Experimental investigations are carried out to obtain more information about the heat and especially the mass transfer phenomena concerning evaporation of water from a prototype evaporation surface for low consumption and electric motor vehicles. One prototype evaporator with various structured surface coverings of different materials is tested. The basic test section consists of an industrial prototype evaporator with fine longitudinal re-entrant grooves. The test conditions of the air temperature and the air humidity vary between 20 °C and 40 °C and 20 % and 40 % respectively. The heat fluxes range from 430 W/m2 to 1175 W/m2. Water is used as working fluid. Results of the prototype evaporator and three different structures of different material properties, covering the surface of the prototype, are presented in this paper. First results show a good heat transfer from the evaporation surface to the air flow above the surface.