Hacker News Reader

Comment by trymas | Hacker News Reader

So what is the exact problem?

Batteries - everybody knows that the voltage drops in cold weather. This is of course big issue in the electric cars, but is an issue with a gas cars too. Bellow -20C, you will start to feel that it's harder to start a car, even with rather fresh battery.

Car door handles, what the hell is this problem? You need to lube door handles and door rubber gaskets (sorry if terminology is wrong) for probably every car if you do not want to have _any_ trouble in seriously cold weather. Stickier door handles or door freezing to the car's body is usual occurrence for me every single winter.

View on HN

It's mostly a problem in as much as people are simply not used to how they are effected. E.g. I grew up in Norway. People cared more about garages or having electric motor warmers than elsewhere to ensure their cars would start. My dad would turn on heating in the garage every morning when he woke up during winter to ensure the car would even start when he was ready for work.

But those are different issues to e.g. losing range faster. It'd taken people a long time to learn what to expect from a gasoline car in cold weather, and a lot of time for manufacturers to minimize the problems as well.

It'll take time for manufacturers to optimize for that different set of challenges, and time for car owners to get used to different considerations.

There have also been reports of the door electronics failing entirely in cold weather. Since the electronics fail, you can't get the door open due to the design requiring electronics to open the door in the first place, so you can't get into the car to turn on the heat to warm the electronics.

> Car door handles, what the hell is this problem?

The design leaves you nothing to grab, like a more traditional car door that can be grasped?

> so you can't get into the car to turn on the heat to warm the electronics.

All Teslas, especially the M3 since it doesn’t even have a traditional key fob(I think they’re going to start selling those for the M3 as well), have remote lock/unlock and remote controlled heating from the app, so that’s a non-issue.

IIRC the remote unlock means the door will open once you pull the handle. It doesn't actually unlatch the door so you could just pull it open. If the electronics are on the fritz, you can't unlatch the door.

With a software revision, the door could actually open with the app.

I think they don't want to do it because they're worried if you open the door with the car in a slope, it could swing into the road or hit another car. The door has no way to close itself too.

The door handles on a Tesla are an issue in normal cold weather already [1] although I am not sure if the model 3 has the same ones as the X. Most cars you can yank the door handle open even if it's iced up.

[1] https://youtu.be/ezqwfha-BZ8?t=498

"Car door handles, what the hell is this problem?"

Teslas have door handles that work differently from ordinary cars, and that seems to cause problems with freezing weather. Different models have different mechanisms, but the root cause seems to be the desire to have the handles lie flush for the sake of appearances.

Actually I think it has less to do with appearance and more to do with efficiency as every mm counts in an electric car drag coefficient.

Priuses don't have this problem.

Prius handles only affect MPG, which is a number people care less about than miles of range.

I don't follow — MPG and range have a direct, linear relation. They're also one of the most aerodynamic, low drag coefficient vehicles on the market.

This table on wikipedia[0] puts the Model S and Prius at the same coefficient: 0.24. The Model 3 is a rounding error better, at 0.23. The Model X is a rounding error worse, at 0.25. Another list with helpful pictures[1] shows that literally every other low-drag mass market vehicle has conventional handles[1].

[0]: https://en.wikipedia.org/wiki/Automobile_drag_coefficient

[1]: https://www.motoringresearch.com/car-news-list/most-aerodyna...

You make good points about the drag coefficients, but I don't know if they're comparable in terms of handles — just because they have similar overall coefficients doesn't mean the handles don't affect drag. It may be the case that the Prius body is slightly more efficient, but the handles bring it back down.

Re: range vs MPG — range anxiety isn't an issue for hybrids, because filling up at a gas station is extremely fast. So having better MPG — which is more a cost metric (and to some extent a badge of feeling good about being eco-friendly) — is less important than having longer range on an EV, because when you exceed an EV's range it's quite a bit more painful than when you exceed a hybrid's range. Technically better MPG means better range assuming tank size is equivalent, but range isn't a number many people care about for hybrids; it usually doesn't appear in marketing, whereas MPG does (and typically without tank size, so range isn't even deducible). For EVs range is one of the headline numbers, whereas MPGe typically doesn't appear in marketing.

Why wouldn’t ICE cars be equally affected by car drag coefficients?

Fuel is cheap. Nobody cares about that extra 0.2 mpg.

For electric it's an amplified effect, because a slightly lower drag coefficient means less energy use per mile, which means you can have a smaller battery, which in turn means lighter, which is again less energy per mile.

They are, but range is not as big of an issue with ICE, so less pressure to optimize drag coefficient

If electric cars are more efficient, doesn't that mean every mm counts less than on a gasoline powered car?

Its not for appearances, solely. It improves aerodynamics of the car, and reduces drag. I believe it improves efficiency by about 5%.

5% seems an awful lot for a couple of door handles.

I'd guess the previous comment needed to say

"5% compared to existing doorhandle designs"

> I believe it improves efficiency by about 5%.

5% efficiency of what? Extracting money from gullible customers wooed by gimmicks perhaps.

It's certainly not making the vehicle 5% more energy efficient across an entire typical discharge cycle, where accelerating the beast is the domimant factor and is entirely unaffected by doorhandle streamlining.

Removing sideview mirrors, reduces drag by about 5%

http://publications.lib.chalmers.se/records/fulltext/143193....

Removing the doorhandles, would also reduce drag.

You're making flawed assumptions about the alternative doorhandle design.

I have owned multiple cars as far back as the 80s having doorhandles flush with the body, without involving any particularly fancy or electronic gimmickery.

https://en.wikipedia.org/wiki/Honda_Insight#First_generation...

Those are not flush in the sense of the Tesla handles - they have a depression to insert your hand.

[obvious]

Are you familiar with the concept of diminishing returns? Tesla is like Juicero in this regard, but they're at least somewhat selective about it focusing on areas the consumer directly interacts with which improves sales.

One of the managers I work with has a new Model 3. The window has to roll down slightly in order for the door to open, so if the window gets stuck then the door is stuck.

Reply on news.ycombinator.com