Including generator efficiency and transmission losses, electric cars use about half the energy per 100 km. For a tesla model 3 it takes about 16.7 kWh / 100 km from the battery, and 33.3 kWh of gas / 100 km assuming a CCG generating power with typical transmission losses for the UK and 90% charging efficiency. The corresponding value for a diesel jag (2.0l XE, RWD) is 65.3 kWh / 100 km*. We've been over this every time electric cars come up at hexus, pollution at source is a red herring - there's no comparison to IC car emissions.
*fuel/power consumption from the US EPA, since they make the comparison easy