Model X has single 72A charger

[Larry Chanin]

seems to me that the HPWC is in a little bit of a dead place in the range of products. It's most useful for places you're going to stop for an hour or two--restaurant, rest area, shopping mall, etc. But you can't really take advantage of it unless you're carrying around dual chargers. So most of them are in people's garages, where single charger rates are all that's needed. Without dual chargers, there's little advantage over a level 2 J1772.

What if they're replacing the HPWC with a sort of mini-supercharger: a stack of two or three of the rectifier/chargers from a supercharger and the cord like the one in the HPWC, in a suitable case. It would a lot less site preparation and electrical rigmarole to set it up, which would make it a lot easier for "destinations" to install them than full superchargers, and nobody has to carry around dual chargers to use it. Any supercharger-enabled car can use it. It would expedite the filling-in of the supercharger map: as it stands, there are a lot of places that are only 20kwh or so out of reach--an hour at a mini-supercharger, but two or three at a J1772 or 14-50.

I notice that dual chargers is no longer an option on Tesla Motors | Premium Electric Vehicles. am missing something or is this a consequential change?

--Snortybartfast

It's less expensive than similar capacity J1772 EVSEs, and about the same price as 40A J1772 EVSEs. It's generally smaller than similar J1772 EVSEs, you don't need an adapter, and you can open the charging door with the button on the handle. It doesn't have to be installed on a 100A circuit for it to be worthwhile. If you intend to plug in only Teslas, why pay more for a J1772 EVSE?




The dual chargers haven't been a factory option for a long time. They are installed by service centres now.

Tesla Accessories and Charging Adapters Dual Charger with Installation

The "rectifiers/chargers from a Supercharger" are exactly the same units as are installed in the car, working in parallel. (Which is brilliant engineering, if you ask me.) So I don't understand at all what you're proposing. You're suggesting duplicating the expense of the chargers in the car by putting the same chargers in a box outside the car? Why? The limit is the circuit connecting to that box. It's tough enough finding a 100A 240V circuit in a home, where are you going to find these higher power circuits? Unless you can go to a higher voltage, you are talking about seriously thick wiring to connect to this new mini-Supercharger box.

By contrast an HPWC is essentially an intelligent relay switch. Much, much cheaper.


Love your name, btw. Was it a long trip from Magrathea?

Yes, I know the difference between an EVSE (such as the HPWC) and a charger. Tesla's got a more elegant design, but they aren't trying to make a profit on them like Clipper Creek and Aerovironment and so forth are. They want to use them as a motivation to sell more cars. They want to get as many places to charge as possible. Cheap and simple is one way to do that, but it's not working too well.

there are about 100,000 model Ss and less than 3000 supercharger berths. for home charging, the second charger isn't good for much...it's really only valuable on long trips...the same purpose the superchargers are serving. so a lot of people have made the sensible choice to not install one. consequently, destination HPWCs aren't that valuable at destinations...a hotel or restaurant or whatever might as well install a J1772 and use it to bring in more customers.

BUT, superchargers are expensive and time consuming to install. A bollard with two car-type chargers inside and a big enough cord, which implements a 20kw version of the supercharger protocol, would cost less than $10K to install /including/ the hardware and paying the contractor and electrician. no special permits or inspections needed and any electrician/inspector capable of installing the present HPWC can do it. any car that accepts supercharging can use it. a lot more useful than an HPWC and only a little more expensive. 10-15 of them can be installed for the price of a single supercharger and they're almost as useful. They'd be part of the same supercharger program: the restaurant or mall or whatever wouldn't pay for anything but the parking space; Tesla would pay. Scatter them all over, in places that are unlikely to get superchargers for years to come. More incentive to buy a Tesla.



It was, but I'm not allowed to talk about that.

Coincidentally, this is my 42nd post on this forum :biggrin:

-Snortybartfast.

I find a mini-Supercharger an intriguing idea, and yes it is cheaper than a full-sized Supercharger. However, I am not following the economic advantages of scaling DC fast charging down to around 20 kW when compared to 20 kW AC charging on an HPWC.

You may have seen that BMW is subsidizing a 24 kW CHAdeMO DC fast charger. It's subsidized price is over $6,500 (I don't believe that includes installation costs). It weighs 125 pounds and it requires a 480/277 volt, 3-phase power source from the utility. In comparison an HPWC's retail cost is $750. It weighs 20 pounds and it only requires a 240/208 volt, single phase power source from the utility.

How is a Tesla mini-Supercharger of around 20 kW any better than the dubious BMW "fast" charger concept?

Larry

- - - Updated - - -

On another subject, currently Tesla's Supercharger network is built around a stack of the same chargers that it install in its cars, currently 10 or 11 kW each. I imagine that if Tesla decided to introduce 15 kW chargers in its cars that for economic reasons it might likewise begin to adopt them as the standard for new Superchargers. A stack of 8 would accommodate a 120 kW Supercharger. As batteries get larger the charging rate of cars would likely increase. So Tesla could stack say ten 15 kW chargers for future cars that might be able to handle 150 kW. Even though the capacity of a stack of ten 15 kW chargers would exceed the charging capacity of existing Model Ss, it still would provide advantages by increasing the throughput of a Supercharger Station by providing a higher average charging rate during the course of a day. The car's firmware would of course limit the maximum charge rate that it can handle, but having additional capacity at Supercharger Stations would be very helpful at congested or fully occupied stations. In other words, 75 kW of capacity could be delivered to both cars connected to the same Supercharger instead of just 60 kW. (I know that currently Tesla Supercharger firmware doesn't divide the capacity in half, but rather the capacity is shared in 30 kW increments, so it would be 90 kW to 30 kW between cars. If Tesla choose to use 150 kW Superchargers it could be 100 kW to 50 kW between cars. The point is that more capacity would be available to be shared in whatever manner Tesla chose.)

Larry

 

[PoweredByRain]

HPWC: A wall connector that includes Tesla charging cable and handle. Can be directly wired to 100A/240V circuit, which would provide 80A or 20kW of charging.

Power = Current * Voltage. 80A at 240V is 19.2 kW, not 20 kW. More to the point, the voltage will sag under load to usually about 230V, so what you'll actually see is 18.4 kW. Unless you're on a 208V circuit, which generally sags to under 200V under load, in which case you'll see 16 kW.

80A != 20 kW. Commercial installations are generally on 208V circuits so for public chargers 80A generally means 16 kW.

I wish people would not confuse these things. The charger is limited by current, not by power. The 20 kW figure is due to the rating of "up to 250V" at 40A.

NEMA 14-50: A standard wall outlet that runs at 50A/240V. This delivers 40A or 10kW, around 29mph.

Again, 40A is not the same as 10 kW... unless your circuit is at 250V, which it isn't.

The reason why you get 40A continuous from a 50A circuit is because continuous loads are limited to 80% of the circuit breaker rating. There is some confusion as a result, since some manufacturers refer to the maximum input circuit current rather than the maximum output circuit current. The latter is what we really care about. So for example a Clipper Creek HCS-30 provides 24A, not 30A. (24 is 80% of 30).

And back to the Model X: If there is a new charger in the Model X capable of 60A, I'll bet you it's the same sort of "master-slave" arrangement and you'll be able to get a second 60A charger. People seem very confused about the second charger in a Model S ever since Tesla deleted it as a factory option. It didn't go away, it just became an "install after delivery" product. ($2000 at your nearest service centre).

 

[snort]

I find a mini-Supercharger an intriguing idea, and yes it is cheaper than a full-sized Supercharger. However, I am not following the economic advantages of scaling DC fast charging down to around 20 kW when compared to 20 kW AC charging on an HPWC.

You may have seen that BMW is subsidizing a 24 kW CHAdeMO DC fast charger. It's subsidized price is over $6,500 (I don't believe that includes installation costs). It weighs 120 pounds and I assume it requires a 480/277 volt, 3-phase power source from the utility. In comparison an HPWC's retail cost is $750. It weighs 20 pounds and it only requires a 240/208 volt, single phase power source from the utility.

How is a Tesla mini-Supercharger of around 20 kW any better than the dubious BMW "fast" charger concept?

Larry

In order to charge at 20kw with the present HPWC, you need to have dual chargers. not many people are buying them, so they are limited to charging at 10kw. a little better than typical J1772 but not much. That's not a compelling reason to install a HPWC at your restaurant, mall or rest stop, and consequently, Tesla doesn't get the promotional value of people becoming familiar with them, and comfortable that they'll find them most everywhere, like gas stations. when you plan a trip in an ICE, unless it's seriously into the wilderness, you don't even think about where to gas up until it's time to do it...Tesla is trying to achieve something like that.

Superchargers are expensive, take some specialized skills to install and inspect, and require some serious wiring from their local substation, all of which takes time. The HPWC takes a few hours to install and doesn't require any specialized wiring or skills. the electrician that did mine hadn't done one before, but skimming the installation pamphlet was more than sufficient. The mini-supercharger I propose would be just as easy and take exactly the same input power, although it'd be a little bigger. The on-board version of the charger costs $2K installed and the HPWC costs $750...hard to imagine it costing tesla more than about $3K to make a 2 charger miniSC. They could sell them for private owners for $5K and pay local electricians to install them at locations they think worthy...back roads, tentative supercharger locations, rest areas, etc. Even put them on tow trucks. And there's no reason there couldn't be 3 or 4 charger versions.

the CHAdeMO adapter is a little like dual chargers, in that most people don't have them and that doesn't get Tesla the "charge anywhere" advertising they need. most CHAdeMOen are relatively close to big cities, where small battery EV drivers can use them, but basically none on cross country routes the way Tesla's placed the superchargers. So much for letting the free market decide. Tesla needed to take matters into their own hands with the supercharger network. Eventually, the free market will catch up, but Tesla understands that building market share and more importantly, mind share, is far more valuable. Getting people to understand that they really can charge their Tesla just about anywhere will sell far more cars than great reviews in consumer reports. The buildout is happening amazingly fast, but even that may not be fast enough. I think they need at least 1000 Tesla super charger locations in the US on the day the Model III ships. (there are 168,000 gas stations in the US)

 

[PoweredByRain]

It's an interesting idea, snort, but first of all I don't think you've considered how much time and effort (and thus cost) is involved in certifying something like what you're proposing. I don't think Tesla would invest in that unless there was a big payoff, and I just don't agree that there is a big payoff. And second: $5000 versus $750? For the same power?

Why wouldn't third parties want to just install the $750 unit? If it's a hotel then it matters exactly not a whit if the Model S owner using it happens to not have dual chargers; it'll still charge the car overnight. As for other sites - if people really cared, they would get the dual chargers. The Supercharger network will be dense enough that I really don't see the utility of what you're proposing.

 

[andrewket]

Slightly off topic, but if Tesla is doing anything with chargers, I'd like them to come up with a two-headed HPWC for two Tesla households that works like the Superchargers where it is smart enough to split the charging between the two plugs.

I have a dedicated TOU meter with 100A circuit that feeds my HPWC. When our MX shows up, I am not quite sure how I am going to handle charging both vehicles:
1) Single HPWC running @80A and manually move it between vehicles (PIA)
2) Add a second HPWC and run both at 40A - problematic as there are days (nights) when I need a quick turnaround

I guess I could run both HPWCs at 80A (or 80A/60A) and use the timer to make sure they are not charging at the same time, but it opens up an chance I'll kick the breaker both vehicles try and charge at the same time for some reason.

Tesla has a patent on a dual head EVSE that load balances. I'm in the same boat as you, but with 3 EVs: S, X, and a Volt.

 

[snort]

It's an interesting idea, snort, but first of all I don't think you've considered how much time and effort (and thus cost) is involved in certifying something like what you're proposing. I don't think Tesla would invest in that unless there was a big payoff, and I just don't agree that there is a big payoff.

Less than the cost of a single supercharger. Probably much less, because all the components are already certified. The only new thing would be the software and the same team that did the supercharger and CHAdeMO adapter could probably cook that up in a few days. Since they'd be making thousands of them, negligible.

Why wouldn't third parties want to just install the $750 unit? If it's a hotel then it matters exactly not a whit if the Model S owner using it happens to not have dual chargers; it'll still charge the car overnight. As for other sites - if people really cared, they would get the dual chargers. The Supercharger network will be dense enough that I really don't see the utility of what you're proposing.

Exactly. For a hotel, it doesn't matter. Might as well go with a J1772 and get Leafs and Volts and i3s. For a restaurant, rest area, shopping mall, etc., where folks spend an hour or two, it matters a lot. Hotels are often co-located at such places, but don't let it confuse you. It's simply that they've got more parking spaces to spare than the coffee shop or fast food place next door. For Tesla, the priority is to get folks to believe they can charge most anywhere. I'd think they'd be happy to subsidize such places in present supercharger deserts.


--Snortybartfast

 

[Larry Chanin]

Why wouldn't third parties want to just install the $750 unit? If it's a hotel then it matters exactly not a whit if the Model S owner using it happens to not have dual chargers; it'll still charge the car overnight. As for other sites - if people really cared, they would get the dual chargers. The Supercharger network will be dense enough that I really don't see the utility of what you're proposing.

Exactly. For a hotel, it doesn't matter. Might as well go with a J1772 and get Leafs and Volts and i3s. For a restaurant, rest area, shopping mall, etc., where folks spend an hour or two, it matters a lot. Hotels are often co-located at such places, but don't let it confuse you. It's simply that they've got more parking spaces to spare than the coffee shop or fast food place next door. For Tesla, the priority is to get folks to believe they can charge most anywhere. I'd think they'd be happy to subsidize such places in present supercharger deserts.

--Snortybartfast

For locals driving a Tesla with 200+ miles range, eating at a local restaurant, or shopping at a local mall it simply doesn't matter. They don't need the charge at any speed. It's just a "nice to have" amenity, not a necessity. However, as you point out it certainly does matter to the host location whether they are paying $750 for charging equipment or several thousands if in both cases they are still only getting 20 kW for a Tesla proprietary charging solution. (We have 16 chargers at our local mall with great restaurants. Four of them are HPWCs. Only on rare instances do I actually connect to them while at the mall.)

In my view only a mini-Supercharger solution of several times more than 20 kW makes sense and that would be for road trip situations where a full Supercharger is not available or feasible. Having another relatively low cost Tesla DC charging option (with capacity greater than an HPWC, but less than a full Supercharger) could open up self-sustaining business models by third parties if Tesla permitted it. I could definitely see this being very useful when Tesla is building several hundreds of thousands of affordable Teslas a year.

However, a stack of more than two chargers at 240/208 volt input voltages as you suggested earlier quickly becomes impractical due to current carrying considerations. I think that the mini-Supercharger concept would have to remain geared for 480/277 volt inputs.

Larry

 

[JanoSicek]

For Europe there are only these options:

a) < 11 kW (small sockets, at least 4 standards)
b) exactly 11 kW (three phase 16A)
c) exactly 22 kW (three phase 32A)
d) exactly 44 kW (three phase 64A)

Because of this standardization, it does not make sense to offer anything else than 11 or 22 kW chargers. Model S has 11 kW per charger.

 

[scaesare]

For what it's worth, that post has been disproven many times and was just rampant speculation by a guy who tends to be anti-Tesla most of the time.

Tesla has said that you don't need to worry about supercharging, and in technical forums they have said it could be supercharged every day without significant impact to the battery.

This.

And what's more, the idea put forth earlier that "...60 amps charging would definitely preserve battery lifetime over 80+ amp charging." is very unlikely to make any discernible difference in the context of the size of the onboard chargers being discussed here.

A 240V/80A=19.2kW charger delivers a charge rate of 0.23C.

Dropping that rate down to 60A delivers a charge rate of 0.17C.

That's a meaningless difference of 0.06C to a generic battery family chemistry that safely can charge at 1C, and with the specific implementation in the Tesla that charges at 1.59C at 135kW superchargers.

Tesla is not doing this (if they indeed are) for any battery protection reasons.

 

[Red Sage]

Mark Z: Great information (even if it was about charging)!

Sometimes I wish this bulletin board wouldn't stop me from adding well deserved kudos...

 

[ohmman]

Power = Current * Voltage. 80A at 240V is 19.2 kW, not 20 kW.
...
I wish people would not confuse these things. The charger is limited by current, not by power.

I'm aware. Read upthread for more discussion on the amperage vs. power discussion. Additionally, there are plenty of resources on this site that make this very clear. My answer was for O-G (and, to some degree, lucy) who had asked for a simple summary.

With regards to the MS dual charger option, it's been noted that it became "install after delivery" because uptake was slow. I don't think it's meaningless that they have removed it from the order page.

 

[Yggdrasill]

For Europe there are only these options:

a) < 11 kW (small sockets, at least 4 standards)
b) exactly 11 kW (three phase 16A)
c) exactly 22 kW (three phase 32A)
d) exactly 44 kW (three phase 64A)

Because of this standardization, it does not make sense to offer anything else than 11 or 22 kW chargers. Model S has 11 kW per charger.

I disagree. There's nothing wrong with only charging at 15 kW at a 22 kW charging point. When you connect to a Type 2 charging point, the charging point will inform the car how much is available, and then the car will start charging at the highest rate permissible by both the car and charging point. It's just like charging a Model S at a 43 kW AC charging point. Even if you "only" get 22 kW, that's still not too bad.

 

[FlasherZ]

You may have seen that BMW is subsidizing a 24 kW CHAdeMO DC fast charger. It's subsidized price is over $6,500 (I don't believe that includes installation costs). It weighs 120 pounds and I assume it requires a 480/277 volt, 3-phase power source from the utility. In comparison an HPWC's retail cost is $750. It weighs 20 pounds and it only requires a 240/208 volt, single phase power source from the utility.

I suspect that if you scale down a DC fast charger, you could easily put it on a single-phase service. 24 kW is one of those magical numbers (125A on continuous breakers, a standard trade size).

Ultimately, though, as long as Tesla believes there's a need for mobile charging other than superchargers (and I believe there is), there isn't any economic reason to put a charger in the car and sell a charger stack to a homeowner. Taxi companies and such can work with the higher end stuff, but small DC fast chargers just aren't going to be realistic.

- - - Updated - - -

Again, 40A is not the same as 10 kW... unless your circuit is at 250V, which it isn't.

The reason why you get 40A continuous from a 50A circuit is because continuous loads are limited to 80% of the circuit breaker rating. There is some confusion as a result, since some manufacturers refer to the maximum input circuit current rather than the maximum output circuit current. The latter is what we really care about. So for example a Clipper Creek HCS-30 provides 24A, not 30A. (24 is 80% of 30).

My home runs at 248V, so I come very close to it.

There's a technicality with your description of the continuous load rule. It states that the circuit rating must be 125% of the offered continuous load; it doesn't limit the load to the breaker, but rather it creates a minimum floor for circuit rating. This makes a difference when you begin to look at other de-rating factors. You are correct in the absence of any other factors that you would be limited to 80% of the breaker size (because that's what 1 / (125%) is, but that's not specifically what the rule says.

- - - Updated - - -

Superchargers are expensive, take some specialized skills to install and inspect, and require some serious wiring from their local substation, all of which takes time. The HPWC takes a few hours to install and doesn't require any specialized wiring or skills. the electrician that did mine hadn't done one before, but skimming the installation pamphlet was more than sufficient. The mini-supercharger I propose would be just as easy and take exactly the same input power, although it'd be a little bigger.

I think there's probably going to be an aesthetics issue to a stack of chargers, even a small stack to gain you 24 kW. You're going to take wall space (or floor space), and cooling is a necessity. The beauty of integrated chargers in the car is that it can be tied into the cooling / fan systems the car already needs. I can't see a mini-supercharger getting to anything less than 3x the size of the existing HPWC *at best*.

 

[ecarfan]

[rumor] MX Single 60A charger

And second: $5000 versus $750? For the same power? Why wouldn't third parties want to just install the $750 unit?

And let's not forget that, in the USA at least, Tesla is giving away HPWCs to destinations. The only cost to destinations is wiring it up, and I know of at least one instance I was personally involved in where Tesla offered to contribute towards the cost of installation, and also offered the destination a Clipper Creek J1772 unit!
So destination HPWCs are free. Any sort of DC charging unit costs thousands.

 

[Larry Chanin]

I suspect that if you scale down a DC fast charger, you could easily put it on a single-phase service. 24 kW is one of those magical numbers (125A on continuous breakers, a standard trade size).

Ultimately, though, as long as Tesla believes there's a need for mobile charging other than superchargers (and I believe there is), there isn't any economic reason to put a charger in the car and sell a charger stack to a homeowner. Taxi companies and such can work with the higher end stuff, but small DC fast chargers just aren't going to be realistic.


I think there's probably going to be an aesthetics issue to a stack of chargers, even a small stack to gain you 24 kW. You're going to take wall space (or floor space), and cooling is a necessity. The beauty of integrated chargers in the car is that it can be tied into the cooling / fan systems the car already needs. I can't see a mini-supercharger getting to anything less than 3x the size of the existing HPWC *at best*.

Yes, at 24 kW it would be feasible to put it on a single-phase service, although the BMW 24 kW CHAdeMO specifies a 3-phase 400-480 volt service.

I agree that it doesn't make sense for a mini-Supercharger to be anything less than about 3x the size of an HPWC. However, at that capacity for current carrying reasons it becomes more feasible to go to a 480 volt service. I suppose a utility could stock a single phase 480 volt supply transformer, but at that voltage they usually stock 3-phase units. If a mini-Supercharger Station were to have more than one charger three phases would come in handy for additional units.

Larry

 

[snort]

I suspect that if you scale down a DC fast charger, you could easily put it on a single-phase service. 24 kW is one of those magical numbers (125A on continuous breakers, a standard trade size).

Ultimately, though, as long as Tesla believes there's a need for mobile charging other than superchargers (and I believe there is), there isn't any economic reason to put a charger in the car and sell a charger stack to a homeowner. Taxi companies and such can work with the higher end stuff, but small DC fast chargers just aren't going to be realistic.

...snip...

I think there's probably going to be an aesthetics issue to a stack of chargers, even a small stack to gain you 24 kW. You're going to take wall space (or floor space), and cooling is a necessity. The beauty of integrated chargers in the car is that it can be tied into the cooling / fan systems the car already needs. I can't see a mini-supercharger getting to anything less than 3x the size of the existing HPWC *at best*.

I think that's the right analysis. There will small commercial users who can justify having their own DC fast charger. taxis, package delivery, etc. A 30kw stack would be able to charge at 90mph...enough to charge up for the whole afternoon during lunch break. A taxi company with 50 cars might have several of these...a lot cheaper than dual chargers in every car.

I think the installation at malls and restaurants will be more like a bollard than a wall charger. It'll be outdoors. folks who will have them at home will be the type for whom price is no objection.. They'll find a place to put it, even if it means hanging it from the ceiling to get it out of the way. I don't know if there are enough of them to justify a wall mount (aesthetically, like a powerwall) version.

your point about sharing cooling with the car is valid. It won't be too hard to add that to the bollard though.

--Snortybartfast

 

[SW2Fiddler]

[rumor] MX Single 60A charger

I think the installation at malls and restaurants will be more like a bollard than a wall charger. It'll be outdoors.

"Press Here to view two short ADs to release the Charge Cable and start your COMPLIMENTARY charging session!"
Cue video of mouth-watering food images to lure you inside...
Charging at twelve-teen kilowatts ensues...

(witness the sponsored phone-charging kiosks inside the malls ALREADY)

Maybe it collects your ZIP Code. Teslas coming from 90210 could get targeted different ads from LEAFs from 77-ought-nada...

 

[hiroshiy]

We are getting off topic here, but I'd like to share what happened to Japan. We now have only six superchargers here, the last one added last March and nothing since then.

We have 6000 CHAdeMO chargers that Tesla can use. Out of those, many of them are 20kW. The reason was exactly what FlasherZ described: 20kW was the upper limit of single phase service here at 200V AC. There are only a few manufacturers that offer single phase CHAdeMO chargers and they are more expensive side, for example this Nichikon costs $18K.
ƒjƒ`ƒRƒ“Š”Ž®‰ïŽÐ | »•i‚Ì“Á’· | “d‹CŽ©“®ŽÔ—p‹}‘¬[“dŠí
# It's a very complex site so it says 30kW never mind.

Our electrical service is as follows:
200V single phase up to 49kW: same cost as home power
200V three phase up to 49kW: more expensive, high per-kW (not kWh) monthly charges
6600V three phase: very cheap per kWh rate with high per-kW annual demand charges, you own your transformer, one transformer per one location
In metro areas you get 22000V feed

So just going up to three phase it will push the electricity cost higher up.

They are much cheaper compared to Superchargers or high power CHAdeMOs that require high voltage feed, but still, because its size and weight, it requires some concrete pouring, cooling system, and regular maintenance that would add the cost up. Now the charger is separate from the building, you need some bollards to protect the charger, and need underground trench to bury the cables.

IMHO HPWC is very cheap and very suitable for destination charging. For needs like in-between Superchargers, there is already Combo or CHAdeMO and Tesla doesn't have to reinvent the wheel.

 

[snort]

We are getting off topic here, but I'd like to share what happened to Japan. We now have only six superchargers here, the last one added last March and nothing since then.

We have 6000 CHAdeMO chargers that Tesla can use. Out of those, many of them are 20kW. The reason was exactly what FlasherZ described: 20kW was the upper limit of single phase service here at 200V AC. There are only a few manufacturers that offer single phase CHAdeMO chargers and they are more expensive side, for example this Nichikon costs $18K.
...snip...

They are much cheaper compared to Superchargers or high power CHAdeMOs that require high voltage feed, but still, because its size and weight, it requires some concrete pouring, cooling system, and regular maintenance that would add the cost up. Now the charger is separate from the building, you need some bollards to protect the charger, and need underground trench to bury the cables.

IMHO HPWC is very cheap and very suitable for destination charging. For needs like in-between Superchargers, there is already Combo or CHAdeMO and Tesla doesn't have to reinvent the wheel.

I looked at the plugshare map of Japan and there are no CHAdeMO deserts anywhere. the biggest is about 100km and there don't seem to be many roads there either. In Japan, a Tesla driver would be nuts to not carry a CHAdeMO adapter on a cross country trip.

This is what I want (and I think Tesla wants) for the US. whether, exactly, it's CHAdeMO or something else is less important than that the big deserts get filled in. There are a few routes where CHAdeMO will help in the US, but for most of the west, they are mostly clustered around big cities. superchargers are already more useful.

I think a 20kw mini-supercharger to run on US power could be built for $4K each. add installation cost and profits and private ones would cost about $10K installed. Tesla is likely to subsidize ones in existing charger deserts, just as they do now for HPWCs and superchargers, because it adds to the value of the car. (I think a 48kw mini would cost $10-15K to build, uninstalled, so factoring in profits, that's consistent with CHAdeMO costs.)

should we make a new thread? I started this digression, but I'm new here. How do we do this?

 

[PoweredByRain]

Less than the cost of a single supercharger. Probably much less, because all the components are already certified. The only new thing would be the software and the same team that did the supercharger and CHAdeMO adapter could probably cook that up in a few days. Since they'd be making thousands of them, negligible.

The cost of UL certification is negligible? Really?

As was pointed out, there would have to be a cooling system, whether installed indoors or outdoors. (Listen to the fans going when charging outdoors in 40 degree (104 F) weather...)

I think you're waving away some rather significant costs.