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Comment by nikster | Hacker News Reader

Yeah - there are many use cases still where EVs are way worse or even totally inadequate. Yours is one. Cold countries is another (sorry Canadians... don't buy Teslas just yet...). EV performance is horrific in cold conditions.

But the majority of use cases at this point is - EVs are way better. City driving, less than 100 miles per day, which is what most people do in most countries, charge at home, etc.

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> EV performance is horrific in cold conditions.

If anyone knows about it, I'd be interested to explore this further.

My understanding is that in some parts of Canada it's common to plug your currently petrol/diesel car into an electricity socket overnight to provide a low-level of heating (otherwise the car would be impossible to start in the morning) - is this level of heating insufficient for an EV?

Alternatively how much electricity would be wasted spending some power to keep batteries at a warm enough temperature to prevent performance degradation when charging? Are we talking a few percent or a double/tripling of power costs?

The problem is not keep the battery warm while parked, it's keeping the battery warm while driving. Most EVs can "preheat" themselves before you start in the morning, the smart one's might even learn the patterns and be ready when you get in at 07:30 every day.

The problem is that driving EVs in the cold costs a lot more energy. I've got a Ford Mustang Mach E for about 2.5 years now. In the winter the range that Ford claims drops by about 30 to 35%. That is a lot of range that goes missing just because the temp drops below 5 degrees Celsius.

Luckily I'm the perfect EV candidate: my daily commute is less than 50% of the total range so I can drive 2 days to the office if needed. And I can charge both at home and at the office.

The main problem that I see is that people cannot charge at home. If you are dependent on fast chargers by the side of the road you are going to have a hard time. The downtime for fast-chargers is enormous: my personal guess would be that they do not reach the 90% uptime. Which is bizar problem to have because a fast-charger and remote monitoring of the charger condition should be a solved problem by now.

  > The problem is that driving EVs in the cold costs a lot more energy. I've got a Ford Mustang Mach E

Nowadays this problem is mostly just the Mach E.

The Mach E delivers heat in the most inefficient way possible: resistive heat[0]. Modern EVs from other manufacturers use heat pumps, which are much more efficient. There's still some drop in winter range (like gas cars), but it's nowhere near 35% anymore.[1]

Ford's system is also Rube Goldberg[2]: they use a water-based PTC heater to warm a small isolated coolant loop (complete with its own separate reservoir!), and then run a pump to send it through a liquid-to-air heater core. Obviously done for commonality with an ICE heater core, but the unnecessary weight and complexity shows the compromises to shoehorn an electric drivetrain into a ICE (or even "flex") platform.

[0] https://www.youtube.com/watch?v=00ejq7z4H6g&t=449

[1] https://www.autoevolution.com/news/here-s-how-much-range-a-t...

[2] https://www.youtube.com/watch?v=m1kHsd3Ocxc

>My understanding is that in some parts of Canada it's common to plug your currently petrol/diesel car into an electricity socket overnight to provide a low-level of heating

Kind of. Block heaters help warm the engine coolant which warms engine and the oil, making it less viscous and help it flow properly so that the battery doesn't need to work as hard to crank the engine. They're typically only 400w to 600w draw.

Modern full synthetic oil and a well maintained AGM battery makes it less necessary, it's just a little less wear on the engine overall over the long term. Most folks though don't spring for either since they're a bit more expensive then mineral oil and flooded lead acid batteries.

Your comment is more about the 'passive' heating to keep some bare minimum for the hardware to function, but a big part is the 'active' heating for the driver and passengers.

If we look at the total energy consumption for driving in cold conditions, then moving the vehicle along the road needs in the ballpark a similar amount of energy as what is required to heat up the interior of the car to a reasonable temperature and keep it there - cars aren't (and probably can't be) as insulated as houses, so they need quite a lot of energy to stay so much warmer than the outside.

In an ICE, most that heating is done from waste heat of the engine. In an EV, that comes directly out of your range.

> In an ICE, most that heating is done from waste heat of the engine

I don't think there is a car in production where the heating is coming not from the engine.

In any case, the key point is that in an ICE car the heating is mostly "free" since the engine has perhaps 40% efficiency and the majority of heat released by combustion is unused/unusable waste heat that might as well be used to heat up the car if you need to, but in an EV you don't have that source of free waste heat to tap into, and you have to use the energy that you could have used for moving the car instead.

Some cars do have additional resistive heating or heat pumping through AC, where that is technically driven by engine power, but not from the waste heat.

Implied "mass market, passenger".

Of course there are some cars which do have a resistive heating, but which are those?

> heat pumping through AC

Uhm, the compressor runs from the engine so while the heat is not from it, it's still directly relies on availability of running engine.

The small diesels like VW Polo etc have resistive heaters as otherwise it would take too long for comfort to heat up the cabin.

Also don't forget that seat heaters are also resistive and most cars in cold climates have them.

> Also don't forget that seat heaters are also resistive and most cars in cold climates have them.

I know it (or more like my bum) too damn well, though I didn't think about them in this case.

> small diesels like VW Polo

Makes sense, though as I understood, it's strictly auxiliary till the engine is heated aaaand maybe some additional heating at the parking lot with the engine turned off, though I would wary of this usage, it would drain even the extended battery fast.

Overall it's not quite what I had in my mind (think of space heaters), though yes, there are some parts which can operate independently from the engine, though it's not a primary function for them.

Thanks for the hint.

There's also these https://www.disco3.co.uk/wiki/Fuel_Burning_Heater that can be run with the vehicle engine off.

Yes in our experience, a 120V outlet is sufficient to keep the EV battery warm when the outside temperature is -30C. However, that's all it can do; it won't add any appreciable charge to the battery while it is doing so.

Yes, like that famously warm country, Norway, where 87 percent of the country’s new car sales are electric.

Norway is generally warmer than a lot of Canada. Most of the population of Canada don't get the warming of the Gulf Stream.

EV suffering range loss in cold conditions is well documented. Norway has tons of EVs purely because of massive government incentives.

Norway is rich. If electric cars weren't suited for Norwegian conditions, many Norwegians can and would buy gasoline cars instead. EV's sell well in Norway because they're both good enough and cheaper. If only one of those two conditions held they wouldn't sell well.

The bar for "good enough" is artificially lower in Norway when it comes to EVs. I'm not sure if you're aware just how huge the subsides are for EVs in Norway. They are trying to reduce these a bit and I'll be interested to see how that affects purchasing patterns. You're exempted from a punishing 25% VAT that gas cars are subject to first and foremost. Also, electricity is very cheap in Norway due to their abundance of hydropower.

https://elbil.no/english/norwegian-ev-policy/

I've got relatives in Norway and Denmark. All the ones in my generation can afford gasoline cars even though they cost ~twice as much. They would drive gasoline cars if electric cars sucked. They don't.

Electric cars would have to suck pretty bad for someone to spend twice as much, I'm not sure that anecdote is saying what you seem to think it is.

They might be saying "In an ideal world I'd drive a gas car, but the electric car is good enough where I'd rather not pay double." I don't think the person I was responding to was saying they "sucked", just that they had drawbacks.

A $25,000 base Civic is a fabulous car yet $50,000 cars are far more popular in the US.

The question becomes “is that loss important?”

I suspect people overestimate the frequency in which they drive 250 miles a day.

Yes.

No.

The nice thing about fuel cars is you almost never need to think about range beyond the refueling visit to a gas station once every week or two. If you're going on an extended road trip, you know you could skip a dozen gas stations and still be fine.

I drove an EV before alongside a fuel car, and I constantly considered whether the bloody thing had enough range for the day or journey. The constant mental load, light as it was, is something I don't have to deal with driving fuel cars. Having ease of mind is priceless.

I have the opposite. Some of my kids activities are almost 50 miles away. I have to think about whether there's enough gas in the gasoline car to get there and back. If not, we have to leave 10 minutes early, and that means you have to yell at the kids to hurry up, et cetera. Or when driving home you always have to ask yourself "do I need to fill up or not"?

OTOH, if the EV is at home, it's plugged in and is always sitting at 80% full. No load.

Strange, I’ve been driving EVs for seven years and I have just as much ease of mind as you claim to about gas cars.

Maybe it has more to do with how much you need to drive each day?

If you’re putting in triple digits of miles every day, then you have a very different set of constraints compared to someone commuting up to 40 miles a day, which is the United States average.

> The nice thing about fuel cars is you almost never need to think about range beyond the refueling visit to a gas station once every week or two.

If that's your frequency of gas fillups, and you have a garage charger, the same is true for an EV. (If you lived in an apartment where you couldn't plug in regularly, perhaps not.)

Here's the thing: I rarely ended the day on an empty tank. I always ended the day on an empty battery.

So there I was, constantly considering whether the bloody thing had enough range for the day. It's a worry I can do without, and so batteries will need to see exponential improvements before I'll consider one over a good old fuel tank and an engine.

This doesn't make sense to me. Average gasoline-powered car has 300-400 miles range, and you're filling up once every week or two? That implies an EV range of something like 80 miles?

Their tax and energy policy dictates what cars their population can drive. That 87 percent of Norwegians drive EVs really says nothing about the quality of ownership experience. Many could be annoyed by forced EV adoption in cold weather.

Norway is forcing EVs everywhere, generates tons of waste due to overconsumption of cars and uses oil money to do it. It's an abhorrent policy.

Norway: 323802 km²

California: 423970 km²

I have the other problem where I live. This past summer, we had almost two months of over 100F heat. There were days we were pushing 110F.

Skimming the Tesla forums, some said to estimate a drop in range of almost 1/3 in this extreme heat?

You'd be absolutely shocked by the amount of Teslas in northern Canada.

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