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.
Conversely. Sailboats get more efficient in cold temperatures because more energy is imparted on the sail.
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.
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.
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.
That seems to be born out by using better (read more expensive) winter riding gear. I naturally run a bit cold so spending on low temperature tights, base layer and jersey/jacket has made a massive difference for me.
Obviously there could be many reasons for this: less aerodynamic clothing, more cautious cornering etc etc, but the effect is very noticeable to me.
Winter fuel efficiency is worse because of a winter fuel mix, not because of air density.
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.
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.
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.
Increased rolling resistance from displacing snow is a far bigger cause of winter driving inefficiency.
That makes absolutely no difference at all.
That would be very surprising if it were true, given the very large effect density altitude has on airplane performance (engine and wing).
Note that it's 3% per 10°C delta so, for a 40°C swing (say 30°C/86°F summer to -10°C/14°F winter), that's a 12% difference in aero drag force.
Opening your window makes far more of a difference.
It's just about observable with very light and very aerodynamic aircraft at ground level if you can get them cold enough.
At -10°C/14°F, with no other adjustments, in the hands of a test pilot, that aircraft will have a ground roll of around 1000' and clear a 50' obstacle and come to a stop in around 1500'.
At 30°C/86°F, with no other adjustments, in the hands of a test pilot, that aircraft will have a ground roll of around 1150' and clear a 50' obstacle and come to a stop in around 1750'.
Flying in and out of 2000'-2500' strips with trees, it's impossible to not notice the performance difference with temperature. Perhaps the pilots who can't notice those differences don't fly into anything other than very long runways, but I don't think very many pilots miss the differences.
Dropping from 18 mpg to 10 mpg would increase your cost of fuel by 80%. It'd be hard to be oblivious to it.
I actually just looked at my economy graph, and I can't tell how much winter affects it. The variance is less than the variance of my driving habits. So less than 20%.
Idling combustion vehicles is bad, but sometimes it's a necessary evil to ensure visibility so the driver can avoid harming other road users.
Not really, you're spending a fraction of the fuel you'd use per minute if you were driving.
So, in terms of pollution it's no worse than taking a short detour to wherever you were going.
> Not really
Yes it is, it’s bad on the engine.
Defrosting and toasting the cabin to 92F in freezing conditions usually burns about 1.2kWh to 3kWh while plugged in, but that is just a few tens of cents (or free depending on the charger) to get nearly instantly toasty and ready to drive.
$10 to $30 a month in power use to keep your battery toasty in the dead of winter isn't too bad a price IMO
Also, electricity supply isn't prone to supply shocks when Russia invades Ukraine, or the Saudis want to flex their muscles.
Even back when I owned a mid 80s Nissan around 2000 I was getting 25mpg (us gallon).
Why is US mileage so awful?
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.
No idea why: speed limits are often higher in EU and often with more hills.
That sounds like nonsense. What were you driving that had such a reduced mileage?
Your car must be faulty.