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> This is definitely well-planned

No, it isn't. First, Hawthorne has been a huge pain for owners. Lines waiting to charge. Second, there are several places which are mind-boggling as to why they "planned" it the way they did viz.: Philly to Pittsburgh you have to route through Baltimore and stop at Hagerstown in winter, then stop again at Somerset due to the massive elevation change. If Tesla had put a supercharger at Breezewood there'd be no problem. See the Tesla forum for complaints.

> that's 142 drivers per charger

This is a straw man. Few people will be charging at the Mitchell, SD supercharger. I chose Newark as an example because it is at a rest stop (contrast with others your have to go out of the way to get to) and it is right in the middle of a large metros. If you want to do the math on how many people will be stopping to charge there spending 30+ minutes each -- again, assuming you get the transformer to yourself -- I don't think it'll work out well.

I like Tesla because it is cool but I would never bother to alter my route or wait in line or do any of those things. Even if I only traveled 2-3 times a years. The reason is, if I buy a luxury/fun/toy car, it has to be a luxury/fun/toy, it cannot be a hassle. Waiting in lines and altering the route to charge is a hassle. I am glad others don't mind but even if I could afford it, until there is a better charging network or some kind of swappable battery thing or something else, I'll stick with hybrids or plain gasoline cars.

Yeah, you're definitely not in the Tesla demographic. When Consumer Reports dropped Tesla from the recommended list due to the number of repairs needed, they noted that an astonishing 97% of Tesla owners would buy another one... despite all the hassles.

That says a lot about people who buy Teslas.

Well for one, I can't afford it, so realistically I am not in the demographic. But if I could afford it, I would want it to be less hassle. Besides that I am really excited for it, well heck, for any tech Elon builds.

Day-to-day, it's less hassle to charge in your garage every night than have to visit a gas station once a week. It's only long trips where it's more hassle. Current Tesla buyers are people who think that decision is a slam-dunk. It's safe to say that there are some number of similar fanatics in the lower price band of the Model 3.

Or it says a lot about the experience of driving a Tesla compared to a gas car.

Re: Hawthorne, I acknowledge it's not perfect and there will be kinks. And they'll get fixed. Just as the iPhone had imperfections, and they got worked out. Remember hearing people complain how you couldn't run multiple apps at once, a few years ago? Then that faded away, and sales were never slowed.

I'm sure you're right, some areas will end up overburdened-- and they'll fix it.

It takes me 5 minutes to put gas in my car. It takes 40 minutes to quick charge a Tesla (longer for other EVs)

Also when analyzing scarcity of chargers you should look at popular travel routes, not population distribution.

I'm not saying you're wrong, but your analysis is weak in those points.

Disclaimer: I work for a competing car company, any opinions are solely my own.

Am I the only one who dreads going to the gas station and runs the car down to the absolute empty point before getting gas? I really don't ever want to go to a gas station again and would rarely use the supercharger network.

I don't dread it so much any more. Gas stations have gotten a LOT better in the past 5 years or so, at least here in the South. We've got Sheetz and Wawa, which are actually pretty nice to pull into. Everything's generally new, there's lots and lots of pumps, and if you need to use the bathroom or want to buy some snacks, the bathrooms are usually nice and clean and the food selection is pretty good for a quick-stop place. The newest ones even have made-to-order sandwiches and other lunch food.

It's a huge difference from 20 years ago when gas stations were nasty, dingy places with the worst bathrooms in the world.

It's not as good in the Northeast, however. Most of the gas stations up there tend to be small and pretty crappy.

There is a range of options nowadays. I think that the portion of liquid fuel only options will decrease over time, and the mix of PHEVs will increase sharply in the very near future.

I think electric only makes a lot of sense for many applications, but certainly not all.

Anyway, my points above were related to Supercharger congestion in holiday seasons - something that will be even crazier in the Chinese market with the Lunar New Year.

I bring up China because they are the largest car market, and the Chinese govt is pushing for fuel efficiency and pollution reduction, both of which electric cars achieve.

Dreads? That seems to me to be a overly strong reaction. Though if an EV meets your driving needs and you're able to charge it at home, etc. I can certainly see the appeal of not needing to bother with it.

Why do you dread going to the gas station?

If it took me an hour to fill the tank - absolutely. It takes me less than 5 minutes and I often still have to wait in line if I'm forced to fill up on the way to, or way home from work.

But you never hit the Supercharger on your way to and from work, because you charge at home. You only need Superchargers on long trips. Most people will visit them only a few times a year, so the demand is much lower.

Right, BUT - everyone tends to make those long trips at the same time. Thanksgiving, Mother's Day, Spring Break, Easter, Passover.

Most of those trips aren't that long. The average Thanksgiving trip is a bit over 200 miles, for example:

http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/pub...

Maybe 40% of gas cars will need to stop for fuel during a trip of that length, assuming a range of 500 miles and refueling when near empty. EVs should be able to make it directly, since they'll start at 100%.

You're absolutely right that the network needs to be sized for peak demand much higher than average demand, but even then I think it's less than what you'd need for the same number of gas cars.

Why do you assume you're starting at 100%? That doesn't seem like a given to me. You go to work on Wednesday, maybe run a couple of errands, and then leave on your Thanksgiving drive. It's nightime in November so you need the heat and the headlights. There are no superchargers within 50 miles of your planned route. Now what?

Yes, in that scenario you'd have to stop. But then gas station usage goes up too. There's some crossover point where the EVs need more, but I don't think this gets you there.

By the way, don't mention headlights. Their power consumption is absolutely negligible. Heat, for sure, but not lights.

Headlight consumption is "absolutely negligible"? I've measured D2S headlight consumption at about 3A, or 6A for a pair; roughly 50W total, and it's constant. While I'm sure that's a lot less than you're using for propulsion or heat, that still doesn't seem quite "negligible". Of course, the on-board computer in the Tesla, plus its giant LCD screen and backlight, probably use at least that much continuously.

Yes, negligible. Cruising on the highway uses about 20kW. 50W total is 0.25% of that. If you drive for three hours, the total energy consumption of the headlights during that time would be enough to move your car another half mile. Minor stuff like the precise air pressure in your tires, minor variations in wind, or different road surfaces will have a much bigger effect.

Put it another way: if you somehow convinced the car to leave the headlights on permanently, and you weren't plugged in, the headlights by themselves would take nearly two months to drain a 60kWh traction battery from 100%.

It's pretty amazing how much energy capacity they're able to put in that battery pack. 60kWh could run a clothesdryer for roughly 20 hours straight.

Out of curiosity, what's the "sweet spot" for efficiency for a Tesla? I imagine modern highway speeds aren't the best because of wind resistance. I wonder what the energy consumption is at, say, 45mph. Would you be able to extend the range significantly that way?

It is pretty amazing. Note that Tesla doesn't even sell the 60 anymore, their current low end is 70kWh, and the high end is 90kWh. (A 100kWh will probably be introduced pretty soon, based on leaked info from the firmware.) The Model 3 will probably have a smaller battery, as it won't need as much, and that will save cost. 60 seems like a decent bet, although it might be as small as 50 or 55.

On the other hand, it's an amazingly small amount of energy. A 90kWh battery holds the equivalent energy of 2.7 gallons of gasoline. It's just that the electric drivetrain is 90+% efficient at turning that into motion.

The optimal speed for maximum range is about 25MPH. The slower you go, the less energy you waste fighting air resistance. I assume that below that speed, the energy that goes into maintaining the various systems start to cancel out the gains from going slower. The current record for a Model S is 452.8 miles, which took almost 20 hours. Not exactly practical.

Slowing down more reasonable amounts definitely helps. According to Tesla's range calculator, with a 70F outside temperature and no climate control, a 90D can expect to go 275 miles at 70MPH on level ground. Drop to 65MPH and you can get 302 miles. At 60MPH, the range is 332 miles.

This is always good to keep in mind on longer trips. You can watch your projected state of charge on arrival, and if it starts to drop below where you're comfortable, just slow down a little bit and that should solve the problem. Obviously, it's best if you don't have to do this, but it's a good plan B or plan C to keep in your pocket.

>On the other hand, it's an amazingly small amount of energy. A 90kWh battery holds the equivalent energy of 2.7 gallons of gasoline.

The only problem with that kind of comparison is that the energy in combustible liquids isn't actually usable for propulsion like that. There's no way (that we know of yet) to turn 90+% of the energy in gasoline into propulsion; most of it is just going to be wasted as heat due to the Carnot Cycle. Of course, if your goal is to simply produce heat (like for heating a building), fossil fuels are pretty effective at that.

Gasoline-powered fuel cells might do somewhat better than regular ICEs, but still nowhere near 90+%. In a nutshell, electricity is by far the most efficient form of energy transfer we've found so far. Everything else ends up wasting lots of energy to heat any time it's converted from one form to another, but a good electric motor can convert electric energy to mechanical energy with 98% efficiency (and vice-versa, with generators).

I wouldn't say it's a problem with that comparison so much as the point of it: it illustrates the relative efficiency of the two.

It also illustrates some side issues, like why an EV will suffer significant range loss when you need a lot of heat, while a normal car doesn't care.

You could always just rent a regular gas car for those long trips. Or just take an airplane or Amtrak or a coach.

But they know this, and will keep ahead of that demand. Thanksgiving 2018 is a long time away, and building more superchargers is the least of their engineering problems. Very easy to do.

And I think you're not grasping how small a number 142 is for a full-fledged gas station.

There are over 200 million people in the US with driver's licenses, and over 114,000 gas stations. If only half of those people are driving, that's almost 900 drivers per gas station.

142 is nothing! Particularly since this isn't accounting for the fact that many/most Tesla owners fill up at home. The competition for charging space you're anticipating is simply an imagined worry.

Sure, but you get that the whole distribution model is different, right? Gas stations accept everyone who has a gas-powered vehicle, and take 5-10 minutes to fill up.

Supercharger stations accept people who are on long trips and take 40-something minutes to fill up at best case.

So it's reasonable to say that the usage patterns are totally different.