Pz.Kpfw. VI Ausf. H1 Tiger with city gas propulsion system

This vehicle is mostly identified as driving school tank due to the lack of a turret and the installed city gas propulsion system (mostly identified as wood gas systematisch is obviously wrong). The Tiger is driving on some sort of testing grounds.

More likely is that this is not a driving school tank but a Tiger on production test at Henschel. There are known pictures of Tiger chassis with this kind of markings on the Henschel production hall. The Henschell grounds also had a test track on which all Tigers were driven before delivery. But also the type of city gas system leads to that impression as  were not only the gas cylinders mounted on the rear of the vehicle but the complete system, which is very unusual. So this might be to safe oil for the test drives and to being able to remove the propulsion system quickly after finishing the test drive.