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

[Lloyd]

I have not seen or heard of anyone doing that (yet). I think the electrical signals are fine and "good to go", but the problem is the Tesla socket you would need.
Some Tesla HPCs have been permanently converted to J1772 by chopping off the Tesla plug and replacing it with a J1772. Then you could buy the Tesla J1772 to Tesla adapter cable and do it that way. But if you want to leave it "native Tesla", you would need to find a Tesla socket. I don't know if Tesla will sell you one. Maybe someday someone will convert their Roadster to native J1772 and have a spare Tesla socket to sell. (Tomsax did that temporarily, but I think he put his Tesla socket back on the car again.)

You want the "inverse" of this:

With "female" Tesla and "male" J1772.

Yes, I want the inverse of what Telsa sells. I would hate to plug someone's Volt or Leaf in and have it implode with 70 amps of power!

[scott451]

Does anyone make an adapter for the Tesla HPC to J1772? I just bought an HPC and would like to be able to charge J1772 vehicles also.

Can this be done safely? Will the pilot signal get passed through, and is the HPC able to respond to this??

Probably the easiest way of doing this (assuming you already have the J1772->Tesla) is to convert your HPC to J1772. The cable costs ~$350 from Avnet. I'll be doing the conversion shortly with my HPC. Now after the conversion you'll have a 70A J1772. The J1772 70A cord is much lighter than the HPC 70A cord.

[Tommy]

Probably the easiest way of doing this (assuming you already have the J1772->Tesla) is to convert your HPC to J1772. The cable costs ~$350 from Avnet. I'll be doing the conversion shortly with my HPC. Now after the conversion you'll have a 70A J1772. The J1772 70A cord is much lighter than the HPC 70A cord.

Link to Avnet's product page page:

Avnet Electronics Marketing - ITT Interconnct Releases SAE J1772 Connector Solution

[TEG]

Yes, I want the inverse of what Telsa sells. I would hate to plug someone's Volt or Leaf in and have it implode with 70 amps of power!

No need to worry about that. The HPC/EVSE would send a signal to the Leaf and say "you can have up to 70amps", and then the Leaf would start pulling 16A (which is the max the current charger in the Leaf can draw) and have no problem with it. Having higher current capability doesn't cause a problem. Some vehicles won't take full advantage of it though because they have 'wimpy' chargers.

[Norbert]

But I am back to thinking that Eberhard is/was suggesting residential 3 phase by stating concerns over unbalanced grids and increased average (per house) consumption. Perhaps it isn't the ideal answer, but some of those concerns could be addressed by putting bigger transformers to neighborhoods.

For residential areas where phases might get split apart, one important method to address this will be using smart grid capable EVSE. This, I think, is one of the reasons the DOE pushes smart grid EVSE. Together with time-of-day charging, these allow utilities (to some degree) to balance the load by controlling the time (within the off-peak period, during the night) at which EVs in a neighborhood start and stop charging, and to turn them off if really necessary to prevent a black out (in which they could not charge either). In my mind, EVs capable of a higher charging speed should give the utilities more flexibility in balancing the load, since they don't have to charge most of the night, and thus give more options in choosing the time to charge them, if you know what I mean.

This will reduce the number of cases where bigger transformers need to be installed. And perhaps even more importantly, to remind, charging in residential areas is mostly off-peak, at times when there is much less stress on the grid. Also, the utilities could surely further improve load balancing by having areas that can be switched to any of the 3 phases as needed to balance other areas. That shouldn't be difficult, even if requiring a change in how the areas are connected to the transformers. I guess.

[TEG]

Yeah, I follow you... Well, the part about selective phase switching seems like it might be a bit 'far fetched', but I don't really know for sure.

Yes, 'smart grid' EVSE with remote disconnect to reduce load or maintain balance as needed seems to be in the works.

[Norbert]

Well, the part about selective phase switching seems like it might be a bit 'far fetched', but I don't really know for sure.

OK, in case that doesn't work well for some reason, here another idea:

We've heard that the utilities in the US, even though they don't usually install 3-phase in residential areas, can still do so if asked for. So, for example, close to each transformer with which they might have difficulties in load balancing, they could add 3-phase service to a number of residences, and for the EVs in these residences, install special EVSE. These would work like other J1772 EVSE off a single phase, but in addition to other smart-grid abilities like remote-on-off, it would have remote-choose-which phase-to-run-off. So they would have a certain number of EVSE which they can assign to any phase, and use that to balance the load-per-phase. If something like that is really necessary, it should be an affordable thing(for the utilities) to do.

Problems solved?

[GSP]

"Problems solved?"

Maybe, but a three phase charger would be a much more elegant solution.

Perhaps use the DC fast charge port with an "slower" 5-15kW 3-phase off-board charger. The main (only?) benefit would be a balanced load for the utility.

GSP

[TEG]

Some quotes from a friend who works in the EV charger business in the USA:

I think the three phase balance issue may be bogus. Most neighborhoods I've seen only have single phase feeders from the substation out, so the balance is between large numbers of blocks of houses. The only three phase that is common on poles seems to be in industrial or mixed use areas. Changing houses to three phase would be tremendously expensive.
...
Maybe newer subdivisions are different...

[dpeilow]

There is a good chance you didn't mean it, but this appears to imply (in the context of the statements you refer to) that you are talking about a PEM version which would use 3-phase to replace DC charging. However that would be ignoring the fact that even the Mennekes standard uses DC for fast charging at the levels at which Model S, and future cars, are likely going to use it. 3-phase is not going to make DC obsolete, as was argued above, not even in Europe. (And neither are there any signs that inductive charging would come to that level). This feels like the after-effects of RWE marketing blown out of proportion. I'd rather RWE work on developing low-cost DC chargers (of various power levels), as building a DC network wouldn't really be that expensive in any case.

If I was being greedy, I'd want to be able to charge at 44kW on three phase, 50kW on CHAdeMO and 100kW on whatever Tesla chooses to get the advertised charge time. We are literally seeing all of them being rolled out. If I had to drop one it would be CHAdeMO.

And this is not RWE (or anyone else's) marketing blown out of proportion. We now have close to 5000 Mennekes charging posts announced for the coming year in the UK alone. The AC equipment is one or two orders of magnitude cheaper than DC.