The problem with electric vehicles in the UK
Is access to charging points. I have to park on-road at night, so unless I want to try and run a cable out of my front window (as I've occasionally seen people do!), there isn't any way for me to charge an eCar. And even that depends on being able to park directly outside my house.
Though saying that, the percentage of households with this issue is lower than I expected - according to an RAC report from 2012 (https://www.racfoundation.org/wp-content/uploads/2017/11/spaced_out-bates_leibling-jul12.pdf), only around 25% of car-owning households have to use on-road parking - though they do note that this rises to 60-70% in dense suburbian areas.
And even if you do have off-road parking, if you want to be able to charge your car in a reasonable time frame, you'll need to get a charger installed, which looks to be around £750 (admittedly, minus a £500 OLEV grant from the government).
Certainly, until/unless I move to a house with a garage, the odds of me buying an eCar are pretty low...