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Comment by thomascgalvin | Hacker News Reader

Completely anecdotal, but I rented a Tesla when I was on a business trip a couple of weeks ago. I only had to charge it once over the entire week, but to do so I needed to park in front of a charging station for about an hour, and I was parked next to three other people, also charging their vehicles for about an hour.

I understand that most people would (ideally) be charging up at home overnight, but the logistics of taking a long trip are, if not daunting, at least very different from today's "pull into a gas station, fill up, hit the restroom, and get back on your way in fifteen minutes."

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Was that a supercharger or L2 AC?

If a supercharger the car needs to do a way better job letting you know the charge after 80% is far, far slower and just not worth it. You'd be way better off doing 2 different charge sessions, both from deeper state of discharge. Your total time would have been less than half. If you're on a multi-stop trip with Tesla's charge curve you're actually better off stopping around 50-60% and heading off to the next charger.

I have road tripped my tesla 1000s of km and only once have I ever stayed at a supercharger more than 30 minutes. That was -15C in a snowstorm with a large gap to the next charger and I have the small battery model 3. On 8-9 hour drives I only add about 40 minutes of total charging time. When combined with the necessary bathroom and food breaks the car is pretty much always ready before I am.

If it was L2, then the rule is ABC, always be charging. Sometimes you can't avoid hanging around since L2 isn't that fast, but most of the time you should practice pro-active charging and just grab a little juice any time you get the chance. That's harder when you don't have driveway charging, but it's going to get easier and easier as more infrastructure gets built out.

All this information needs to be far better presented to drivers, especially ones new to EVs. Gas pumps don't get slower the closer to full you are whereas battery charging varies greatly based on state of charge. There is a learning curve and manufacturers are not doing enough to teach their owners (likely for fear of scaring them away)

> Gas pumps don't get slower the closer to full you are

Actually (and pedantically) some here do. Just as you approach full they will drop back to a slower pumping speed for the last few drops.

Right, for the final few ml / seconds. Common battery chemistry drops from top speed somewhere between 30-50% state of charge and steady decreases until 80% where it falls off a cliff. Different charge curves vary, but that's pretty typical. Vastly different experiences.

> I understand that most people would (ideally) be charging up at home overnight,

50% people in EU are living in apartments. In Eastern Europe apartments were built 3:1 - 3 apartments per 1 parking space. It is very difficult to park there, it is impossible to park where you would like to.

Some people who are living in older houses (19th, early 20th century) does not have drive way nor garage, because it was not needed at that time.

It is never going to be "most" who are overnight charging. It is a niche feature for few rich.

Charging requires running a standard 240VAC connection to a pole or wall near the car. It is not a complex or luxurious technology. Yes, that wiring doesn’t exist today and will have to be built out, but wiring conduits already exist in most cities for street lighting and residential distribution.

What’s actually somewhat complex and luxurious is the parking space itself: as you point out, cities and towns don’t build/maintain enough public parking spaces for the entire population because setting aside land and maintaining public areas for the sole purpose of car storage is expensive. Once you’ve committed to that investment, running wires to your expensive parking spaces is a relatively small comparative investment, and it’s one that actually pays for itself if cities add a modest surcharge to the electricity cost.

> Yes, that wiring doesn’t exist today and will have to be built out, but wiring conduits already exist in most cities for street lighting and residential distribution.

That's easily said than done. You can't build it wide enough, because maintenance and upkeep (you need to pay for reserved power) for big system will eat you alive. And if you build it small so maintenance and upkeep is as smallest fraction of revenue as possible, it won't make a difference for a comfort of BEV drivers compared to today.

And all of that is under assumption that your local substation has spare power. And that's usually not the case.

I think people hugely underestimate the cost of maintaining parking spaces on public streets in dense urban areas, and then wildly overestimate the costs of the EV charging infrastructure drivers will need. You have to set aside enough valuable and productive urban real-estate to store a 1+-ton vehicle at street level, grade and pave the space for it, pave and maintain every piece of street that leads up to it, and then police and clean the streets (to keep people from blocking it in or parking illegally or starting fires with unmaintained vehicles.)

We tend to think of street parking as “free” or “cheap” but that’s just because we pretend that asphalt and pavement and public land falls from the sky, rather than being a massive expense that taxpayers have born and continue to pay for. There are some good articles (mostly US focused) that talk about the replacement cost per-household of rebuilding new parking in even land-rich cities and the cost is staggering, close to $100k per household even in Wyoming. (It is hard for me to believe that these costs are lower for historically-preserved dense European cities.) Compared to these sunk costs, running 240V wiring for the equivalent of several new households per block doesn’t seem like a massive investment. The ongoing maintenance costs will certainly not exceed the cost of street maintenance.

As far as how much power we need: the average European driver travels 32.9km/day. At a (Tesla) usage of 166wH/km that’s 5.461kWh/day, or 273W continuous average power draw assuming most people drive for 4H/day and park the rest of the time. You’re absolutely correct that even this level of new consumption is going to require us to upgrade city grids and substations, but that’s already baked into the EV transition. We’ll have to upgrade substations even if everyone stores their cars in private garages off the street.

58% of Americans live in a household with a garage or carport. So already "most" Americans can install easy access to overnight charging.

Most hotels I've stayed at recently had charger setups. Did this one not?

This sounds like a problem of your unfamiliarity with the area. There were probably multiple places to charge, but because you didn't live there, you didn't know where to go.

That sounds like a problem that will work itself out. Right now there are gas stations on every corner because we spent a century building gas stations on every corner, and you know what to expect from them. The similar infrastructure for cars is brand new.

Perhaps the place you were is even further behind than some. But if your trip had been to my town, I could name you a dozen places to go charge up: the shopping center, several grocery stores, most gas stations. And I'm not an electric car owner; I'm just somebody who lives here. There are always free spots at all of them.

Yes, the rent-a-car scenario is very different from the home ownership scenario. If you're renting a Tesla, the easiest way to make it work is to make sure that your hotel has on-site EV charging. If you can charge at the hotel then it doesn't matter whether it takes one hour or even eight hours to charge.

Even hotels that do have charging stations don't typically have nearly enough to park, plug, and forget. EV for commute when you have a garage with descent charger is great idea. EV as a rental is absolutely impractical, especially when one is traveling for business and has no time to monkey around

Maybe in California, but here on the east coast I've never seen anyone but me use them. You absolutely can plug in overnight.

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