It's spring here in Seattle, and that means warmer temperatures. With that, I've noticed substantially improved energy efficiency in my Roadster. On my drive in to work this morning (temp about 60F, about a 50/50 mixture of freeway and surface streets), I used just under one ideal mile per mile driven. During the winter when it was typically 25-30 degrees cooler, this never happened. I don't remember the exact numbers, but I think it was something like 20% worse (1.2 ideal miles/mile driven), and it may well have depended on how cold it was. I generally considered the ideal miles range to be a joke, and often saw 280-300 Wh/mile. I've heard lots of stories about how Li-ion batteries don't hold as much charge when they're cold. However, that's not the car is reporting. It's saying that the battery capacity is about the same, but that the rest of the car is using more energy. I don't think that running the heat is sufficient to explain the difference (though it's a pretty big drain). So, either the car really is using more energy when it's cold for some reason that I don't understand, or else the VDS is reporting lower battery capacity as higher energy use. Have other people had this experience? Does anyone have an explanation?