Fuel consumption with roof tent | Soft shell VS Hard shell

We test the difference in fuel consumption between soft-shell roof tents & hard-shell roof tents.

In the test, a Volvo v70 from 2004 is driven over a distance of 85km at 100km / h.

The section is driven on the motorway back and forth.
With soft shell, hard shell and without roof tent completely.

You see the result in the movie!