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ICEs are significantly less efficient at startup and until they get up to their normal operating temperatures. That's not so much a problem for long range trips, but taking multiple single-digit mile trips spaced apart in the time dimension.

EVs have no problem "starting" in low temperatures. You might not be able to draw as much power for the drive train as the pack is heating up, but it's not a primordial "fuel-air-mix won't explode" problem.

There is no "problem" to get around; you either risk your battery pack getting damaged or you have an active battery management system that regulates the packs temperature. That will consume power, no way around it.

Now there are some conflating issues we have to consider. Tesla recently disabled in a patch the sleeping modes of some onboard components, and this vampire load might be contributing greatly to the large loss of energy reported overnight. The other is the drivers mentality; you don't drive it to the point of 5% remaining and then fuel up, thats how you do it with ICEs. Instead, you just simply plug it in whereever you can. And frankly, if you are going to keep it outside overnight at very very low temperatures (thereby forcing the battery management system to expend energy for heating), plug it into a 120V. They can (contra to your statement) get enough power from even from a 120V to keep the battery pack (and your range) at least at the same level, if not adding range.

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A side remark: I very much think this is a complete non-issue. 90% of driving is commuting, it is decidedly not long-range trips. And then this is mostly an issue of infrastructure; if there were at least 120V plugs at every parking lot, you wouldn't ever have to worry about these vampire loads. Infrastructure, since we are at it, is of course a much much bigger problem for gasoline cars; think of all the steps necessary to refine oil into gasoline and make it available at gas stations. Driving an ICE across states at the time of their advent would not have been a particularly enjoyable experience due to the general unavailability of fuel.

It's blown out of proportion for the normal use case, but I still think it was a very interesting review. I didn't expect them to be great road-tripping vehicles at this point, but was a bit disappointed by how the weather affected things. Even Musk's comments so far don't change my impression of that: so it's fine for a road trip if you make sure you don't get stuck in traffic, and make sure you never ever miss a chance to get it fully charged up, especially if the weather is cold? That's just not going to be competitive convenience-wise for long trips right now, no matter how much spin you want to put on it. The open question to me is just how fast the driver was going on the highway (90+ would make me raise an eyebrow or too), I'm not really sympathetic to the rest of Musk's claims at all. And unless he can provide some conclusive log evidence, collaborated by outside evidence, that's far more damning than what his comments so far describe, it reflects pretty poorly on the company to me. Much more poorly than the original review, since I expected that to be pretty much a worst-case scenario—and was very interested in just how well it would handle that kind of stress test.

Edit: the thing that really bugs me about the response is that it's empty so far. If you've got conclusive evidence, show the evidence. Don't go all he-said-she-said in the meantime.

I didn't buy his explanations when I saw him on CNBC and Bloomberg. The impression I got is that he's whitewashing the review, focusing on how fast he was driving and pointing to another NYT reporter who got 300 miles (and when the anchor pointed out that it was in different driving conditions, he sort of glossed over it).

Speaking of inconveniences, how can someone who lives in an apartment own a Tesla vehicle? Most parking garages I've come across don't even have a standard 110v outlet, let alone the 240v outlets needed for faster charging. Is the solution for them to hope that there's a supercharger near by? It seems like Tesla is only viable if you live in a house.

Increasingly seeing charging stations in multilevel carparks both in large apartment complexes and offices. I could charge a Tesla or shatever at work every day if i had to. Heck even The University of Alabama had EV charging stations.

Link to the Bloomberg and CNBC interviews:

http://www.bloomberg.com/video/musk-model-s-works-well-nyt-a...

http://www.cnbc.com/id/100439335

If you live in the Northeast, its a big deal. Give me a Prius or Volt any day.

> 90% of driving is commuting, it is decidedly not long-range trips.

Would you buy a second vehicle to accommodate your needs for the remaining 10% of your driving?

You could always rent a vehicle for your remaining driving needs. For 10% of total driving that might be somewhat impractical, but 10% sounds like a pretty high estimate for trips that would challenge the Model S's range. That's one long-range trip every week and a half. Yes, there are people who drive like that, but they are very much in the minority.

If you drive to grandma's/the in-laws/"up to the cabin" three or four times a year, that's only 1% of trips (assuming you commute every day and run local errands on the weekends). Most families in the US already have multiple vehicles. Why can't one be an electric?

ICEs are significantly less efficient at startup and until they get up to their normal operating temperatures. That's not so much a problem for long range trips, but taking multiple single-digit mile trips spaced apart in the time dimension.

Overblown, at least for modern cars. Girlfriend sometimes drives an ICE 1.5 miles to work, Gas mileage suffers ~30% versus freeway driving. When I did ~7 mile trips to work and back efficiency was <20% worse than freeway driving. Combustion chamber temps warm relatively quickly.

EVs have no problem "starting" in low temperatures. You might not be able to draw as much power for the drive train as the pack is heating up, but it's not a primordial "fuel-air-mix won't explode" problem.

In theory you're correct. In practice, ICEs will start and operate at temperature of -40F (perhaps with a bit of help heating the oil). The Tesla in the article was brought to its knees in temperatures within the positive teens.

And then this is mostly an issue of infrastructure; if there were at least 120V plugs at every parking lot, you wouldn't ever have to worry about these vampire loads.

Except now you have to convince everyone to install 120V plugs in parking lots, wire them up, figure out a way to bill for this or provided it for free, AND you have to remind the consumer to plug in every time they park their car.

The reviews from Tesla owners who have their own experience with the car in cold weather is interesting.

Can anyone tell me why the car discharges when plugged into a 120V supply? It's mentioned in one of the links above and in the NYT article.

I'm aware that you can't supply much current with a standard 120V supply, but why would it discharge? I would imagine at a minimum you'd have a very slow charge rate, but from these two anecdotes, it appears in cold weather it still slowly loses charge when plugged into 120V.

Is the car constantly heating the battery? I could see that being the issue as engine block heaters draw a ton of current and they take a long time to heat up an engine block. I'm assuming the battery has a lot more thermal mass than a 300 lb engine block.

It's not discharging because it's plugged into 120V. It's discharging faster from the cold than the 120V is charging, so there's a net loss.

I thought the cold caused batteries to slow down on discharge rate. The LiPo batteries I use for RC planes keep a charge much longer if they are refrigerated. They have a horrible discharge rate when cold though.

I speculate that it is a interaction of several things:

1) The current firmware assumes there is "unlimited" energy available when charging, so it can keep the battery warm with little impact on charging rate (this is not a bad assumption for everything other than 120V/15A charging).

2) The current firmware assumes that the battery needs to be kept warm when charging (this is not a bad assumption for everything other than 120V/15A charging, but may not be correct for low-power charging).

3) The power required to keep the battery warm in near-zero (Fahrenheit) temperatures is nearly the same as the maximum continuous power available from a 120V/15A outlet (1.44kW, because the maximum continuous load is only 80% of the maximum load), at least initially.

The firmware probably needs to be tweaked for cold-weather, low-power charging. The firmware needs to know how to estimate state of charge when the battery is colder than normal. It could probably prioritize charging ahead of heating until the battery reaches a higher state of charge.

Great thread. Thank you for linking it. My recurring thought as i read through it was of the iPhone first and second generation when battery life was pretty awful and you tended to carry a charger and nurse your phone through the day (much as with my first GSM cellphone). The iphone 4 had battery life to the point where you just didnt need to care any more (like my motorola razr).

Problem is, Tesla doesn't have moore's law to make the car run faster on the same charge or allow more empty space for bigger batteries, so the only real solution is more charging stations and faster charging.

To be pedantic, it is not that 120 V is not enough. It's that the amount of current you need at that voltage is prohibitive because of wire sizing, which is needed to minimize resistive voltage loss and dangerous wire overheating.

Absolutely right. I was using 120V as shorthand for "the 120V/20A circuit that we're all used to."

I don't think saying "120v isn't enough, you need to rewire your entire house" is really accurate either. Most water heaters, stoves, and some central heaters run off a merged breaker for 240v. You can easily use one of those lines for the car if you don't plan on taxing the thing the entire time (though I figure if you have 50k for a car you have 1k to add an extra circuit and wire your garage up for it).

Also, 240v cars makes so much more sense in a world where 99% of people use 240v outlets, and in the US you can just oscillate two 120v's and get a usually-good-enough 240v signal.

I don't think saying "120v isn't enough, you need to rewire your entire house" is really accurate either. Most water heaters, stoves, and some central heaters run off a merged breaker for 240v. You can easily use one of those lines for the car if you don't plan on taxing the thing the entire time (though I figure if you have 50k for a car you have 1k to add an extra circuit and wire your garage up for it).

Yes, although at least in my view part of the selling point is that we have plugs everywhere, so you have electricity anywhere right? Well, hunting around for a 240V plug is a big harder than 120V.

Also, even though 99% (???) of the world is on 240V, I think the current rating on those circuits still limits power to around 2kW sustained.

I'm in Australia, and our power supply is 230V AC (+/- 6%) (240V was the standard before 2000, but is still within the acceptable limits). Most power outlets are 10A (max ~2300W) but I also have two 15A sockets in my house for the air conditioners (3450W - I also use one to power my coffee machine, which pulls 3200W when warming up!), and could theoretically get a 20A socket (4600W) installed. With an industrial outlet, you can get single phase power of up to 32A (7360W), but I doubt most electricians would install that for you at a house.

Oddly enough, I've got a 32A socket hooked up to a water pump. I'm not entirely sure why the electrician installed in, there's no way the pump draws more than an ampere or two.

Thanks for explaining the 240/230v difference, I'd always wondered why it existed.

And some parts of EU still actually have 220V. There's no major practical difference between 220V/230V/240V, it's just that different parts of the world came up with slightly different standards. As standardization has progressed, now all of EU is on a nominal 230V ± 6% 50Hz -- in practice the countries are still supplying their old voltages. 230 is presently 220 in Hungary and 240 in UK. Since both are within the mandated 6%, this doesn't cause problems. Eventually, as parts of the grid are serviced and replaced, it will be transformed into unified 230V.

Also lot of electronics nowadays uses switched-mode supply so it doesn't really matter all that much.

Seriously? Which machine is that?

It's not that amazing. Any decent $60 kettle in the UK will do 3000W these days http://www.amazon.co.uk/s/ref=nb_sb_noss_2?&field-keywor... (viz. the electrical consumption surges during TV ad breaks http://news.ycombinator.com/item?id=5018560 ).

It's a used commercial 2 group machine. I got it for less than $1000 and it makes better coffee than the $2000-$3000 automatic domestic machines in the shops.

It is a little cumbersome though (had to plumb it to a tank, etc)

A bit like this one: http://www.cafeideas.com.au/product.asp?pID=3620&cID=211

Not bad! I'm after an espresso machine myself in Sydney. Never thought of looking for ex-commercial stuff.

I'm in Scandinavia, and our standard household circuit is 10A@230V for 2.3kW.

But when you need a lot of power, you would install a 400V three-phase circuit (230 V between one phase and ground, 400V between two phases), something like this: http://en.wikipedia.org/wiki/Industrial_and_multiphase_power...

This kind of circuit isn't very common in households, but it's fairly simple to get one if you need it - most houses have three-phase power right up to the door, so an electrician can install it in a few hours. My grandfather had one for his circular saw.

But yes, hunting for these circuits on a road trip will be harder than finding a household circuit. Although that could change rather quickly if electric cars prove popular.

> I'm in Scandinavia, and our standard household circuit is 10A@230V for 2.3kW.

Only 10A? That seems very low, the common "mainland" circuits seem pretty much all rated 16A (@230V). So you can't even run some electric kettles at your place?

(but I confirm you can get 3-phase for very high loads, you'll usually pay the electricity company through the nose for running it though)

I think the older standard was 10A circuits for most of the house, 16A for kitchen and washing room and a dedicated 20A for the electric stove. I thought 10A was the most common still, but I may be wrong there.

The standard for newer houses, the past 10-15 years or so, is indeed 16A. I have 5x16A + 1x20A and a 35A main circuit breaker, so I can pull about 8kW all together. Enough for a few kettles :) (This is for a a 40m^2/400 sq.ft. condo. A house would have more circuits and a larger main circuit breaker. And this is for Norway - we tend to follow similar standards as Denmark and Sweden, but there may be differences I'm not aware of.)

> I think the older standard was 10A circuits for most of the house

Ah that's probably it, I missed that you were talking about older houses. The content of your second paragraph sounds much like what I know.

In Australia 240v @10A is a atandard household circuit, and dryers etc. run on 240V 15A circuits. (I believe 400V is obtainable as per the GP but I haven't lived i Australia for a while.)

Netherlands mostly runs on 16A@230v wiring/breakers, coming to 3.6kW. At least for the last 20 years (kind of important for at-home lanparties :) )

Per Tesla's own charging estimates 110v/12A is good for about 5 miles/hour of charging. http://www.teslamotors.com/charging#/outlet

That's not particularly meaningful. 60 hours to a full 85kWh charge.

That would be fine for me, but my usage is not most people's usage.

It's fine for a moderate commute where you're driving less than 60 miles or so (assuming a 12 hour overnight charge). More so if you've got access to higher-output charging at another location. The case in the NY Times Tesla review is specifically for a long-range winter road trip, for which Superchargers are pretty much essential.