Hacker News Reader

Comment by bencpeters | Hacker News Reader

This might not be as much of a problem for most of the target market, but I was really excited about the Tesla X until I heard about the doors - meaning no roof rack options at all. Here in Utah, I would love a nice, capable car in the snow with plenty of room for gear, but if I can't put mountain bikes on the roof or a roof box with skis on it in the winter, it's not very useful...

Maybe I'm just not in the target demographic, but I can't imagine I'm the only one who wants roof racks on my electric SUV...

View on HN

I think the Model X will be ultimately be disappointing for anyone who's looking for a SUV from a capability standpoint.

Really, the first hint is right there in the marketing copy: "the best of an SUV with the benefits of a minivan" - which translated means "we know minivans are the most useful vehicle for families imaginable, but nobody likes buying a minivan, so we've made a vehicle that tries to have the functionality of a minivan, while not looking like one."

On paper, minivans are spectacular for families. They're affordable. They haul people in relative comfort, they're easy to get kids in and out of, they drive well, and they get pretty good MPG.

On reality, very few people actually want to own one. Ergo, millions of Americans drive SUVs who would really be better off in minivans. Which has led the industry to make lots of SUVs that try to offer the utility of a minivan, in a different form factor.

In doing so, they lose the "Utility" part of the SUV acronym, or at least lose its traditional meaning. Out of the modern crop of SUVs, there are very few that could handle anything more arduous than a carefully grated dirt road. Which really, is fine, because how often does your average family-mobile need to ford a stream?

Discounting the awesome technology and innovation, that's essentially what Tesla is trying to do with the Model X. And while I find the Model S stunning, this vehicle remonds me of the Buick Rendezvous, Pontiac Aztec and Toyota Venza. Not particularly stunning cars.

I sincerely hope Tesla is successful, and I'd love to own a Model S, but I'm afraid the styling of the Model X is a step in the wrong direction. Every time I've seen a Model S in person, I think, "That's a great looking car." I fear few people will have the same reaction to the Model X.

As I recall, the history is basically this:

SUVs became very popular and displaced minivans as the preferred family personal transport because the car companies put lots of money into promoting them for that rule after government safety and other standards that applied to regular passenger autos were extend to apply to minivans.

(Minivans were largely created and marketed as a major class as a response to those standards being applied to passenger autos in the first place; before minivans, the role was filled by station wagons.)

The "utility" function of SUVs was central, they weren't really called SUVs and weren't nearly as popular.

And crossovers blending SUVs and Minivan features are a result of many of those standards now being applied to SUVs, making the distinct class less valuable to the automakers, allowing them to focus more on the market and less on gaming the system. But, without an incentive to game the system, there's also no incentive to create a big marketing push to overcome the preference for SUVs that passed game-the-system marketing created.

https://twitter.com/elonmusk/status/168014307009892354

I'm not sure you want to drive an electric car in the snow. Not that the torque wouldn't be great, but the cold would wreck your range.

It sure does, at least when you need the heater. In a conventional car, you'll get lots of extraneous heat from the engine, so heating is basically free. In the case of an electric car, an electric heating elements must be used with the same battery power as the electric motors. That is bound to hurt the range.

Even if you don't use the heater, cold weather reduces the effectiveness of the chemical reactions needed for a battery to supply power, causing the battery to drain faster (sometimes substantially so) and the Tesla is all battery.

I have driven a Tesla Roadster for 3 years. The heater does not impact range much.

In what climate?

Now, those electrical engines, electrical though they may be, still don't have 100% efficiency. I don't know how many kW the Tesla engine is putting out, but even at 90% efficiency you still have 10% of all that power wasted as heat. That's a lot of heat. Maybe it could be used for heating?

I'd be interested in finding out more about this. My parents (who live in NH, which gets its fair share of cold days) have a Prius and don't notice any mileage hit in the winter - in fact not running the A/C seems to help things more than cold would hurt. But there's definitely a difference between a hybrid and a full electric...

I suspect the hit is less for a hybrid, because in a regular Prius, the battery is basically used as a buffer, not a giant energy store. I have a plug-in Prius and my "pure EV" range (this is how far you can go without firing up the gas engine at all) is significantly shortened by cold weather. I haven't done any obsessive tracking of it and I've only been through one winter, but I'd say it's somewhere around 25% reduced capacity in the winter.

You're right, a plain hybrid is substantially different here.

A regular (non-plugin) Prius will go maybe a mile on the battery alone, and only in the right circumstances. Acceleration on the battery is poor, and battery-only mode is limited to 40-45MPH. It'll start the engine for you on demand, so this is no problem when driving, of course, it just illustrates that the battery performance isn't all that important.

Depending on how you drive it, cold weather can hurt gas mileage. If you're driving in a way that the engine doesn't run much, then it may have to run the engine more to generate heat for the heater. However, if you're driving in a way that runs the engine a lot anyway (highway driving, decent amounts of acceleration hard enough to require the gas engine, etc.) then you get the same kind of "free" heat as a normal car.

One interesting point: you mention acceleration. The battery-only acceleration on the plugin prius is actually pretty acceptable. I recently rented a regular prius and my habit of accelerating as fast as I can without busting out of "eco" mode meant I was just crawling embarrassingly slowly, whereas in the plugin, you tend to outrun most average drivers if you do that.

The battery makes a big difference. Since it's just a helper on the regular Prius, it doesn't have to be all that powerful, and I think it's only rated for something like 30-35hp. On the plugin, it needs to be able to drive the car on its own in a reasonable fashion, so it's much more powerful, as well as the obvious thing of having a higher capacity.

Driving my Prius v, I'm battery-only basically when cruising on surface streets, sitting idle, or maneuvering around small, slow residential streets. And maybe, maybe if I'm accelerating away from a stop on a decent downhill slope with nobody behind me.

Winter gasoline is 2-8% less efficient than the summer blend. My Prius's mpg, that I've never reset since buying the car, goes down slightly in winter, and back up when the switch the fuel back, only by a few mpg, and less now as it's averaged over many more miles. Now at 49.1 (uk gallons)

Indeed, in a regular 2008 gasoline car, I notice a 0.2 liters per hour drop in idle power consumption if the AC compressor is off.

I live in the Yukon and we regularly have -40C/F for a few weeks a year, and a solid 3 months where it doesn't get above -30C, and hovers into the -40s at night.

My friend here has a 2011 Toyota Highlander Hybird, and she barely notices a difference in range year-round.

Hybrids do not store energy for the journey in the batteries, they store it in the fuel.

The storage capacity of the fuel is not affected (much) by temperature.

From a simple perspective, the batteries in a hybrid just serve to smooth out the energy demand and provide regenerative braking.

Wasn't there a NYT test drive where a really cold day affected range?

Yes, that is exactly what the problem was, though it got lost in the drama.

The car has a protection mechanism to prevent the battery from freezing, and when left over night in the cold without a charger, it will actually run an auxiliary heater to keep the battery warm enough.

The reviewer expected the charge to be the same in the morning, so he called their technical support when it was so low. They didn't explain that the charge can substantially decrease overnight when parked in the cold, because it automatically runs a heater for the battery. Instead they suggested that it was an erroneous reading, and that it would correct once the battery heated up.

It wasn't really a design flaw so much as a mistake from technical support exacerbated by an overbearing response attacking a journalist for not being omniscient.

Not as much as the fact that the journalist in question simply didn't charge it.

According to Musk, the range o an electric car will decrease by 10% if the temperature drops to -10 degrees Celsius

How about bike racks in the back? I wonder which placement is better for mileage due to aerodynamics: Top or back?

I generally do 2 in the back on a hitch rack, and 2 on the roof on my Subaru right now.

(but I realize that car shuttles requiring 4 40lb downhill mountain bikes isn't exactly your typical use case for a car! It's just an important part of what I personally need it to do...)

In my experience, bikes on the hitch rack hurt gas mileage less than the roof ones, but I haven't been super rigorous with the comparison...

But... ski racks! So important for some people, and there's nowhere for them to go except on top.

There are plenty of hitch-mounted ski racks (skis are held vertically).

Yeah, unfortunately, the doors also are a downside for me - I have limited garage side access.. The lack of roof-top carrier (which was the unsung hero of our last coastal drive) would be a downer too.

Despite all this, I irrationally yearn for this vehicle.

Reply on news.ycombinator.com