. It's as much a range extender as a luxury feature.

Batteries heat up during discharge. So outside of the most extreme weather conditions more batteries are simply a better system.

Yes, but if I have more batteries I'll already factor that into my planning so I'll make fewer stops. If I have to always maintain X% battery when I'm driving in cold temps (to be able to survive N hours in case of a cold weather traffic jam) then it effectively just shortens the range. Adding X% battery to compensate this has to be very expensive compared to having a burner space heater and a gas/kerosene bottle for emergencies.

There are other ways to survive in the case of an emergency. Blankets, food, candles and whatnot should be in your emergency kit regardless of what you're driving.

Besides, how is this different than a gasoline-powered vehicle? In your situation, you'd still be reducing your range by X% in order to survive N hours in case something happens- your gas tank is not infinite, after all. I suppose you could make the case that you currently have more refueling options than recharging options, but I don't think it will always be that way, and it's not currently that was in some locations, such as Norway.

> Besides, how is this different than a gasoline-powered vehicle?

My gas car has a 700mi range so its simply not an issue as I tend to not drive that long on a day trip. I have the X% fuel spare for N hours of emergency heating so long as I do say < 600mi/day. I can drive indefinitely in my gas car while keeping the fuel meter over half tank and that doesn't cause any inconvenience in terms of extra stops. Doing that with an EV (never going under say 50% charge) would be inconvenient.

The same would be true for battery cars once the range is enough. And the problem of course would exist for an ICE car with a shorter range.

Doing a few simple searches online, most gasoline cars do not have anything close to that kind of range, unless you're "hyper-miling" or something. What the hell do you drive?

This is pretty normal for full size modern diesels (65L tank and around 6L/100km). This one in particular is a B8 Passat wagon.

Range is range, your space heater idea is just a less useful plug in hybrid. Spending less money on batteries to add another system that you use a few times a year results in a generally less useful car.

It depends on the relative cost of "N hours of heating in the form of more batteries" vs "cost of a burner heater capable of N hours of heating". If the costs are even nearly comparable (if they aren't 10x apart) then I agree with you there is no point.

The heater also can't be as complex as a plug-in-hybrid, requiring expensive serveice etc. It needs to be cheap, dumb, optional (so you only waste the cargo space on extreme long journeys and in cold weather) etc.

What I'm picturing isn't a complex system. It's a camping burner with a hose to the car's ventilation system. Think < 1cubic feet and sub $1k.

1,000$ of batteries = 1kw of resistance heating for ~8 hours and that’s improving over time.

Now, I am not sure how much reserve heating you want, but it’s much closer than 10x cost wise.

3-4h 1kW heat sounds reasonable. If that's less than say 3% of total range, or less than $1k extra battery then I'm confident it's a sufficient solution.

Model 3 users report using about 240 to 300 watt-hours per mile. So I think that means a 1KW heater for an hour is equivalent to about 3 or 4 miles of range.

So a 1KW heaster for 4 hours would lose you 16 miles of range.

Is this what's done? The Tesla fans air over the batteries into the cabin?

How is this problem specific to EV's?

Only because they have shorter range. I explained in another comment why the specific problem (Given the distance to be driven and the range) doesn't occur for my current ICE car.

Edit: and yes as was pointed out in another comment - heat is "free" while driving because of losses in the engine.

There is waste heat produced by the engine of a traditional vehicle, which is used for heating. The EV doesn't have this advantage.

Internal combustion engines throw off heat whether you want them to or not, plus the total amount of energy stored in a gas tank is vastly greater than a battery, so wasting some of it as heat is less likely to strand you. EVs only get similar range by being much more efficient, and efficiency means less energy lost to heat.

Depending on the car and the temperature you'd much rather be stranded in a Tesla (or another EV that works as well at low temperatures). A Tesla can run its heater on full blast for well over 12 hours. In ICE cars that don't have resistive heaters, the heat output is much lower at idle- think a civic or corolla. It can be risky to fall asleep in cars like this because you need to warm up the engine regularly or the cabin will become quite cold.

Having slept in quite cold temperatures in cars during longer trips quite a lot of times, just having the car idle over-night has always been enough to keep the cabin warm enough to not even need a blanket. Not talking about luxury cars with huge engines either. It also uses very little fuel. After 8 hours, you can see that the fuel gauge has moved, but only very slightly. I'm pretty sure a ICE car with a full tank can idle for several days before running out of fuel.

Simple, get an RTG a la The Martian...

If you’re willing to drive at 25mph your range is at least 700 miles :)