It might need to be the subject of some research to fully address this, as you say - especially voltage variations such as "brownbouts" and other network events.

Agreed! I wonder if anyone has any power analyser logs lying around that might help?

I wonder too how common "brownouts" are in the UK (unlike place like the US where they seem to endemic). The traditional light flickering when the factory next door starts up sort of thing perhaps needs only a modest voltage drop to be noticeable - I guess a drop from 240V to 220V would be very noticeable - so how often would it drop to below 207V? If there were deliberate 1976-style voltage reductions across the country in an attempt to reduce demand, load-shedding a few extra EVs might even been seen as beneficial rather than a problem.

   - Andy.