ID3 1st & e-Golf
What else do you have running on electric in your house, the heating?Yes. And no. You can only have the amount your incoming fuse is rated for. And I’ve not seen one rated at more than 100A on a single phase supply. More may be possible, but I’ve never come across one.
Of that 100A you can take up to 32A for the 7.4kW charger. If you add a second charger on the same 100A main fuse, you will have two chargers running at 3.6kW, which is better than nothing, but not a great advance on the 2.4kW most granny chargers give you.
I was faced with exactly this scenario at home (also my office) and I paid a little over £2000 to have the electricity supply upgraded to 3-phase and I then had a dual Type2 Pod-Point 3-phase pedestal charger installed (£1299+VAT after all applicable grants were applied), so each car charges at 11kW. If we had a car that could charge at 22kW then in theory if we only plugged in one car it would charge at the full 22kW rate.
You can see this in action on the Pod-Points installed at Tesco’s stores where one car plugged in gets about 6.5-7kW but when a second car is plugged in to the other side of the charger, both cars drop to 3.6kW charging rate.
If you can get a main fuse bigger than 100A on a single phase then this doesn’t apply, obviously.
I have a 100amp fuse and two 32amp charge points that both charge at the same time.
That's only 64amps so there's still 36amps left for the rest of the house.
The Zappi monitors the overall load of the house and will reduce the current going to the cars to keep within the limit of the fuse.
You could have installed a zappi and not upgraded to a 3 phase supply.