How much total power is available to a typical UK residence?
The power cable coming into your home terminates in a cut-out box. Inside that little black box is a 80 or 100 Amp fuse. (E.On manual Page 21, last row in Table 1.2.3)
Watts = Amps * Volts: 220V * 100A = 22kW. If the house draws more than 22kW from the network, the fuse will blow.
22kW is an upper limit. What is available to charge a car is considerably lower.
There are two reasons for this. First, that 100A fuse is as a last resort to protect the LV distribution network. Design power is lower. Second, other devices in your home are consuming power.
The big power consumers in a house are electric heaters and major appliances. You can safely ignore cell phone chargers, clock radios and things like that. Combined they use maybe a few watts.
In our home the major consumers are:
: 7kW Electric Showers can use as much as 10kW
Hot Water Cylinder Immersion Heater
3kW * 2. For some reason, our cylinder has two of them.
2.3kW (not all the time though)
2kW * 3. (not all on at the same time)
??? A+++ rated, but it might draw 2kW when cooling
??? Can't find spec, but about 2.5kW
up to 6.6kW, but closer to 3kW in typical use.
Add all of these up and it is obvious we can't have everything on at once, even with out an EV charger.
Typical 100A 1 Phase power install ---