Future Charging for Model S 1-phase or 3-phase ?

[VolkerP]

@Norbert,

If I count it this way, the 3 phase is a no-brainer:

HPC = imbalanced load, €2000 materials cost, max 16kW. Approx. number in Germany, Switzerland, or UK: dozens.

32A CEE = (possibly) balanced load, €40 materials cost, max 22kW. Approx number in the thousands in most European countries.

 

[widodh]

HPC chargers at hotels and otherwise available for travelling, in Germany and UK are 60A - 70A, see this thread:
Supercharger plans for Germany

Especially this page:
Supercharger plans for Germany

That's more than enough for <10 hours charging for even the 300 mile pack. Not sure though in how many places this will be available, though. The map shows a few for the german area, but surely more than those are possible. Maybe a rather common possibility for hotels?

Like dpeilow said, finding 60A free on a circuit board is not that easy. And you'll inbalance the phases, so it's a pita to get a HPC installed.

Looking back at your previous messages, is this then mainly 12 times a year? (+ additional journeys, of course)

Those are my trips to France or Germany.

I go to Amsterdam quite often, it's a ~200 km trip. Our highway speeds are 130km/h (80 mph), so I won't make the round-trip on a single charge.

I'll have to charge at my destination, 11kW or 22kW charging would be enough to let me make the round-trip in all comfort (HVAC & radio) I want. I don't want to arrive home with a nearly depleted battery, I wan't to have a bit spare.

Here again, a 400km round-trip which can be done without DC charging where just AC medium power would work.

It is plain simple, in Europe 10 ~ 20kW AC charging can only be done with 3-phase power and those outlets are widely available (Tens/Hundred of thousands) throughout Europe.

 

[Norbert]

The UK grid is different and it is easier to install a high single phase load without paperwork. It is still a major PITA to find that much free on a hotel fuseboard. Electricians still suck air through their teeth and talk about imbalance.

In Germany it requires lots of exemptions from utilities etc. In Italy we have seen they had to install three HPCs to be allowed to do it.

On the other hand no one thinks twice about installing a 32A three phase outlet in these places. It is easier from a practical and no paperwork point of view.

So what happens when you want 2, 3 or 10 of them?

 

[eledille]

Norbert, I really can't understand why you keep doubting the need for 3-phase. It's the cornerstone of the European EV effort. What Tesla, Nissan or anybody else thinks doesn't matter, European engineers and politicians are not going to listen to foreigners telling them how to use their power grid. An EV in Europe that does not support 3-phase will be as out of place as a penguin in the Sahara desert.

Please read this, I have devoted more than an hour to explain this as carefully as I can. If there's something in here that you don't understand, you're welcome to send me a PM.

In Europe, power is distributed in the form of 3-phase AC at 400 V. Phase-to-phase voltage is 400, phase-to-neutral voltage is consequently 230. You get single phase by wiring between one of the phases and neutral. Each phase necessarily has its own main fuse. The available single phase power is thus split between three equal-sized main fuses, each of 1/3 the rating it would have had if there was a single phase supply instead. A high amperage circuit is therefore three times harder to get hold of than in a single phase distribution system.

16 A, 400 V, 3~ equals 46 A, 240 V.
32 A, 400 V, 3~ equals 92 A, 240 V.
63 A, 400 V, 3~ equals 182 A, 240 V.

Keeping the amps down is a major virtue of the three phase system, losses and wire size are proportional to current. Higher voltage also proportionally reduces current for the same power. That's why a 20 meter 16 A 3-phase extension cable costs about a hundred dollars and can be stowed under a seat. The voltage drop at full load is 4.8 V, which is perfectly acceptable.

A 70 A single phase connection for an HPC requires an 80 A service drop, this is the closest higher standard fuse size. If this service drop is not dedicated to the HPC charger, you would have to double that size to be reasonably certain of finding sufficient free space.

Thus we in practice end up with needing at least a 160 A, 400 V service. This equals a 460 A 240 V service. Now, which are easier to find, 100 and 200 A service drops, or 500 A?

Does your house have a 500 A service drop?

How would you feel if you were to try to talk your boss into paying for something like this to be able to charge efficiently at work? What if the electrician went to your boss and said "Are you really sure you want to do this? It's doable, but really awkward, and I'll have to talk to the utility first. Can't you just use an ordinary 3-phase connection"?

Would you feel more confident asking for a stock standard 11 or 22 kW outlet that costs less than a thousand dollars?

What happens when a collegue wants to charge his new Renault and discovers that you are hogging all the free three phase capacity and only actually use one third of it?

You have to understand that 3-phase is the norm here. Single phase is never used above 16 A except for electric stoves. Even these are usually 3-phase. Single phase above 25 A is never used, except when people are going out of their way to help the owner of a very strange and foreign all-carbon sports car.

Norway is a little different from the rest of Europe, since we also have 230 V 3-phase, but 230 and 400 V 3-phase systems have the same pros and cons compared to single phase.

If you use the 3-phase power directly, you have no problems. The load will be distributed equally between the main fuses, and you get in total three times more power per ampere.

Some sites will have a huge amount of power available. Then you can get a 32 A or maybe even a 63 A single phase connection. But that would always be done by connecting only one of the three phases. There will always be three times more power available than you can actually use in this way. Do you really think that is an adequate solution?

3-phase is much, much better suited to charging EVs than single phase. I won't rehash all the reasons now, but the net result is that you get twice the power for the same weight and cost.

In addition to all of the above, the whole 3-phase charger has already been integrated into the PEM by a major manufacturer, allowing reuse of the regeneration circuitry and its cooling system for charging from the 3-phase grid.

It's quite simply completely idiotic not to take advantage of 3-phase power where it is available.

Not supporting it at all in Europe, a market which without 3-phase would be limited to 3.7 kW, and whose own auto industry is supporting it, is suicidal.

 

[widodh]

You have to understand that 3-phase is the norm here. Single phase is never used above 16 A except for electric stoves. Even these are usually 3-phase. Single phase above 25 A is never used, except when people are going out of their way to help the owner of a very strange and foreign all-carbon sports car.

True. I just got my new house (busy with decorating) and I've got electrical cooking. This draws 2x16A split over two phases. Yes, this could have been 1x32A, but it draws its power from 2x16A. I could also have taken a bigger one, would have drawn 3x16A


A few pictures of the circuit board of my house (work in progress!) to show you how this works:

- One picture shows you my three main fuses of 40A coming into my house with the kWh counter after it
- Another shows you the circuit board closed
- And the other shows you the circuit board opened up

The cable coming into my house is dimensioned for 3x40A maximum, that is all I can get.

3x40A should be sufficient for all the power I need and charging a Model S with 3x16A when I'm cooking and with 3x32A when my power usage is low.

 

[EV_de]

... I Still don't understand this discussion ....

with 3 phase charging i do not need any charging station AC/DC "midPower" , "HighPower" , "Superpower" or what ever !

I do not want to change my dependence from oil companys to a dependence of a charging station company ....

With 3 phase I can charge allmost everywhere in germany , at Home , Office , our Customers , Farms , Campgrounds a.s.o. .... without a (hugh) external charging device ...

 

[Norbert]

... I Still don't understand this discussion ....

with 3 phase charging i do not need any charging station AC/DC "midPower" , "HighPower" , "Superpower" or what ever !

Another voice saying 3-phase (more or less) replaces the need for DC fast-charging. This is what I disagree with.

However I do not have a fixed opinion about whether 3-phase is needed or not, although I have some interest to find out, and ask questions about it.

There aren't any signs that Tesla already agrees with you, so if I were in your position, I'd hope that a discussion would help your case. From my point of view, that is what you need to understand my part of the discussion.

 

[doug]

Once again this not the "let's repeatedly explain how some things are different outside the US to Norbert" forum. If you don't understand by now why Europeans want/need 3-phase, then you probably won't. If you disagree, then fine and leave it at that. Forcing a circular discussion is tantamount to trolling and is getting tiresome.

 

[widodh]

Another voice saying 3-phase (more or less) replaces the need for DC fast-charging. This is what I disagree with.

However I do not have a fixed opinion about whether 3-phase is needed or not, although I have some interest to find out, and ask questions about it.

There aren't any signs that Tesla already agrees with you, so if I were in your position, I'd hope that a discussion would help your case. From my point of view, that is what you need to understand my part of the discussion.

You can interpret this multiple ways.

Imho he is just saying that 20kW AC power would be sufficient for his driving. It is even more power then the current HPC deliver (thus more KM's per hour of charge).

I'm not saying that I don't want DC charging, but I think I'll rarely use it when I'm able to charge at 10kW or 20kW since this is so widely available.

One thing I thought of, a true 3-phase charger is not possible in the Model S I guess. I think the Model S should be able to charge at 16A (maybe 32A...?) single-phase (230V), this way you can charge at every normal outlet. When you go three-phase you can charge with up to 32A giving you ~20kW of power.

 

[Norbert]

I think the important point for me is that Tesla's 90 kW superchargers do use 3-phase. Otherwise I'll probably wait for for Tesla's "formal response" before discussing this further. That response might make a lot of points moot, depending on what Tesla's actual plans are for Europe (which haven't been announced yet).

 

[widodh]

I think the important point for me is that Tesla's 90 kW superchargers do use 3-phase. Otherwise I'll probably wait for for Tesla's "formal response" before discussing this further. That response might make a lot of points moot, depending on what Tesla's actual plans are for Europe (which haven't been announced yet).

In the US you also have to draw your power from 3-phases, since 90kW single-phase is not going to work anywhere in this world.

Don't underestimate how much power 90kW is!

The problem I have with saying that DC-charging is the alternative for 3-phase charging. Imho it is not, since it is not mobile, so I'm depended on this external device somewhere to charge my Model S, since single-phase is not going to do the job in Europe.

 

[dpeilow]

This is the point in a nutshell.

 

[Norbert]

Once again this not the "let's repeatedly explain how some things are different outside the US to Norbert" forum. If you don't understand by now why Europeans want/need 3-phase, then you probably won't. If you disagree, then fine and leave it at that. Forcing a circular discussion is tantamount to trolling and is getting tiresome.

I perfectly understand the "want" part, I'm just not sure about the extent of the "need" part vs other possible things like external 11kW 3-phase chargers. "Want" and "need" are very different. That is an honest discussion on my part, and I have seen new points and received more information than I had before, so for me this isn't "circular".

To bring the discussion to this extent was meaningful only in so far as there are claims, based on personal conversations posted here, that Tesla (who is already present in Europe) does not plan to support 3-phase.

Obviously this would imply that Tesla would also disagree with the "need" part. So this isn't a closed case, but even before reading you message, as I wrote above, I've decided to wait for Tesla's formal response, leaving this discussion for the time being by pointing out what is important for me:

a) the Superchargers do use 3-phase.
b) there are repeated statements by multiple persons (if not the majority of those who argue vehemently for 3-phase) that with 3-phase, 90 kW DC fast charging isn't important, and this point of view is a major mistake from my point of view.

 

[dpeilow]

Nobody is disagreeing with your point b.

 

[eledille]

b) there are repeated statements by multiple persons (if not the majority of those who argue vehemently for 3-phase) that with 3-phase, 90 kW DC fast charging isn't important, and this point of view is a major mistake from my point of view.

I suppose I am one of those... This is what I have been arguing for years now:

Single phase up to 16 A is important because that's what we will have to use when nothing better is available.

For the reasons given in my previous post, home charging, opportunity charging and destination charging in Europe will be done with 3-phase power.

CHAdeMO at 50 kW will not be able to compete in Europe because 63 A, 400 V charge points are almost as powerful but much less expensive. The availability of 63 A, 400 V charge points will therefore quickly exceed that of CHAdeMO - as long as 63 A, 400 VAC chargers are sufficiently inexpensive. They are, and within a few years, the 3-phase charger will be integrated into the PEM, further reducing the cost dramatically.

100 kW quick chargers is a different matter, they offer much more power than a 63 A outlet can provide. The cost will naturally be higher, and so will the price you pay. Nobody will want to travel to one, pay a premium and wait while charging when they can charge for less while going about their business. But when you need to extend the range and are already on your way towards the next charger along the highway, nothing can beat high power DC. The German infrastructure plan recognizes this, but notes that at the time of writing, no standard had emerged.

I've never argued against support for any DC charger type, or at least, that has not been my intention. As long as they implement the same communication protocol, any DC charger should be trivially simple to support via adapters. What I dislike is public money being wasted on the dead end called CHAdeMO (again, in Europe). Experimentation and test projects is ok to a certain extent. Attempting to build something real based on it is not ok.

And 3-phase support is much more important than DC in Europe. We can build a practical, working EV infrastructure without DC, but not the other way around. That does not mean that we should not have both.

 

[widodh]

I perfectly understand the "want" part, I'm just not sure about the extent of the "need" part vs other possible things like external 11kW 3-phase chargers. "Want" and "need" are very different. That is an honest discussion on my part, and I have seen new points and received more information than I had before, so for me this isn't "circular".

To bring the discussion to this extent was meaningful only in so far as there are claims, based on personal conversations posted here, that Tesla (who is already present in Europe) does not plan to support 3-phase.

Obviously this would imply that Tesla would also disagree with the "need" part. So this isn't a closed case, but even before reading you message, as I wrote above, I've decided to wait for Tesla's formal response, leaving this discussion for the time being by pointing out what is important for me:

a) the Superchargers do use 3-phase.
b) there are repeated statements by multiple persons (if not the majority of those who argue vehemently for 3-phase) that with 3-phase, 90 kW DC fast charging isn't important, and this point of view is a major mistake from my point of view.

Let me reverse the questions.

How would you feel if Tesla would limit the on-board AC charger to 3.6kW (16A@230V) and your only other option is to use Tesla's supercharger.

Without a 'supercharger' you'd be waiting over 24 hours to get your Model S charged.

 

[Norbert]

While I appreciate your willingness to discuss this further with me, it follows from the above messages that I won't, at least until Tesla's formal response is in, if not until Doug changes his mind.

 

[widodh]

While I appreciate your willingness to discuss this further with me, it follows from the above messages that I won't, at least until Tesla's formal response is in, if not until Doug changes his mind.

Great We could postpone this discussion until Tesla responds, but I don't think that will be before the Geneva Motor show in March 2012.

 

[Norbert]

Great We could postpone this discussion until Tesla responds, but I don't think that will be before the Geneva Motor show in March 2012.

I doubt this discussion would be postponed until March with or without me... although that would be fine with me. I'd guess it will re-ignite at the latest in Jan/Feb 2012 when Tesla makes its official SuperCharger announcement.

 

[Eberhard]

i think its a good idea to compare the situations in Europe and America. It looks like, that the NEMA-50 is quite popular in America like the CEE 3x16A is in Europe. I think you wont be happy to have a charger which supports 3x16A but could not do higher currents? or can do 3x32A but not even 1x40A?