Unusual charging on a 5,000 mile electric car road trip


Rounding out my 3 part series on doing a 5,000 mile international road trip in a Tesla, I talk about the times I used slower chargers. The world installed vast numbers of slow chargers at huge expense in a giant waste of money, but they do have virtues on a road trip, and eventually all hotels will have them. On a road trip charge and range become very important and sometimes they save the day.

See the story and analysis at: Unusual charging on a 5,000 mile electric car road trip


An interesting view of this subject from a US perspective.

I would add leisure facilities (movie theatres, gyms, etc) to places where there should be a row of 50-100kW DC chargers for those who can't charge at home or work.

If you can't charge at home or work, yes you will seek places you stop for 30-60 minutes. Movies usually mean a 2 hour stop (does anybody even go to those any more?) which is too long for 50kw chargers, but you can design them to let 2-3 cars plug in and charge in sequence if you want to go there. Problem is movie theatres are mostly popular at night. The ideal location of a charger will see use all day long, and for that, grocery stores are the obvious win. People go to them regularly, they drive, and they spend 30 minutes but not more than an hour. Gyms might be a decent choice though usually people spend an hour there, which is a bit too long.

A key error many make is they presume people want a "full" charge. Nobody ever does a full 0 to 100% charge, a full charge is actually from 20% to 80%, or about 35kwh or less on a city car. But normally you don't want to let it get down to 20 if you can't charge at home or work, so you may want more like 20-25kwh. Which is under 30 minutes on a 50kw charger if it can do full rate.

It's OK if you don't have to unplug your car as soon as it's done. Most fast chargers are designed to require that, but future ones can and should be designed with extra cords so you don't have to do that.

Do people go to grocery stores any more?

Will this still be true in 5 years?

While of course people will use things like Starship delivery and much more, I think they will still shop and take car trips to places of all sorts. We're a long way from using the car only to commute in the day. Maybe where we go will change but wherever we go for 30 minutes or more will be a good place to put fast charging for the people who can't charge at home.

Personally, I've been in a grocery store maybe five times since the start of the pandemic. But I'm probably an outlier there.

Curbside pickup is great, though.

Yes, me too, and many others, but it's changing back now and the stores are full. Commuter/office lots are of course the best place for daytime charging, but for cars that don't commute and can't charge at home, you just find out where those cars are going for 30 minute stops. Of course restaurants are an answer but everybody can't charge at dinner time (a terrible time to charge.) If there is nowhere else, those people will face having to make deliberate charging trips. Not ideal. They may not be good candidates for EVs, at least today. Or they can use swap, though other people don't need it.

Significant expense with a very unclear payoff for all but the biggest shopping locations to install a charging location.

Installing a spot at work or at home is a lot more likely to pay off. You can install a slower charger, and have it dedicated to a certain person, or a faster one, and share it between multiple people. But you can have the people in mind before you install, unlike the grocery scenario.

Obviously -- and I have always said so -- charging, around 3kw, at homes and work parking lots is the ideal.

But we are left with the people who can't charge at home or work. We try to reduce the number but there will still be plenty. For them, they need to charge somewhere. Ideally it's somewhere they already stop, like stores. The alternative for them (other than gasoline) is deliberate stops of 20-30 minutes about every week, or battery swap. (This would be supplemented with slower and cheaper 7kw charges at more random locations they stop as these are cheaper than 150kw DC chargers by a huge margin.)

So this experience is of course an inferior one. If we want to tell everybody they must electrify, we want to not have to give these people this inferior experience, as it makes it harder to have that happen.

My approach would be to add the externalities to the cost of gasoline and let financial pressure convince these folks to either put up with the inconvenience, or pay the premium price for expensive charging at the places they go. However, in the current regime, instead the plans are to just require that no new cars be ICE cars, and that means you want to get them an option other than driving an old car.

I guess the main disconnect I have here is that I don't want to tell everybody they must electrify. If it doesn't make sense for them, then they shouldn't do it. Forcing everyone to go 100% electric no matter how much of a PITA it will be is stupid. We should not be so all-or-nothing and black-and-white about things. At some cost, it is better to just use a hybrid and call it a day.

With that said, in most cases the best solution for the people who can't charge at home or work is to install a charger for them at home or at work, not to install one for them at some grocery store parking lot. I'm really not sure what type of situation one could be in where it isn't feasible to do this. Presumably they have electricity near their home or work, if not both.

A fast charger at a grocery store might make sense, if it's conveniently located for people who need to occasionally charge significantly more than they can charge at home or work (or hotel or other temporary sleeping location). They should expect to pay significantly more for that situation, though, as the provider necessarily needs to overbuild to handle the peak demand, not the average demand. They definitely shouldn't expect it to be free. That just doesn't make any sense.

Charging at work requires the cooperation of the employer.

I have a garage at home, but it is not next to the house, Ithere is no electricity in it, and I can’t run a cable to it (because of traffic; it’s a private street, but still). For people who live in apartments that is a real issue.

Grocery stores offer it because it attracts new customers. Presumably the additional profit offsets the costs, otherwise they wouldn’t do it.

It’s like the prisoner’s dilemma: whatever the competition does, you are better off offering it (assuming, as is apparently the case, that the increased profits more than offset the costs as long as one offers it and not everyone else does), but if all grocery stores offer it, then they are worse off than if none offered it.

Yes, the employer or operator of the commuter lot has to participate. It's very likely there will be government incentives to do so -- after all, this is the best way to do it and right now the governments are keen to spend money on this.

However, it's not needed. The power companies want cars plugged in that they can control the charge schedule of. When they have surplus power, they want to sell it to those cars. This will be especially true in a renewable grid, with a big solar surplus from 9am to 2pm. They need to sell all that power, and so they will pay for the charging.

Your situation at home is unusual. Most people can get power in their garage. However, you could also run an extension cord for 230v15a and that's all you need at home, at least in most situations the parking space is within range of a plug. For you the cost may be not worth it.

Charging at work requires the permission of the employer (or whoever owns the land where you park for work). Charging at the grocery store requires the permission of the grocery store owner (or whoever owns the land where you park for shopping). Charging at the garage near your house requires probably the permission of your electric company, who no doubt has an easement to cross the road. Alternatively, you could get the permission of the government that manages the road, or the apartment owner who own the land.

Any way you do it, you need someone’s permission. Why not build the charger in the best location and then get that permission?

You say grocery stores do it because it attracts new customers. What I say is that grocery stores generally don’t do it because it generally doesn’t attract enough customers to justify the expense.

It’s not a prisoners dilemma. If building a charging station at a grocery store made economic sense, the grocery store could do it and charge for it, and they’d break even or make a profit.

But a grocery store isn’t a very good place to put a charging station compared to others like the workplace or the home.

Whether one approves of this much government involvement or not, there is a large government effort declaring improving EV infrastructure a vital public goal to be pushed with regulation and subsidies. It is very likely they will screw it up, they did in the first wave.

Accepting that, it's best the government pressures put charging where it's useful and economical -- where cars park for longer periods for most charging, a bit where they frequently go for 30-60 minutes. As such I suspect employers and apartment owners will or should get pressures to install there.

The challenge is that public charging isn't a useful business. As I have written, if most people can get gas at home or work for $1/gallon (or free as an employee perk) while they work or sleep, what's the business of selling it for $4/gallon at a pump that takes 5 minutes/gallon in a public space? You will be the last choice.

One answer would be to say, "If you can't charge easily, an EV is not for you" but that doesn't work if you also ban ICE cars, unless you are willing to tell too many voters, sorry, a car is not for you.

I don’t think it makes any sense to ban ICE cars any time soon, so that’s really a non-issue. But I think Tesla has shown that there is a market for selling charging at the equivalent of $8/gallon. Yes, most people can charge at work or at home much more cheaply most of the time (though not as cheaply as it looks if you ignore the costs of installation and maintenance). But not everyone all of the time.

In the longer term, yes, we’re going to start forcing people to drive electric cars if they want to drive at all, and many of them won’t have access to cheap charging at their home or apartment. But even then, it’s better for governments to subsidize the building of charging stations where those people work and sleep (specifically where they park to work and to sleep), than it is for governments to subsidize charging at places like supermarkets. I’ve joked before about whether or not people even go to supermarkets any more, but on the time scales we’re talking about to ban ICE cars I don’t think it’s at all unreasonable to foresee a world where people don’t park at supermarkets. Between delivery and curbside pickup and taxi services that can serve other people while you shop, parking at supermarkets is going to drastically shrink in the coming decades.

I think charging where people park at home makes the most sense. And I don’t just mean garages. It probably makes even more sense on the streets or in driveways. Even when and if we move to a world where most traffic is robotaxis, it’ll still make sense for most of those robotaxis to park in residential neighborhoods overnight, when demand for the cars is low, and when they are going to need to be in those residential areas in the morning anyway. If you have a charging station on the street, you can adapt it to let the robots charge from the street. If you have a charging station in the driveway, you can lease your driveway to a robotaxi company who can use it for charging. Both at night and even potentially during the day. That lease might even be paid with credits for using the service. I really think charging in residential neighborhoods makes the most sense. Regardless of whether people own or rent. Regardless of whether people have driveways. About the only exception would be large cities where people don’t have cars parked where they sleep.

For much the same reasons, I think places where people work is second best. We probably are going to move to working from home in the next few decades, though I believe this won’t be nearly as drastic of a change as some others suspect. And demand for cars during work hours, while not as low as overnight, is not as high as rush hour. So having some robotaxis parked at these locations charging during the day would probably be convenient.

Granted, this is decades away, so it’s not too important to entirely plan for it now. But I’d be very careful before subsidizing building out infrastructure in places like grocery store parking lots.

(Maybe in the even longer term future, the very structure of our residential neighborhoods will change. But I think that’s fairly unpredictable at this point, and far enough in the future that we can worry more about that when the time gets closer.)

I am not sure we need subsidy for any of it, though the people who can't charge at work/home are the most likely to need some assistance, and it would come as part of the state agenda of facilitating the transition and the ending of the selling of ICE cars. ICE cars will remain on the road and available for decades after that of course, but such a law is still a burden on those who can't charge at home/work.

How much is charging at home? Many people can charge at home with no install cost required. I did just fine on a 20a 115v plug which gives me 70 miles of range each night for a long time. It's not care-free to use level 1 but it works. Install at level 2 comes at a wide range of costs, often just a few hundred dollars though sometimes much more. Level 1.5 -- 240v at 15 amps for example -- is pretty care-free and can usually be put in using existing 12AWG wiring by rewiring the socket and the breaker to switch a dedicated 120v circuit if you have one to be 240v. No new wires, so fairly low cost.

Driveways are easy (if next to the house where a plug is.) Streets are a bunch more costly but are the only at-home option in certain city blocks with no driveways.

For the robots wanting to charge at night, one obvious choice is the office parking lots of the offices that are near the residential areas. About 1/3rd of a mile from my home is a parking lot with 72 Level 2 chargers that sit idle every night at the Apple building. My needs would be met fine if my car were able to wake up at night and drive there on the empty night-time streets and plug itself in. (It and the station would need adaptations to let the car plug itself in, or you could have a plug jockey in a station that large.)

The apple chargers are free (even for the public) but shot down at 7pm. If made open at night, they would stop being free, and probably would be more expensive than my home charger, though. In the day they are "using" the vast array of solar at Apple, which is a presage of the future. Not everybody lives next door to Apple, but there are commercial buildings usually within short distances in most residential areas.

Charging at night in office complexes can work once you have autonomous vehicles that can plug themselves in, but it’s almost surely less efficient than charging in residential neighborhoods. Why move the vehicles around when you can just charge them right where you’re likely to need them next? You don’t even have to automate plugging them in if you can get the home owner to do it.

Bringing power to streets is generally more costly than driveways or garages, but bringing power to outdoor parking lots isn’t cheap either.

I don’t know of many people who mainly use level 1 at home. Yeah, it’s possible, but most people aren’t that cheap.

Yes, it is better if the charging is closer to where the vehicle wants to live. But if it's sitting idle a mile away that's cheaper than building it close, especially while waiting for demand to justify making more.

It's also workable as a supplement for Level 1. Level 1 is good enough almost every night for the average car. However, there are these odd nights when you drive a lot two or three days in a row, and you want a bit more than level 1 will give. So you either stop at a fast charger -- or have your car run off to an office park at night if one is around.

I suspect there are more people on Level 1 than you think. It really does work pretty well. I used 20 amp level 1 for 2 years and only once did I visit a supercharger to supplement it. I am below average miles/day but not that far below average. But a large bunch of people are below average.

You seem to believe that building a charger at an office is cheaper than building one at a home. I think putting a charger at an office location tends to be more expensive, if anything, and only rarely is it less expensive.

If people are okay with level 1, even moreso. But as you point out, sometimes level 1 is not enough, and for most people it’s worth spending the money to not have to deal with that.

When (and if?) robocars become ubiquitous, that might change the convenience factor. It’s not clear if electric cars will become ubiquitous before robocars, though, and just because you have a robocar that doesn’t mean it can charge itself. And even if it can, a charging spot in a residential neighborhood might make more sense than one in an office location, especially if we’re moving toward a model where cars don’t need to stay parked at the office all day during the work week.

As we move to the robotaxi model, the size of office parking lots will shrink. The number of driveways and street parking spots will also shrink, but probably over a much longer period of time. It’s easier to put up a building where a parking lot used to exist than it is to redesign residential parking infrastructure.

So the only real barrier to building charging locations near residences is zoning laws. Hopefully state (or maybe federal) governments can ensure that zoning laws don’t prevent it from happening.

No, I don't think office is cheaper than home. Or rather, it's a mix. At some homes it's very cheap to install charging. At others it's very expensive -- $5000 to put in one station if you need to replace your power panel. Offices will be in the middle.

A car like a Tesla could, even today, be able to crawl off on its own at night on slow streets to a charging station a mile away. I would not trust it to drive the real streets in the day, but I can see it getting to that level. It would go very slow (as is only acceptable at night) and Tesla would have to accept it might want a map of the route. Of course it needs a way to plug in a the station, either a pump jockey or robotic plug arm. The latter exist but are not in wide manufacture.

So that comes first, if we wish it or need it.

Night charging of course easily re-uses commercial parking which sits unused. As I have said, I think by 2030 we'll have a lot more solar which makes us want more day charging.

Where I charge, the charger is nominally 50 kW, though I usually get about 35. I spend about an hour in the grocery store. That gives me about 35 kW, or about 60% of my Tesla battery (long range +), which appears to be effectively 55 kWh. So I charge from 20 to 80 per cent or whatever. 80 per cent is good for about 300 km (200 miles). Charging twice a week (I’ve gone shopping twice a week for decades, long before Tesla even existed) is all I need.

When on long trips, I charge at the Tesla superchargers. Sometimes I have to hurry back (after eating, say) so that I am back before it is full.

These days, I think that the main hurdle to going electric is neither price nor range nor image, but rather the complicated payment systems. Tesla solved this correctly. Without a Tesla, one needs various cards, online accounts, apps, and so on. I never understood why one can’t just pay with a credit card. Petrol stations with no attendants, with payment by card, have been around in Scandinavia for decades. Recently, a law was passed in Germany requiring all new charging stations to offer credit-card payment. I think that that is a good idea. The motivation for not doing so was that companies want to get customers locked into their network, which reduces competeition. (Note also that Tesla offered its system, which was ready to go before any other large network, for free, but other vendors didn’t take them up.

Yes, it is annoying that after Tesla showed how it's done, everybody else screwed it up. The most common problem with charging at ccs stations is not them being broken, it's billing issues.

There is, however, a data protocol now in place over ccs and chademo (and even 1772) to negotiate payment. A few cars support it. However, it does require you have some sort of account with the network provider. Everybody hopes to be the network of networks. And you also need to make sure the person has agreed to the price.

I have proposed to the network operators that they start charging immediately, even before the person has provided payment info or credit cards. Give them a few minutes to work out payment. Shut it down if they don't pay after those few minutes. (Hell, in much of the world you don't pay for gas until after you pump all the gas.)

Minimal risk to the station, but now the fiddling with payment loses no charging time.

Credit card is fine, and ideally you can provide your credit card info over plug-and-charge protocol.

I don’t know how common it is to have a garage without electricity AND not near the house. It’s less than a minute away, and not too far to run a cable, but that would be across a (private) street where there is some traffic. It’s probably more common in Europe, as are people who live in apartments and park somewhere on the street.

Right now, as long as the supermarket charging works, I don’t need it. I think we’ll probably get electricity in the garages, or some other solution, before I need it.

I don’t know how common it is to have a garage without electricity AND not near the house. It’s less than a minute away, and not too far to run a cable, but that would be across a (private) street where there is some traffic. It’s probably more common in Europe, as are people who live in apartments and park somewhere on the street.

Right now, as long as the supermarket charging works, I don’t need it. I think we’ll probably get electricity in the garages, or some other solution, before I need it.

You might be able to run the wires overhead. Burying is expensive. But for now we will class you as one of those who can't charge at home. For the vast majority of people in the long term, charging will be at home or work, but not for everybody, which is why solutions like the grocery store are needed. It's not quite as nice as at home, where you are full every night without much thinking about it, but if your trips to the stores with charging are frequent, and the chargers there don't fill up and are conveniently located, it should be just fine.

One thing I have worried about with charging at public stations is that today it works because not that many people do it. On my recent CHAdeMO trip, there were many stations I went to where only 1 or 2 chargers were present, and no other charger for many km. They were almost always empty -- too empty in fact -- even as thousands of cars with benzin whisked by. It won't take much more demand before you start showing up to find them full with somebody waiting. Obviously time to build more, but that will be slow and those building won't want to overprovision again.

I think having chargers usually be empty is in the nature of how long it takes to charge. Charging goes along with parking, so you shouldn’t expect more usage than that, and it’s necessarily much less because you can’t match the need for parking and the need for charging perfectly. You’re probably never going to get to the level of infrastructure efficiency of a gas station unless you have five minute supercharging. But that’s okay, because electricity is much cheaper per mile than gas\diesel, so you can save enough there to make up for the overhead, as long as you charge enough of a premium over your electricity costs.

Charging slowly at home, if you can easily run electricity to a place where you park, is probably going to always be the cheapest by far. Charging a little more quickly at home in a garage which is close to your breaker box can also be a good deal in the long run. Charging at work is probably also not too bad. If you park outdoors you have to build a charger that can withstand the elements. But you don’t need to spend much on integrating a payment system into the charger. Just putting a passcode on it is probably enough. Or you could forgo even that and just have an on/off switch somewhere in the building. Ditto with installing something outdoors near your house.

It won’t be cheap in terms of upfront costs. But you’re saving the planet, so it’s worth it, right?

Charging at work should be the win, because that can be done with solar. Solar is now the cheapest power you can build, and getting cheaper. Solar erected in the parking lot has no transmission cost which makes it even cheaper. Like 1 cent/kwh compared to 10 cents at home. Solar only comes during the daytime, which matches charging at work. When it's raining you buy grid power at the higher price, and when nobody is parked (Saturday) you sell it to the grid. Charging batteries is the most ideal load for solar power. Your net price won't be 1 cent/kwh because of the need to buy power on the rainy days, but it will still be cheaper than anywhere else. That's why it will be a free employee perk in many cases -- who is going to bill employees for 30 cents of power a day?

In fact it will greatly annoy those who don't drive a car to work that they can't get this. Well, to the tune of $500/year which is why they pay for electricity if they charge at home.

Charging at work can work. Yes, it matches up well with timing for solar. On the other hand, it’s almost always going to be more expensive upfront compared to residential installation. And unless you work in a location that is particularly ideal, it’s only useful for 5/7 of the week (even less with vacations/holidays/etc.). The other two days you have the equipment sitting there idle, and you also have to sell the electricity to the grid at what is probably not going to be a great rate. So it’s not perfect. But I agree that it’s one of the most effective places to install charging. Probably second behind at the home.

Billing employees 30 cents a day would be dumb (especially if that only covers the electricity!). Billing them $500/year, to cover equipment and electricity, no matter how much they use, might not. (The charge could cover exclusive access to one spot, one day a week access to a much faster charging station, or could even be a more complicated points system if you have enough employees interested to make that worthwhile.

If the alternative is to not have charging at work, it might be worth it for some people, especially if it means they don’t need to have charging at home (which might be quite expensive for some people).

Why annoy people who don’t drive a car to work? Let people who get the benefit pay for it.

I agree, it could be reasonable to bill them an annual or monthly fee and have it cover all costs. And indeed more fair, because those who do not need it would not pay it, including even those with even cheaper charging at home.

However, offices tend to like giving perks of this level away. I mean $2/day as you suggest is on par with the coffee and drinks found in any office, and far below the food found in many. Or the parking in places it's hard to find parking or many others. At least during the era where companies want to say, "look how green we are, aren't we great" it's a relatively cheap way to do that.

And the solar panels put over the parking lot also provide power to the office or to be sold to the grid, which covers many of the costs of their install. In fact, many companies will do that anyway, since offices are good solar customers, wanting their power mostly during daylight hours.

What places are giving away significant amounts of food for free? IRS regulations are pretty strict on that, as they are with giving away free charging.

It’s not necessarily green to give people an incentive to charge at work as opposed to at home.

They should just charge for it. And I think most will. And assuming they do, people will tend to only charge at work if it is better than charging at home or somewhere else. Let the free market decide what’s best.

And if they really want to give it away for free, offer a $500/yr (or whatever the cost is) bonus for people who instead charge at home. Let the free market decide what’s best.

Employee perks don't run by free market principles. Or rather they use them in a very high level way, in that they help recruit. In this town, free food is a "must have" at any tech company of size now. I agree that's not normal in the rest of the world. But free coffee, drinks and snacks, parking are the norm, and free EV charging is quite common. Not only is it a recruiting perk, it makes the company seem a better global citizen.

In the future, when there is a solar surplus in the morning, charging at work will be the best place to do it.

Free coffee, drinks, snacks, and parking are all examples of tax-free fringe benefits that companies are explicitly allowed to offer their employees. They are deductible by the employer, not taxable to the employee, and not subject to payroll taxes. Companies save money on taxes by offering them.

Electric vehicle charging is not explicitly on the list of tax-free fringe benefits. If it’s not a tax-free fringe benefit, and you offer it to your employees, the value of it should be included on the employee’s W-2.

I’m not sure if IRS or Congress will find electric vehicle charging to be a tax-free fringe benefit, but they shouldn’t. Unlike the other categories, it is not “de minimis” and it is not a requirement of working on site. Taxpayers should not be subsidizing having people charge their vehicles at work as opposed to the home. The free market should decide which is better.

Well, when I worked at Google, they did not put the perks on the W-2. Not just mountains of food but many other things including free EV charging of course. I presume their tax lawyers know what they are doing.

However, should it come down to that, employers could simply offer free EV charging to the public. In reality only employees and visitors would use it. Particularly the 3kw charging I advocate, which is pretty much useless to anybody but employees and next-door neighbours. This would just be an expense, not a benefit, unless the IRS made a big effort to play with it.

However, once we start building out solar, with enough solar to power the grid from 3pm until sundown (peak usage) there will be a surplus of solar from 9am to 2pm, and the grid needs somewhere to put it. And so it's very likely the government will seek to encourage, not discourage, the installation of charging at work parking lots.

Of course, other things will encourage that. The power companies will be selling that surplus power cheap, so the cost of stations can easily be justified. And companies like to make happy employees. (One counter factor of course is there is pressure in some places to stop people from solo commuting. One might see free charging only for those who carpooled, who knows?)

I regularly charge at the supermarket for free. Nominally it is 50 kW DC (there is also 43 kW AC but the Tesla is limited to 11), and I usually get about 35. Ideal.

Why do you say that no-one ever charges to 100%? I‘ve done it a few times.

I should say that I am in Germany. 230V three-phase power is in every house. Usually normal plugs are 16 amps (some older ones just 10) and most houses have mostly one-phase plugs, but not all are on the same phase (which can make ethernet over the power lines a bit tricky). Home chargers are usually 11 kW (e phases at 16 amps and 230 volts), but even a normal plug will give 3.6 kw, which is often enough for overnight charging.

I bought my house from an electrical-hardware guy, and there is a three-phase connector in the cellar. Unfortunately the garage is not connected to the house and has no electricity, but that might change. At the moment, though, I don‘t need it.

Free charging at supermarkets is a bit of a prisoner‘s dilemma for the supermarkets: no matter what the competition does, they are better off offering it (the increased profit more than offsets the cost), but if all offer it, they generate less profit than if none offer it.

It is easier when the base voltage is up higher like that. I was not aware everybody had 3 phase, not ever having seen anything but the standard plugs. 3.6kw is definitely enough. With 3.6kw the typical driver might find they need to top up at a fast charger 1 or 2 times a year, making it non-economical to spend a lot to put in a 3-phase.

We talked about those free 50kw chargers -- those are rare here (I used some in British Columbia) and I would have to imagine over time they will go away, but I could be wrong on that. Germans pay about 30 cents/kwh, and if people are going in there for 40kwh fill-ups, that's 12 euros and is an expensive perk for a grocery store or restaurant to give. Particularly with the large cost of installing such chargers. Level 2 is much easier to give for free, but also not very useful.

However, yes, in the future, you should see grocery stores perhaps offering 50kw charging at cost. I predict though, that most drivers will be able to charge at home or the office -- leaving only those who park on the street and don't park at an office or commuter lot during the day as strongly in need of fast charging. That becomes less something you must have to get customers, but there will be a segment of customers who will choose their store based on that.

Essentially all buildings have three phases, but most plugs are just one phase (but not necessarily the same one). Some heavy-duty appliances tap into more than one phase.

I have also charged to 99% a few times on road trips when I knew I had the need. The reason "no one" (really meaning it is rarely done) does it is that it takes as much time to go from 90% to 100% as it does to go from 20% to 60% and cars will warn you to not do it very much, for good reason, though it's better if you are going to immediately drive after the charge so it doesn't stay at 100% for long.


I agree 350kW everywhere is overkill and government and state subsidies need to be to help apartment complexes and homeowners install at least 24 amp, 240 V stations. I believe 5.8 kW is the bare minimum, especially as battery packs get larger, and also a convenient way to make a 30 amp circuit servicing a clothes dryer serve double duty, as long as it is near where cars park. There are now companies that make "smart" switches that give priority to the dryer but at all other times let the car charge at 24 amps, and there is no risk of tripping the breaker. What are your thoughts about 10-11 kW at places where at least a 2 hour stay is probable (48 amps, either 208 V or 240 V)? More and more BEVs are coming standard with 11 kW on board chargers and I think this speed is extremely useful and fairly speedy for the cost - a 60 amp circuit is needed but not three phase power.

It is a common error to believe that 6kw is a bare minimum. I mean, faster is always nice, if it doesn't cost any more, but the average car drives under ~40 miles/day (15,000 per year) which is 10kwh and you can fill that in under 2 hours at 6kw, and almost every car parks 10 hours overnight.

People fixate on filling a car completely, which you almost never do, or even on the "optimal" fill-up of 20 to 80% which again, you almost never do in your home town. On road trips, sure, you do that a lot. Hotels should have 10kw at each station.

Even level 1 (12kwh in a night, or 18kwh at 20a) is enough for most cars almost all the time, especially if the pack is big enough.

You say we need more as packs get bigger. Actually we need less as packs get bigger, because you can tolerate more deviation from the average. What perhaps you meant is we need more as cars get less efficient, and that's more true. A pickup truck would like a bit more than a car, regardless of pack size, as it uses more kwh per day.

That's why I say that for an office or apartment building, you want mostly 3kw stations, because they are cheap. Put in mostly 3kw stations, and put in a few 7kw stations for those very few cars who need it. Discourage use of the 7kw stations by people who need less than 30kwh (120 miles) unless all the 3kw are full, to save them for the people who are down more than 40kwh.

You see, you only need a 40kwh fill up if you are both down that much and need to be able to go full range tomorrow. Except almost nobody is going full range tomorrow. The average person is going 30-40 miles tomorrow.

And anybody who is going full range tomorrow is almost by definition on a road trip and can use fast charging in that situation. And in the rare situations when there are too many cars that need 7kw stations, local fast charging will do the job.

Now, in hour house, putting in 7kw often costs only a little more than 3kw. So you might as well do it there in that case. If it doesn't, don't do it. But if you are putting 40 stations in a parking lot, no way you want to put in 40 7kw stations, that is going to cost a lot more in terms of your service level than putting in 5 7kw stations and 35 3kw stations. As a result, you might see people putting in just 20 7kw stations, which means half the people don't plug in or have to play games going out in the middle of the night to swap plugs.

Charging every other night does work, but you need a system to manage that. Simpler to just let almost everybody charge at their regular spot, or at one of the fast spots if they are very low.

Another option which works OK is to have paired 7KW stations with two plugs that will charge one car then the other. But you have to now plan, don't park two empty cars at the same paired station etc.

Only staying a short time, like 2 hours at a movie? Then you want as much as you can take. That's the paradox. The longer you will be at the charger, the less powerful it needs to be. Particularly if you will be there every day. The charger at your home is fine at 1.8kw (Level 1) for almost all days because you are there every night for 10 hours or more, often much more if you don't commute in that car.

The one problem not fully resolved is offices on Monday. There will be extra demand there from the people who have no other place to charge. To resolve this, offices might need to beef up a little more (Level 1 is not enough) or those people might use fast charging from time to time if they drive a lot on the weekend. Unless they have a large pack, in which case it's not a big problem, they can handle the extra burden of the weekend most weekends.

Do you really need to charge more on Monday? Sure, you're lower, but in general you only need enough to get you to Tuesday plus 1/5 of the excess to get you fully charged by Friday.

Many people will be fine picking up 120 miles on Monday. But a few more people will not be than on the other days. Anybody who drove a bit more on the weekend, in particular. It's a distribution. 40 miles is the average per day, but of course that's some people who went lower and some more. But you do need to handle them that day. However, a few 7kw chargers (with today's regime of swapping mid-day) may do the trick.

I would think that Friday would be the day when people need to charge the most.

On Monday, you only need enough charge to get you to Tuesday morning (at the most, assuming you can charge at work and are working five days a week). On Friday, you need enough charge to get you to Monday morning (assuming you don't have access to free or low-cost, convenient charging over the weekend).

It depends on how much you know about your weekend plans. Understand that with 3kw chargers at the office, which offer 100 extra miles in your stay at the office, almost everybody should be full by Friday evening, unless they drove a lot Wed-Thur. The office lot should have some fraction of the chargers by 7kw, and those to be used only by those who need more than 100 miles that Friday or any other day.

If you want to try to have the office be only 1.5kw Level 1, that's when you have more people leaving less than full who then are worried about their weekend.

But Monday you arrive down your full commute round trip plus all your weekend (or long weekend) driving. In theory, many of those only need enough to get back home and back to get the rest the next day, but people like the flexibility to change their minds and do an unplanned trip, so they like to stay above 50-60%.

Of course, one answer for the unplanned trip is the fast charger, and it is a good answer much of the time, though it comes with a small time and money penalty.

But I will stick with saying that Tuesday morning after a long weekend will be the time of peak demand by office chargers, and you must provision for near that peak. (Due to the fast chargers, you don't need to provision to fully meet it.)

I think you're bending over backwards to accommodate an irrational desire. If you want to do an unplanned trip, you pay a little bit extra.

With that said, if you (or your employer) would rather pay extra all the time, to avoid having to pay extra on rare occasion, that's fine with me.

Of course, all of this is moot because the real reason you generally want to go with faster chargers than you need is to be prepared for the future. You're probably not going to have 100% of workers using electric cars on day one. Faster chargers can be more easily shared between multiple workers. A single charger that is 10x as fast can handle 10 different cars in a 5-day work week. It could handle a few customers on the nights and weekends too, if it's in a convenient location.

The reason to bend over backwards is you want to say, "Your electric car is not inferior to a gasoline car when it comes to convenience of filling up, in fact it's superior." Charging at home is like that. It takes zero time since you sleep. You just drive. I am not a fan of inductive charging but there is something to be said about how seamless that would be in this department.

In a few years it is solved by cars that can drive themselves short distances and low speeds to charging stations where a human or robot (or the car, as a robot) plugs itself in.

That's the real answer. A "magic" car that's always full, you don't have to do a thing. It just needs to be able to guess when you don't need it for a while.

Anyway, we can do this for people in the city who can get charging at home or work. We can't do it for the rest, yet. And we have to accept that for now, gasoline is more convenient for road trips. But electricity is more convenient at home.

Seems like you want to say that, not me. I’m more realistic about it.

Electric cars can help us move to a carbon neutral world.. So far they seem to be the best alternative for doing that (though we shouldn’t forget that there are others). We’re going to have make some tradeoffs while moving to that world, but it’s something we have to do.

Yes, gasoline can be more convenient for road trips. So can biodiesel, for that matter, which can also be part of a carbon-neutral world.

There are two types of road trips. I think the fast chargers we have today are pretty good for the "Get where you are going on the interstate" sort of road trip. A little more time spent but usually easy to match with eating/etc. Pretty soon those chargers will be so frequent as to offer many choices. In addition, tons of people are working on sub-10 minute charging, which is not actually as useful as people imagine but is useful if you truly want to stop and not do much else besides pee and get a drink at the station.

That leaves the "back country" road trip. We still have a lot to make that quite as easy as it is with gasoline. And we could switch to biofuel there and have people who live there buy biofuel vehicles and reduce pollution.

I do think, though, that having city EVs (200 mile range) which can add a biofuel range extender when they want to do these road trips might be the best answer. That range extender could start on gasoline or diesel, and switch to the biofuel as the number of stations supplying that increases. That gives you a vehicle that can go anywhere gasoline vehicles used to go, which is what people want.

Yes, EVs aren't perfect, but to get wide public acceptance it would be nice if we didn't ask the public to step back.

There are lots of possibilities. I think they all lead to either 1) slightly higher costs for everyone, all the time, or 2) moderately higher costs for those people who choose to go on unplanned road trips, when they go on those road trips. I prefer 2.

But change “go on unplanned road trips” to something a little more common, and I can see how 1 would sell better.

all those electric cars are nothing else but huge waste of time and waste of money. "Luxury" Tesla 3 is a cheap, small and rubbish car full of useless and unnecessary "Hi"-tech crap with a price of $44000 and up. in my opinion, Tesla 3 is in the same class as Toyota Camry/Nissan Maxima/Honda Accord. I would prefer Camry anytime since it is more sturdy built--even the thickness of body metal is larger. yes, Tesla will save owners money because of an electric propulsion, but only when compairing to an expensive gasoline-powered car. otherwise, Tesla(and other electrics) will be at a loss because of a high price tag. ok, how about all that charging nonsence and headache with electric cars? even with "fast" charging it is way too slow. i just don't want to spend 30 minutes "fast" charging Tesla while it takes only 3 minutes to fill up a gas tank in a regular car. Ha-ha-ha... charging overnight at home or motel. yeah, tell that to younger people. what, Tesla owners must be on nationwide curfew, or something, because they can't drive it while it is recharging overnight? no Carbon emissions from electric cars-that is correct. but electric power stations will pollute more since more and more Watts will be required to recharge cars. electricity prices may go up as well because of demand. well, the technology will advance, and when recharging an electric car will take only like 3 minutes or so, than it will be something that people want, if they could afford it. now electric cars are just some new moneymakers for auto companies and expensive toys for rich owners that are not really fun to play with.

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