I've toyed with the idea of an electric car but don't have one yet.
Octopus Energy have a deal where you can charge up overnight at a low rate (5p per kwh last time I looked).
If you have battery storage for use for the house, you can top your batteries up at that price as well so that you don't need to buy much from the grid for most of the year. You can also take advantage of times when , believe it or not,
they pay you for using electricity from the grid. It's been either free or less for most of today up to 4pm so, today, I haven't paid for any electicity that I've used and I have 9.6 kwh in the batteries to last me until tomorrow when the sun (hopefully) shines again. I have an app that lets me control when/if I charge my batteries from the grid and I have an app that tells me the cost of electricy half-hourly from Octopus for the next 24 hours.
I have a roof that faces east/west and have two arrays of eight panels and 9.6kwh of battery storage.
I pay £50 a month for my energy and am currently £1,500 in credit - and the summer days are just starting.
So, even with without the cheap rate for car charging, the panels/batteries will have paid for themselves by the end of this summer. They were installed in May 2019.
I only had 2.4kwh of battery storage for the first couple of years but I got offered a good deal for three more so grabbed it.