We've ordered two electric vehicles, and we're entitled to two home charge points, as shown here:
https://www.britishgas.co.uk/energy-saving-products/electric-vehicles
The charge points are now 7kw/32amp (up from 3kw/16amp), so if we have two in use at the same time, that's 64amps!(?).
When I spoke to British Gas, they said 2x7kw chargers should be fine if we have "two 100amp isolators", and if we don't, this is something that could be done (at a price) and I should speak to an electrician.
Before I do, I want to make sure I understand exactly what's required.. By "two 100amp isolators" I presume he's referring to the things we have two of here marked "RCD Controlled Circuits" (both rated 80amp).
Totals for the two sides here are:
- Left: 6+6+16+32 = 60amps
- Right: 6+16+32+32 = 86amps
"Water Heater" presumably refers to the immersion heater that will hopefully never need to be used. We have no electric shower. Oven ("Cooker", 32amp) is electric though hobs are gas.
What's the best way we can connect two 32amp EV chargers here?
Best Answer
The most important thing to check is probably the size of the main supply fuse on your incoming feed. Between 60 and 100 amps is typical for a domestic supply. If you have a 60 amp fuse, I'd be very wary of trying to run two chargers at 7KW each simultaneously.
The other thing to consider is the actual consumption of the chargers that will be connected. Just because the supply point is rated to 7KW, doesn't mean that the charger will actually draw that.
You don't need to accommodate the full current capacity of all the breakers because you're unlikely to be using everything that you possibly can at any one time, but if your peak load exceed the main fuse, you have a problem.
Personally, I'd be very tempted to have nothing further to do with British Gas and approach a local electrician about the work. If their electrical work is priced like their plumbing, it'll be very expensive. (And I wouldn't be surprised if they subcontract it out anyway).