@KP85E13 and @kezo Thanks very much, people. If only BG would let me have that data I need not have bothered you. (Tried that link, kezo but it just puts me on a page for switching ordinary tariffs, absolutely nothing for ev tariff. Will need to do my sums properly but it looks like switching to ev tariff will cost me more than paying standard day-rate for the car.
Thanks again, folks. Most helpful. 😊