This is a misconception. Heat pumps can improve things a little but often far from as much as people expect. The problem is that in cold conditions most of the

This is a misconception. Heat pumps can improve things a little but often far from as much as people expect. The problem is that in cold conditions most of the loss is from reduced battery performance right from the start. In really cold conditions it can be 50% and more reduction in battery performance. This is energy you're not getting back, heat pump or not. In addition the performance depends on the temperature. There is a sweet spot and the colder it gets from there the less effective it becomes. At around -20 degrees C and below it's effectively useless. There are already vehicles that have been tested in real world conditions. Tesla Model 3s exist with and without heat pump. The difference isn't that large, around 10% more range with the pump in perfect conditions. I've seen people doing tests sleeping in their cars all night and in cold North American winters it's not pretty. With a fully charged battery you will get enough heat for a comfy good nights sleep, 8 hours or so. So lets say in an emergency situation you can stretch it to 12 or so by reducing the temperature. But that's on a full charge! Most cars getting stuck in traffic are not going to have fully charged batteries. It absolutely is a problem with EVs even more than with ICE cars.