I've always had a fascination for infra-structure and there's plenty of data available regarding the UK Electricity Grid  Hiding away there is a database of all the power sub-stations in the local area, including an assessment of the capacity of each with regard to the number of electric car charging points already connected. These are designated by the National Grid as 'Limited' (shown in Red), 'Extensive' (Green) or just 'Capacity' (Yellow). 

So, to plot these on a map - some Python coding was required to clean and tidy the original data, then I created a KML file to show the locations on Google Earth. A little snippet is from the map is shown on the right.

Conclusions? There's probably enough generation capacity nationally as overall energy use has been falling since the 2000s, but there will be some local upgrades required in rural areas. On a personal level our 50kW sub-station is connected to about 20 households, with 4 electric cars chargers. If all 4 cars are being charged at 7.2kW, plus another 1kW per household, this is nearly up to the capacity limit of the transformer!