Especially the heater. If your gas motor is tiny and not running all the time, how does the cab interior heat? If it’s electric, wouldn’t that destroy your gas mileage?
yes, all of those things affect the ultimate range of the vehicle; it’s just a matter of total energy. Somehow, the car has got to find or make up for the energy used by those devices. In a hybrid, all the energy eventually comes from the gasoline in the tank. A 13 gallon gas tank holds 470 kWh (kilowatt hours) of energy. A pure electric holds between 24 and 60 kWh in its batteries (I don’t know what the Tesla stores, it must be higher than my figures). Anyhow, against these energy stores, an electric heater will take 1500 watts; run it for an hour and you’ve removed 1.5 kWh from the car’s total energy store. But compare the 1.5k against hybrid and pure electric. You can see who’s thinking they might drive with the heater off. I’ve not measured the current draw of the lights (on my 24 kWh electric truck).