The short version
Real-world efficiency varies more than any spec sheet suggests. Cold weather, highway speed, and headwinds are the big levers. Expect 250-290 Wh/mi in mixed driving for most Long Range configs; winter highway driving can push past 350 Wh/mi.
What moves the number
- Speed: 75 mph uses noticeably more than 65 mph. Aero drag grows with the square of speed.
- Temperature: cold air, battery heating, and cabin heat all draw energy. Precondition while plugged in.
- Heating: seat heaters + steering wheel heat beat the cabin heater for efficiency.
- Tires: pressure below spec increases consumption; check monthly.
Reading the range meter
The displayed range is an estimate based on the EPA rating and recent driving. Use the energy app in the car for a consumption-based projection — that is the number to trust for planning.