Originally Posted by Rovert
he said. at 100 amps I was on the cusp of having insufficient supply.)


In the UK, 100A is the maximum you can have on a single-phase supply, which is what they give to domestic addresses. This enables you to draw 24Kw, which is a flippin' massive amount for a house to use. To go higher you need a 3-phase supply and a commercial contract. I believe in some countries (Germany?) it's much more common to have 3-phase to domestic properties.

I don't actually believe this is that much of a problem though, since the vast majority of EV charging would be overnight. The effect will be to bring the night time base load on the grid much more in line with that of the day time, so if anything it makes it easier for capacity planning as the required load would be more predictable.

The overwhelming majority of EVs will not need to be fully charged every night, most would probably only need topping up every few days. If we take the average 30miles per day and a rule of thumb of 30kWh/100 miles, then for an EV that was plugged in every night a smart charger would only need to bung in around 10 KWh in over say a 10-hour period, which would be no problem for a domestic house supply to cope with. I have a 16A socket in the garage that can support a 3.6kW charger so in theory an EV in the average pattern of use would be charged in 3 hours. A bit of smarts in the controller synced to the smart meter could easily cope with scheduling that charge time to do it when there's lower demand on the grid.

In theory, the south of the UK has got slightly more of a problem because of transmission losses (most of the generation is in the north) but that's taken care of by the grid and the transmission charges. There is however a political/commercial risk in that when we decided to privatise the network we sold nearly all of it to foreign companies, and it's the Chinese who operate the distribution network in the south east. I see that as being a far greater risk to us than the technical challenges of being able to deliver a few more kWh to people's homes.

Tim H.
1986 4/4 VVTi Sport, 2002 LR Defender, 2022 Mini Cooper SE