2 chargers speed?

[Smog]

So this ain’t exclusively to Tesla chargers, but I think I’m going with a podpoint tethered 7kw for my expected model 3.

the OH has just today found out she needs a new car. Through work she’s been offered a E-Tron, which she likes and is the right size at a bargain price. They’re even throwing in another podpoint.

just wondered how having two different chargers works, is their still a drain on power of if they’re both 7kw are we fine? Because of the overnight trickle, and our low mileage, I’m not too fussed if it slows a little, but if it takes it down to 3pin speed I’ll just not buy the 2nd podoint and alternate the cars

 

[Mf03]

So this ain’t exclusively to Tesla chargers, but I think I’m going with a podpoint tethered 7kw for my expected model 3.

the OH has just today found out she needs a new car. Through work she’s been offered a E-Tron, which she likes and is the right size at a bargain price. They’re even throwing in another podpoint.

just wondered how having two different chargers works, is their still a drain on power of if they’re both 7kw are we fine? Because of the overnight trickle, and our low mileage, I’m not too fussed if it slows a little, but if it takes it down to 3pin speed I’ll just not buy the 2nd podoint and alternate the cars

From an electrical point of view they should both deliver 7kw if they are independent of each other. I.e. not linked electronically with any load sharing software. Unless others tell me differently,

 

[MrBadger]

DNO may want to have a say on a second charge point. First one, they pretty much have to grant permission (some rare exceptions), but second one is not a done deal - individual circumstances apply.

Might be a reason the e-Tron is a bargain price I seriously considered one and, same with the iPace, charging and range practicalities took precedent. Individual circumstances apply.

 

[Smog]

DNO may want to have a say on a second charge point. First one, they pretty much have to grant permission (some rare exceptions), but second one is not a done deal - individual circumstances apply.

I know it’s individual cases but what kind of circumstance? Our house is 2.5 years old so electrics should be up to it

 

[arg]

Power sharing is not a feature that PodPoint advertise on their units for domestic installations - though the do have it on the similar-looking equipment they use in large commercial installations. You should definitely clarify this before getting your first one installed, as otherwise you may not be able to have a second one.

If your house electrical supply has large capacity (and you aren't already using it for lots of heavy loads in the house), then you might be able to have two independent units (ie. both able to deliver full power at the same time), but that's not typical.

If you do need power sharing (and Podpoint are unwilling to provide it), there are plenty of units that can - the Tesla WC (and yes this will work with other cars not just Teslas), EO, eVolt, Zappi and probably others. For the Tesla unit at least you need two of the same; some of the others may be able to work alongside a standard unit (like the PodPoint), though the sharing will be less fair.

For a pair of cooperating units like the Tesla, the sharing works that if both cars are plugged in and both want to charge, they get half the standard speed (so 16A - still significantly faster than the 10A of a UMC plugged into a 13A socket), then as soon as one car has finished charging, the second one gets full power.

If you have one unit (eg. PodPoint) which doesn't support sharing, and another unit like the Zappi that does demand monitoring, the first car (on the PodPoint) would get full power, and the 2nd car would get what is left over - again going to full power once the first car has finished charging.

 

[Smog]

Power sharing is not a feature that PodPoint advertise on their units for domestic installations - though the do have it on the similar-looking equipment they use in large commercial installations. You should definitely clarify this before getting your first one installed, as otherwise you may not be able to have a second one.

If your house electrical supply has large capacity (and you aren't already using it for lots of heavy loads in the house), then you might be able to have two independent units (ie. both able to deliver full power at the same time), but that's not typical.

If you do need power sharing (and Podpoint are unwilling to provide it), there are plenty of units that can - the Tesla WC (and yes this will work with other cars not just Teslas), EO, eVolt, Zappi and probably others. For the Tesla unit at least you need two of the same; some of the others may be able to work alongside a standard unit (like the PodPoint), though the sharing will be less fair.

For a pair of cooperating units like the Tesla, the sharing works that if both cars are plugged in and both want to charge, they get half the standard speed (so 16A - still significantly faster than the 10A of a UMC plugged into a 13A socket), then as soon as one car has finished charging, the second one gets full power.

If you have one unit (eg. PodPoint) which doesn't support sharing, and another unit like the Zappi that does demand monitoring, the first car (on the PodPoint) would get full power, and the 2nd car would get what is left over - again going to full power once the first car has finished charging.

Very informative thank you. The problem is, a podpoint is free with the Mrs car, so no way would I buy two tesla chargers when I’m being given one and installation for free. Looks like I may buy a demand monitoring one then, if they don’t allow for sharing, and then when the podpoint comes just make sure that’s used for the car with the lowest range.

 

[arg]

I know it’s individual cases but what kind of circumstance? Our house is 2.5 years old so electrics should be up to it

In some areas, DNO's general policy - some won't fit more than an 80A fuse for single phase, and so that pretty much rules out two simultaneous chargepoints (64A) unless the rest of your house uses remarkably little.

In other areas, how many of your neighbours already have chargepoints (I don't actually have evidence of DNOs doing this yet, but in theory they collate all the forms they get when anybody installs a chargepoint, and if they get too many then they will start refusing second chargepoints).

Bear in mind that the supply to a typical housing estate is planned on the basis of about 2kW per house of continuous capability, even though the individual houses have 18kW (80A) or 23kW (100A) supplies - the assumption is that typical usage is only for a modest period of time, and is highest in winter (when the equipment can take more load without risk of overheating). EV charging breaks this assumption by taking large load for many hours at a time.

 

[Smog]

In some areas, DNO's general policy - some won't fit more than an 80A fuse for single phase, and so that pretty much rules out two simultaneous chargepoints (64A) unless the rest of your house uses remarkably little.

In other areas, how many of your neighbours already have chargepoints (I don't actually have evidence of DNOs doing this yet, but in theory they collate all the forms they get when anybody installs a chargepoint, and if they get too many then they will start refusing second chargepoints).

Bear in mind that the supply to a typical housing estate is planned on the basis of about 2kW per house of continuous capability, even though the individual houses have 18kW (80A) or 23kW (100A) supplies - the assumption is that typical usage is only for a modest period of time, and is highest in winter (when the equipment can take more load without risk of overheating). EV charging breaks this assumption by taking large load for many hours at a time.

so I’ve just had a look and I think we may have 2 phase (if that’s a thing). The upstairs is listed as 64a and the downstairs as 80a. Would it be more reasonable to get a 7kw and a 3kw charger then? Surely that would work better?

 

[arg]

we may have 2 phase (if that’s a thing)

2 phase isn't really a thing (there's single split phase as used in remote locations, typically farms, which you could think of as 2 phase though it isn't called that). However, a 3-phase supply with only two phases actually in use is not that unusual - it's what tends to get done if a house needs just a little bit more than a standard single phase supply. I'm still a little surprised to see it in a 2.5 year old house unless it's huge - more often seen in older houses that have (or used to have) electric heating.

If that's really what you have, then various options open up, including a 3-phase chargepoint for somewhat faster charging, though the cost of the extra switchgear to actually get that connected up is probably not worth it. Activating the third phase and using it entirely for charging is another option, as is squeezing in the chargepoints on whichever of your two phases is least loaded, or one on each.

The costs here are very hard to estimate - relatively trivial aspects of how your existing setup is wired could make one option or the other unreasonably expensive.

 

[Dilly]

so I’ve just had a look and I think we may have 2 phase (if that’s a thing). The upstairs is listed as 64a and the downstairs as 80a. Would it be more reasonable to get a 7kw and a 3kw charger then? Surely that would work better?

I had an 80 amp supply which DNO uprated to 100amp.
I have 2 Zappi chargers and two Powerwalls.
You can have two 7Kw chargers and if necessary, limit one or the other as needed in their settings

 

[Asterix187]

We have a Model S and a Hyundai Kona. The wife charges once a week and i Charge twice a week. Unless you are both doing high mileage you should never actually need to charge at the same time.

 

[WannabeOwner]

wondered how having two different chargers works

I would be looking at the "charging profile" the two cars needs. What's the "averagely worst scenario" where both cars are on long journeys, at the same time. Maybe eTron will only trog backwards/forwards a few miles to work?, and would charge over night in a couple of hours? In which case it could be scheduled for "after the main one", or "both at 2AM - 4AM" when you / the local houses won't be power-showering and cooking Christmas dinners ...

If you don't have load balancing chargers how often will you be mucking about with manual scheduling to avoid having both on at once? would that be an annoyance for you? or maybe you just dial down the AMPs on Tesla (maybe you can do that on eTron too?) to do your own load balancing. They won't ramp back up by themselves when first one finishes, but if both cars will be fully charged overnight, at lower AMPs, that would be fine (bit less efficient ... but ...)

My biggest annoyance is when I have to do anything non-standard like this and forget / muck-up / lead it like that the following night(s). You COMMs with wife may be far better than mine in that regard!!

If your house electrical supply has large capacity (and you aren't already using it for lots of heavy loads in the house), then you might be able to have two independent units (ie. both able to deliver full power at the same time), but that's not typical.

Something perhaps to chuck in the mix is also overnight-charging a Powerwall ... or two.