This is a question for people with engineering knowledge. The current Model S consumes about 280Wh/mile at highway speeds (let's forget city driving for the moment). The future Gen3 car will be cheaper and smaller, with a smaller battery, but still needs to maintain the same range (200 miles). I think a 50kWh battery may be a good starting point: 50,000Wh / 200 miles = 250Wh/mile Ways to extend range: -reducing size/weight by 20-25% -slowing the acceleration -using thinner tires -greatly reducing power used by the onboard computer systems etc. -eliminating side-mirrors -implementing rear wheel-covers as an option (I think they look REALLY cool, I don't understand what everyone's problem is) -using a more aerodynamic body shape (longer tail? like the VW XL1) So after doing all that, what is the absolute lowest Wh/mile figure possible at highway speeds (55mph) for a Tesla Gen3 BlueStar Model E? Or for ANY future 4-door car? Will it ever be possible to break 250Wh/mile (only about 10% less than 280Wh/mile)? If not, why not? Is aerodynamics the single most important factor? How much power do you save by (for example) cruising at 53mph instead of 55mph?