Plus, I'm given to understand (from a friend who bought a new BMW plug-in hybrid last year) the battery range reduces by a third if all the accessories required for winter driving are switched on, so I imagine the same situation would apply to an EV ?
Or to put it another way, if a car with 75kWh battery uses 25kWh to run lights and heater
Does a car with a 150kWh battery use 50kWh to run lights and heater?
Or a car with 300kWh battery use 100kWh?
No reason why it should.