Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

The cold hard truth about electric vehicles in winter

axios.com

Post reply on HN
Print view View original

141–150 of 549 posts

Re: The cold hard truth about electric vehicles in winter

#141

Post by bumby »

kevin_thibedeau wrote: post #98
TedDoesntTalk wrote: post #59

Earlier quoted context omitted.

I live in place that routinely goes below freezing in winter. I’ve never noticed gas mileage change because of temperature. I would definitely notice a difference of 8 MPG. Where do you get that info? Is it personal experience? If so, where do you live?

Cold air is denser. Pushing it out of the way saps more energy and drops the effective work done. You're oblivious to it because a motor vehicle has so much available power on tap. It is very noticeable on a bicycle at high speeds. Conversely. Sailboats get more efficient in cold temperatures because more energy is imparted on the sail.

>Cold air is denser. Pushing it out of the way saps more energy

ICE mpg tends to drop in cold weather, but this isn’t why. It’s usually because it takes longer to reach optimal operating temp or due to changes in fuel composition. Cold air can produce more drag but that problem exists irrespective of ICE or EV.

The pumping efficiency is unaffected as any losses on the exhaust side will be offset by increased pressure on the intake side.

Re: The cold hard truth about electric vehicles in winter

#142

Post by Scoundreller »

rtkwe wrote: post #105
MBCook wrote: post #85

Earlier quoted context omitted.

But it was on level one charging (110v). A level two charger, even a slow one, should be able provide enough current to heat the battery and still charge the battery at the same time.

Most of the time if you're not at your own home you'll be on 110V chargers. To get 220V charging at someone else's you're likely either at another EV owners house who's gone through the trouble of installing a 220V port or you're lucky and they have a conveniently placed dryer in the garage you can steal 220V power from.

> conveniently placed dryer in the garage

That’s only a warm climate thing. Plumbing (of the associated washing machine) that’s prone to freezing is unlikely to be in the garage in cooler climates.

Re: The cold hard truth about electric vehicles in winter

#143

Post by jtc331 »

nradov wrote: post #132
jtc331 wrote: post #40

Earlier quoted context omitted.

Gas car range predictions are also regularly nonsensical. I thought this was well understood.

Perhaps that used to be a problem. The range estimates for gasoline cars that I've owned and rented in the past few years have been accurate to within a few percent, even in cold weather.

I expect that’s true over a full tank of gas but not when e.g. only 20 miles are left.

Re: The cold hard truth about electric vehicles in winter

#144

Post by swayvil »

fuoqi wrote: post #93
swayvil wrote: post #45

Flywheels. What's the state of the tech for that? Surly that's where we should be developing. Last I heard they're very efficient. In theory it has no ceiling, storagewise. And it certainly isn't constrained by a chemical reaction. The only downside is keeping it from blowing up. Right?

Are you suggesting to use flywheels as an energy source in EVs??? There is a heap of issues with this idea, the main ones: - They are VERY heavy. Typical energy density for flywheels is 10-40 kJ/kg (if you account for the whole flywheel), while Li-ion batteries and gasoline store 300-1000 kJ/kg and 46700 kJ/kg respectively (the latter does not account for ICE efficiency). - They are relatively big, since you can stor…

Yes, I understand the issues. They've used them in busses. Higher speed means more energy storage and ness necessary weight. Gyroscopic action can be handled with gimbals. Etc.

So back to my question.

Re: The cold hard truth about electric vehicles in winter

#145

Post by trog »

thinking4real wrote: post #89
marvin wrote: post #61

Earlier quoted context omitted.

Regular EV user here - plugging it in is something you do every time you park, the way you lock your doors. It takes five seconds. Press the «open charge port» button on the charging cable and stick it in the charging socket. Done.

I’m cracking up that you’re making this sound so simple and matter of fact, but reading this description of how one is “supposed” to charge their EV makes me realize i’m many years from wanting one. Honestly, it’s kind of a joke how badly people want to defend the tech despite its current shortcomings.

Not sure why "supposed" is in quotes here. You're "supposed" to fill your car with gas by waiting til you come across a gas station, driving in, parking at a pump, getting out, pressing the button to open the gas tank, plugging in the hose, pumping gas for as long as it takes to fill the tank to the desired level, paying, and so on.

Compared to plugging in an EV at night and forgetting about it and this being sufficient for 99 percent of my driving needs, getting gas sounds like it has vastly more shortcomings and that's before you look at any of the other crappy things about it.

Re: The cold hard truth about electric vehicles in winter

#146

Post by trentgreene »

kevin_thibedeau wrote: post #98
TedDoesntTalk wrote: post #59

Earlier quoted context omitted.

I live in place that routinely goes below freezing in winter. I’ve never noticed gas mileage change because of temperature. I would definitely notice a difference of 8 MPG. Where do you get that info? Is it personal experience? If so, where do you live?

Cold air is denser. Pushing it out of the way saps more energy and drops the effective work done. You're oblivious to it because a motor vehicle has so much available power on tap. It is very noticeable on a bicycle at high speeds. Conversely. Sailboats get more efficient in cold temperatures because more energy is imparted on the sail.

Hmm, I wonder if the increased resistance is overcome by the fact that ICEs can put out more power with colder denser oxygen rich air.

This is why performance cars sport cold air intakes. This is also why your car won’t hit its quoted 0-60 time in a warmer environment — those tests are normally performed or normalized to cold air conditions + 0% humidity. Just what counts as cold depends on manufacturer / reviewer.

Anecdotally, I track efficiency and drive consistent routes, and don’t notice a diff.

Re: The cold hard truth about electric vehicles in winter

#147

Post by skhr0680 »

simfree wrote: post #46
gambiting wrote: post #41

Earlier quoted context omitted.

But......EVs do work in cold weather? You lose a bit of range, but so what? My ICE car also gets worse mileage in winter. And if you're talking about extremes - then there's a reason why block heaters with external power connections are very common in certain places - even the best ICE struggles to start in -40C or less.

18Mpg becomes 10Mpg or worse in the winter in my experience. EV driving can be more efficient if you don't let your battery cold soak for hours, or equally inefficient if you do leave your car unplugged overnight.

In city driving my ICE gets 6-8km/L in summer and 8-10 in winter. On the highway it gets 10-12 in either season

Re: The cold hard truth about electric vehicles in winter

#150

Post by jakear »

jws wrote: post #73
GalenErso wrote: post #32

Earlier quoted context omitted.

Meanwhile, with an ICE car, you don't need to worry about having a garage, nevermind a heated one; the right charger, warming a pack, losing fuel overnight, or taking three hours to fully charge. I can pull up to any gas station and fill my tank in 2 minutes. And my gas isn't magically evaporating if it's a little chilly. The 30 different requirements for EVs to work in cold weather are too complex and prohibitively…

Spoken by someone who's never had their diesel fuel begin gelling in the fuel line at night on a frigid, remote highway and trying to figure out if you can make it to somewhere with heat before you stop completely. Then finding out they only have gasoline, so you try to figure out how much gas you can add to the diesel tank to keep it from gelling but still run adequately to move you along. Sometimes we forget that w…

> But you know what I don't do? Freeze my ass off standing in a gas station in subzero temperatures and howling winds! Not missing that at all.

Sounds like it's time for you to vote for the prohibition of self-service gas stations!

Post reply on HN