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The cold hard truth about electric vehicles in winter

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Re: The cold hard truth about electric vehicles in winter

#151

Post by kevin_thibedeau »

scott_siskind wrote: post #122
kevin_thibedeau wrote: post #98

Earlier quoted context omitted.

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.

> It is very noticeable on a bicycle at high speeds Huh? I've been cycling for 15 years, many of those years doing 15k km a year, all year round. Mountain biking on mountains at -15C, down to urban cycling in 38-40C scorching summer heat. I've never noticed speed, effort, stamina changing with temperature as you suggest. And I've done lots of road cycling at constant 35-40km/h, descents of up to 70+km/h.

Track your time on a consistent route on paved, snow free roads. I guarantee you'll see a dip in winter.

Scorching heat with high humidity has an opposite effect. H2O drops the density of air and you can go measurably faster than in drier air.

Re: The cold hard truth about electric vehicles in winter

#152

Post by Scoundreller »

simfree wrote: post #100
midasuni wrote: post #87

Earlier quoted context omitted.

18mpg is 21mpg with U.K. gallons. My fairly large Skoda gets 45-50 in the real world, maybe dropping to 42 if I’m pushing it to 85mph on the motorway. Even back when I owned a mid 80s Nissan around 2000 I was getting 25mpg (us gallon). Why is US mileage so awful?

Large SUVs with overcooked engines to meet emissions requirements (lower PM2.5 emissions at the cost of slightly worse fuel economy) get bad mileage. Having all wheel drive or 4 wheel drive, high ground clearance, a poor aerodynamic design (driving 70mph or 80mph sounds bad in many of these cars) also hurts efficiency.

Even when it comes to cars, often the US base model has a larger engine than the EU base model.

No idea why: speed limits are often higher in EU and often with more hills.

Re: The cold hard truth about electric vehicles in winter

#153

Post by vosper »

Scoundreller wrote: post #142
rtkwe wrote: post #105

Earlier quoted context omitted.

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.

There’s no particular reason that a dryer and washer have to go in the same room. I have my dryer in my garage, because it’s a hybrid heat-pump model that is very efficient when the garage is warmed up from the afternoon sun, but can provide its own heat in winter. It captures all the water in a tank, so doesn’t put any moisture into the room. Modern dryers are really quite neat :)

Re: The cold hard truth about electric vehicles in winter

#154

Post by kevin_thibedeau »

gambiting wrote: post #107
kevin_thibedeau wrote: post #103

Earlier quoted context omitted.

No. That's a waste of a useful resource. It's also illegal in various places.

Well, I envy wherever you live then, must be nice in winter!

It's 13F right now. I can afford clothing.

Re: The cold hard truth about electric vehicles in winter

#155

Post by Scoundreller »

bumby wrote: post #139
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…

There’s a reason why many northern areas (esp. Canada) have diesel trucks that come equipped with a plug-in block heater.

There’s often not-very-visible differences between Canadian and US car models, even base models.

Canadian BMWs will all have the “cold weather package”, which for me means heated seats and an H8 battery instead of a smaller H6.

For my mom’s old Corolla, it means a 1.6kw starter instead of the 1.4 in the US models (which became a sorta problem when I bought a refurb at a Canadian parts store…)

Re: The cold hard truth about electric vehicles in winter

#156

Post by pastage »

scott_siskind wrote: post #122
kevin_thibedeau wrote: post #98

Earlier quoted context omitted.

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.

> It is very noticeable on a bicycle at high speeds Huh? I've been cycling for 15 years, many of those years doing 15k km a year, all year round. Mountain biking on mountains at -15C, down to urban cycling in 38-40C scorching summer heat. I've never noticed speed, effort, stamina changing with temperature as you suggest. And I've done lots of road cycling at constant 35-40km/h, descents of up to 70+km/h.

I am not really contradicting you here. Just want clarification from GP. My reaction was Huh? As well.

With N=15 years of gps data and 40-70 of those days per year below zero very few below -10°C. I can say that I ride slower on cold days on avarage.

I am not fit and do not track that at all. I can barely keep my avarage above 25km/h in city traffic for 15km, very few conflict points maybe twenty but not comparable to road cycling. So a km/h decrease of avarage speed during winter is common but not a given. I do not count bad road conditions, but Stockholm has really good maintanance during winter, ice free asphalt all year.

Re: The cold hard truth about electric vehicles in winter

#157

Post by trentgreene »

Swenrekcah wrote: post #131
alphabettsy wrote: post #118

Earlier quoted context omitted.

> Remember that a lot of people have to spend 10-15 minutes warming up their cars before they drive them in cold weather. People choose to do this. This isn’t required and it’s recommended against in modern vehicles. > I do not want to go into details, better car mechanics than me should, but there is all kind of chaos that can happen if your engine freezes and you try to drive it immediately. Engines do not freeze i…

> People choose to do this. This isn’t required and it’s recommended against in modern vehicles. I’m curious about that recommendation, do you know why that is?

Because it’s much more efficient to heat up a modern car by driving it than it is to let it idle.

Re: The cold hard truth about electric vehicles in winter

#158

Post by bumby »

trentgreene wrote: post #146
kevin_thibedeau wrote: post #98

Earlier quoted context omitted.

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. A…

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

Not likely, as an increase in air is going to be accompanied by a corresponding increase in fuel. Unless your fuel mapping is all messed up, it will give you more power, but not likely better fuel economy.

Re: The cold hard truth about electric vehicles in winter

#159

Post by Scoundreller »

vosper wrote: post #153
Scoundreller wrote: post #142

Earlier quoted context omitted.

> 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.

There’s no particular reason that a dryer and washer have to go in the same room. I have my dryer in my garage, because it’s a hybrid heat-pump model that is very efficient when the garage is warmed up from the afternoon sun, but can provide its own heat in winter. It captures all the water in a tank, so doesn’t put any moisture into the room. Modern dryers are really quite neat :)

> There’s no particular reason that a dryer and washer have to go in the same room

Uhhhh convenience? People prefer them right next to each other so that clothes washing isn’t a long journey. At least that’s why the plumbing and electrical/gas connections are usually built close to each other.

Re: The cold hard truth about electric vehicles in winter

#160

Post by Manuel_D »

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.

Colder air's increased density and bigger temperature gradient also improves the efficiency of internal combustion engines.

Increased rolling resistance from displacing snow is a far bigger cause of winter driving inefficiency.

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