I think the efficiency impact is important over the highway. There’s a pretty big drag difference. Drag being about half of the force needed for the engine to o

I think the efficiency impact is important over the highway. There’s a pretty big drag difference. Drag being about half of the force needed for the engine to overcome at highways speeds in the US. Especially if you’re already making efforts to reduce rolling resistance, drag can make a significant impact on the range of electric Semis (plus of course the operating costs and time to recharge and cost and lifetime of the battery). These things are easy to overlook if you’re just using diesel, but they matter a lot for electric. A cab-over semi might have a combined drag coefficient of over 0.7, whereas the Tesla Semi is around 0.35. So the 500 mile range of the Tesla Semi may be just 375 miles if using a conventional European cab-over design. That reduces the life of the battery as well, increases the proportion of the time spent charging, the cost per mile to charge, etc. And it can’t just be compensated with a bigger battery, either, because the vehicle is already near or at the weight limit. Drag actually matters.