Chargepoint CT4000 - Share one 40A circuit with 2 chargers

[Deleted member 8423]

(I searched, and was surprised to not find any threads discussing this new charger, let alone this "innovative" new feature)

http://www.chargepoint.com/products-chargepoint-stations.php" onclick="window.open(this.href);return false;

From the spec sheet: "Dynamically share one 40A circuit between two parking spaces"

This seems to present an interesting scenario. Your session starts with you as the only car connected to the charger. So you are pulling down the full 6+ kW. Then later another car connects, so suddenly you're pulling closer to 3.3kW. All of the Chargepoint stations that I've seen bill by the minute (or are free), not by kWh. This means that you could effectively end up paying twice as much for the charge.

You'd have to be really up to date on EVSE tech to know that this would happen. So at best, it's going to be confusing for users.

Has Chargepoint mentioned a desire to move towards kWh-based billing where possible? If not, how do you think they plan on handling these sorts of situations?

 

[DaveEV]

Looking at the spec sheet, it looks like when it's set up for sharing, you only get 16A max out of each port - there is no dynamic allocation of current depending on how many plugs are in use (though that'd be cool).

Edit: I may be wrong above, it does say 1x30A OR 2x16A output in a sharing configuration, so that does imply that you can get more power if only one plug is in use... BTW, I think that Chargepoint is able to charge by the kWh...

 

[swaltner]

Kind of interesting in that it can improve the number of plugs available for the same installation costs (for the electrical work at least). Just brace yourself for the "complaints" from the Tesla owners. A 3 kW power feed when charging a 60-85 kWh pack is basically worthless, so I would feel their pain. This would be OK for a hotel or some other overnight destination to use. Overnight, you could still get a fairly decent charge. A Tesla wouldn't necessarily be able to fully charge overnight, which is why it doesn't really help them.

They don't explain how they dynamically share the available power. If you were already plugged in and charging at 6 kW and another vehicle plugged in, I think it would be best if it didn't drop your charging rate to accommodate the new vehicle. Once the first vehicle's charging session completed, it could switch power over. If you plugged in after a Tesla, you would be SOL for a while. However, if you had two Leafs plug in, even with fully depleted batteries, they could both be charged overnight. The only difference to this would be if the first vehicle was only charging at 3 kW, make the remaining power immediately available to the second vehicle. That's how I would like it to behave at least.

 

[Randy]

I also notice that the price for this double-headed unit with power sharing is conspicuously absent, which leads me to believe that it is several thousand dollars each or higher...Not exactly economical when you're putting in a few of them in a parking lot....

 

[Deleted member 8423]

If you were already plugged in and charging at 6 kW and another vehicle plugged in, I think it would be best if it didn't drop your charging rate to accommodate the new vehicle. Once the first vehicle's charging session completed, it could switch power over.

If I were the person that was already plugged in, I'd think this was best too. But what if you were the 2nd person plugging in? Your charge might not start for hours, depending on how long the first one needs to complete its charge. Probably not an acceptable option in most scenarios where these chargers would be found (i.e. retail locations). This is the way the Blink DCFC's work today, but that only "works" for folks because the time to charge is relatively quick.

This might be fine for home users who are looking for a better solution that requires only 1 40A circuit to charge multiple cars. But that's not the target market for these.

I also notice that the price for this double-headed unit with power sharing is conspicuously absent, which leads me to believe that it is several thousand dollars each or higher...Not exactly economical when you're putting in a few of them in a parking lot....

Agreed that it's not a good sign. And all online searches turn up just the press release and one other article written about the unit. However, since they're heavily touting the economic benefits of this charger, seems likely that they'll keep the pricing close to (or perhaps below) the cost of their current dual-headed units.

 

[EVDRIVER]

This is an overdue product and makes sense for public charging. The goal is simple, allow to vehicle charging were the supply power is limited and/or where one wants to have more chargers available. This is a very common problem at some locations and it allows many benefits. I would certainly prefer 3kw VS none and also the opportunity for 6kw once another car goes off. The cost of this unit will likely be very high initially.

 

[smkettner]

I agree TWO Teslas may have trouble but at least they are connected. The idea is to have more positions to charge. So when the Volt or Prius is done in one hour your Tesla can have all the current vs CANNOT EVEN CONNECT because the Volt/Prius was there first and occupies the one spot all night.

If the hotel has frequent Tesla patrons a Tesla connector would probably be preferred and let the lesser vehicles fight over the dual head evse.

 

[EVDRIVER]

I agree TWO Teslas may have trouble but at least they are connected. The idea is to have more positions to charge. So when the Volt or Prius is done in one hour your Tesla can have all the current vs CANNOT EVEN CONNECT because the Volt/Prius was there first and occupies the one spot all night.

If the hotel has frequent Tesla patrons a Tesla connector would probably be preferred and let the lesser vehicles fight over the dual head evse.

I see Teslas parked in SF parking garages occupying charge spots all day every day, after day. I see one in the same slot every single day all day long at one garage, may as well put their name on the spot :roll: The irony is I really doubt they need that charge. Right next to this was a PIP that was in the charger for at least 4 hours so I think we need quad units actually.

 

[davewill]

... I see Teslas parked in SF parking garages occupying charge spots all day every day, after day. I see one in the same slot every single day all day long at one garage, may as well put their name on the spot :roll: The irony is I really doubt they need that charge. Right next to this was a PIP that was in the charger for at least 4 hours so I think we need quad units actually.

Let me guess, free charging?

 

[smkettner]

Soon there will be 10, maybe 50+ on a network to share power.

 

[EVDRIVER]

... I see Teslas parked in SF parking garages occupying charge spots all day every day, after day. I see one in the same slot every single day all day long at one garage, may as well put their name on the spot :roll: The irony is I really doubt they need that charge. Right next to this was a PIP that was in the charger for at least 4 hours so I think we need quad units actually.

Let me guess, free charging?

Of course!

 

[LEAFer]

... I see Teslas parked in SF parking garages occupying charge spots all day every day, after day. I see one in the same slot every single day all day long at one garage, may as well put their name on the spot :roll: The irony is I really doubt they need that charge. Right next to this was a PIP that was in the charger for at least 4 hours so I think we need quad units actually.

Let me guess, free charging?

Of course!

And how much are they paying for parking ? ( I am assuming they have a cheaper location to park at ... )