I drove a similar route as the GP, 1100km round trip for a ski trip to Austria, aiming at 190kph.

I didn’t have to tank for the round trip, but I decided to tank on the way back cause in Austria tanking is much cheaper.

My car isn’t particularly new, but the lowest I’ve seen it use is 4.5l/100km and at 180-190 it uses 6.5l/100km.

In Germany most people don’t drive huge SUVs. Mine is a relatively sleek station wagon.

Reducing the aerodynamic surface of cars significantly improved fuel economy.