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Is it technically possible to replace the current standard 11 KW onboard charger?

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DC charging is very expensive to install. Much more expensive than AC charging. So I don't expect it to overtake anytime soon. Better to have the cost built into the car instead of the station to grow the network.

To minimise the cost of the chargers, it makes sense to put the charger in the car if there are more chargepoints than cars; better to put it in the chargepoint if there are more cars than chargepoints.

Your home charger is (normally) going to be used by only one car, so you are committed to having at least one small charger per car - better to put this one in the car so that it can be used elsewhere rather than stuck on the wall at home.

Very high speed charging is always going to be expensive to install, due to the cost of the grid connection, so it has to be used by lots of cars to make it affordable. So in this case, better to put the high power charger in the chargepoint where it will be used by several cars during the day, rather than one in each car that would be used (on average) barely once.

So the only real question is where to draw the line between slow charging (charger in the car, can install loads of chargepoints cheaply so that they are still economic even if used only once in a while), and fast charging (charger in the chargepoint, expensive to install, only affordable in locations that are going to get a lot of use).

"charger in the car" implies AC, "charger in the chargepoint" implies DC.
 
Yeah, okay, you also have option 3, getting the Tesla Type 2 adopted as the DC charging standard for Europe. But I just don't think the Germans are going to accept that.

No matter how many superchargers you have, you will always have situations where charging at public rapid chargers is more convenient.

I couldn't care less about European standards.

No matter how many superchargers there are, there will always be situations where a plug-in hybrid is more convenient, but that's not enough of a reason for me to want one of those.

I also really think you underestimate Tesla's ambitions for the supercharger network. I fully expect them to outnumber the CHAdeMO/CCS charge points in the UK in 3 years time. There are 32 supercharger points (that we know of) in the UK already, vs around 250 CHAdeMO or CCS points, and Tesla have barely started. The installation team who put the Bristol SC in said they were contracted to install 10 more UK supercharger locations by Christmas and they are rumoured to have signed deals with two of the large supermarket chains to put SCs in their car parks.

And finally, while we are currently in a honeymoon period of free rapid charging in the UK at least, this will not last more than another 6-12 months IMO. When an hour at a CHAdeMO point costs £10 but the superchargers are still free I think usage will be even more skewed towards the SC sites.
 
So, future EV's will not be equiped with an onboard charger?

The thing Tesla calls a charger is not just a transformer, but also a rectifier of AC to get DC for the batteries. That device could just as well go at home in your garage rather than in the car, and have a higher capacity with cooling taken care of by fans, etc. But then you'd be giving up all the zillions of AC charging points that exist. If we eventually have a large enough number of quick DC charging points, it will be less necessary to have a "charger" in the car, and the limits of portable "chargers" will be less important, and eventually one might just forget about having a charger/rectifier in the car.
 
No matter how many superchargers you have, you will always have situations where charging at public rapid chargers is more convenient.

But who is paying for those public rapid chargers?

At the moment, the market is distorted by government and other grants - it's not reasonable to suppose those grants will continue once EVs become mainstream.

So, either there will be independent charging vendors (as with petrol stations today), or else rapid charging will be funded by the car manufacturers (as Tesla is doing now, and to an extent the other manufacturers too - Nissan funding CHAdeMO installations).

If the independent operators manage to establish a viable business, then they will be fitting whatever connectors are appropriate to service their customers - so if Tesla vehicles remain a significant part of the market, they will be putting in multi-headed chargepoints with Tesla cables as one of the options, regardless of what "the Germans" think about it.

If manufacturer funding remains important, then the manufacturers will obviously only fund installations that can charge their vehicles - so we get things like the Supercharger network, with potentially similar networks from other vendors, but possibly also bribing independent operators to install more of their favoured connector type. Nissan's CHAdeMO installs at dealers (and Renault's similar high-power AC) are an interesting case - Nissan would clearly like to treat it as a manufacturer network and only charge Nissans there, in which case the fact that CHAdeMO is 'open' doesn't matter, but maybe the dealers see a chance to make money from selling power to non-Nissan cars and so act more like an independent operator.

It also needs to be born in mind that so far only Tesla's superchargers have a defined business model that potentially scales to large volumes. Tesla may or may not have got their calculations right (can they afford to fund a sufficiently large network from the margins on Model 3?), but they have a plan. Most of the other rapid charging has totally fudged the economics to get started - reliant on government grants, on leaching off existing electrical supplies rather than paying for new (which can't continue as things scale up) and in many cases saying 'free for now' with no clear idea how 'not free' is going to pay for continued expansion and maintenance.
 
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I couldn't care less about European standards.

No matter how many superchargers there are, there will always be situations where a plug-in hybrid is more convenient, but that's not enough of a reason for me to want one of those.
A plug-in hybrid is an alternative to an electric car, whereas better charging is an augmentation to an electric car. Switching to a plug-in hybrid means dispensing with all the good qualities of an electric car, while better charging (as an option) has no downsides.

It's important to look beyond the Model S, beyond the Model X, perhaps even beyond the Model 3. People will want charging available ideally anywhere they might stop while on a longer trip. It isn't enough to have supercharging every few dozen miles, when people want to stop at a specific restaurant that might have an incompatible rapid charger. Avoiding that situation would be a good thing.

I also really think you underestimate Tesla's ambitions for the supercharger network. I fully expect them to outnumber the CHAdeMO/CCS charge points in the UK in 3 years time. There are 32 supercharger points (that we know of) in the UK already, vs around 250 CHAdeMO or CCS points, and Tesla have barely started. The installation team who put the Bristol SC in said they were contracted to install 10 more UK supercharger locations by Christmas and they are rumoured to have signed deals with two of the large supermarket chains to put SCs in their car parks.
When talking about the utility of the supercharging network, the number of locations is just as important as the number of chargers. Even looking forward to 2016, the UK will have around 23 supercharger locations (according to the map), which the CCS/CHAdeMO outclasses with ease even today. I feel quite comfortable saying that the number of supercharger locations will never rival the number of CCS/CHAdeMO locations, for several reasons:

1. Tesla strictly speaking doesn't need to put up superchargers closer than 200 miles from each other. For CCS/CHAdeMO, this figure is closer to 50 miles. So, you basically need four times as many CCS/CHAdeMO as tesla superchargers for equivalent utility.
2. Teslas don't have any need to charge on trips up to 200 miles, the equivalent figure for other EVs is around 50 miles. Now, I don't have detailed statistics showing the percentage of trips that are 50-200 miles vs 200+ miles, but lets say the need for rapid charging on low-range EVs is three times as high.
3. Tesla doesn't have 50% of the market. If you look at Norway, you'll probably have sold around 70,000 electric cars by the end of 2015, and of these, maybe 10,000 will be Teslas. This gives Tasla a market share of ~15%, and this is in Norway. (We love tesla.) If other electric cars outnumber Teslas 7:1, you'll need 7 times as many chargers.

4 x 3 x 7 = 84

You'll need around 84 times as many CCS/CHAdeMO rapid chargers as Tesla Superchargers, for an equivalent coverage. Of course, you can probably adjust this figure somewhat to account for people needing to drive long distances choosing to get a Tesla instead of a Leaf, e-Golf or something, but it's not unlikely that CSS/CHAdeMO will outnumber Tesla Superchargers 40:1 within a few years.

And finally, while we are currently in a honeymoon period of free rapid charging in the UK at least, this will not last more than another 6-12 months IMO. When an hour at a CHAdeMO point costs £10 but the superchargers are still free I think usage will be even more skewed towards the SC sites.
The CCS/CHAdeMO/Type 2 chargers we have here aren't free. But situations will undoubtedly arise where the nearest supercharger is 10+ miles away, but you have a CCS/CHAdeMO/Type 2 right where you are, and it makes more sense to pay to use it.
 
long story
Couldn't agree with you more!

Expand the horizon indeed, look beyond S, X and Model 3.

CHAdeMO will probably die out, but CCS is there to stay. I'd rather charge at a CCS location which saves me time then go to a free SuperCharger.

But to get back to the point of this topic, I share the vision that DC is the future and AC will only be used for charging at night.
 
Also my understanding is that current CCS implementation (i.e. the connectors) max out at 125A DC. Since a Model S charges at around 360V that's only 45kW. Where did you get the idea that CCS would allow 200kW charging?
It's my understanding the pins can actually handle 200+ Amps, but the current implementation is limited at 125A. The current Tesla Type 2 can handle something in the area of 320A, so if you add 200A over the DC pins, thats max around 520A. That would be 187 kW. These are just ballpark figures, but you get the point.

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Couldn't agree with you more!

Expand the horizon indeed, look beyond S, X and Model 3.

CHAdeMO will probably die out, but CCS is there to stay. I'd rather charge at a CCS location which saves me time then go to a free SuperCharger.

But to get back to the point of this topic, I share the vision that DC is the future and AC will only be used for charging at night.
I don't entirely agree. My view is that AC will fulfill the needs for charging at night, but also the needs for destination and opportunity charging. Basically the range of 1-43 kW.

DC will fulfill the needs for really fast charging. 50-500 kW.
 
It's my understanding the pins can actually handle 200+ Amps, but the current implementation is limited at 125A. The current Tesla Type 2 can handle something in the area of 320A, so if you add 200A over the DC pins, thats max around 520A. That would be 187 kW. These are just ballpark figures, but you get the point.

No it's the other way around. The protocol defines how to negotiate for up to 200A of current, but the DC pins on the current CCS connector are only rated for 125A.

We have no idea what the actual current limits on either US or EU Tesla-proprietary connectors is. The limit on supercharging speed today is almost certainly the batteries anyway, and to a lesser extent the physical act of connecting the charge cable. Even the current 120kW is only possible when at low state of charge, so a 200kW charger wouldn't materially improve charging times. Rather than 20 minutes for a half charge, 40 minutes for an 80% charge and 80 minutes for a full charge it would be 15, 35 and 75. That really doesn't make the slightest difference, does it? And the cable on a 200kW supercharger would be so heavy and inflexible that I think some owners would genuinely struggle to use it.

Anyway if you wanted to get 240kW into a single Model S then the obvious solution is just to fit a second charge port on the other side and then connect them both up. But like I said, the battery is limiting.
 
No it's the other way around. The protocol defines how to negotiate for up to 200A of current, but the DC pins on the current CCS connector are only rated for 125A.

We have no idea what the actual current limits on either US or EU Tesla-proprietary connectors is. The limit on supercharging speed today is almost certainly the batteries anyway, and to a lesser extent the physical act of connecting the charge cable. Even the current 120kW is only possible when at low state of charge, so a 200kW charger wouldn't materially improve charging times. Rather than 20 minutes for a half charge, 40 minutes for an 80% charge and 80 minutes for a full charge it would be 15, 35 and 75. That really doesn't make the slightest difference, does it? And the cable on a 200kW supercharger would be so heavy and inflexible that I think some owners would genuinely struggle to use it.

Anyway if you wanted to get 240kW into a single Model S then the obvious solution is just to fit a second charge port on the other side and then connect them both up. But like I said, the battery is limiting.
Again, I'm thinking beyond the current models. In 10 years the largest battery might be 150 kWh and able to handle 2C, so max 300 kW. Such a battery might easily be able to handle 200 kW up to 70% SOC, or about 250 miles of range in 30 minutes. The battery is the limitation now, but that won't remain the case for long.
 
(LMB spouse)

Another option is to design higher voltage batteries. I think US electrical codes have different (and more severe) requirements above 600 volts, but say a 560-ish volt battery instead of 400 volts. Now max charging power is 320 amps times 560 volts or about a 180 kilowatt max charge rate for those bigger future batteries.
 
Again, I'm thinking beyond the current models. In 10 years the largest battery might be 150 kWh and able to handle 2C, so max 300 kW. Such a battery might easily be able to handle 200 kW up to 70% SOC, or about 250 miles of range in 30 minutes. The battery is the limitation now, but that won't remain the case for long.

Tesla's Superchargers are hardware limited. Not that they can't be upgraded, but I remember reading some comments here of people that saw the wire size they use underground. They were limited to something around 400 Amp. Unless Tesla wants to rip out and replace all the underground cables from all Superchargers, that's what the hard limit is. Not sure what the hard limit is on voltage. Higher voltage would allow more power with the same cable size.