Functioning of the landscape was evaluated from the point of view of energy flow in the brown-coal mining area in the northern part of the Czech Republic. We assumed that the change of land use was also reflected in energy flows. Our attention was focused mainly on the proportion of incident solar energy that is changed to latent heat within the process of evapotranspiration. The area of interest included brown-coal opencast (14 km 2) and its close surroundings (53.1 km 2). The land use data were acquired by terrain mapping. An average value of evapotranspiration for growing season was assigned to each land use unit. These values were obtained from the literature. We also obtained surface temperature and surface wetness from Landsat TM satellite data for the whole area of interest. These data present a good evidence of incident radiation converted to sensible heat. Furthermore, we verified the relation between evapotranspiration and surface temperature, and between wetness index and evapotranspiration. These relationships appeared to be significant when tested by Kruskal-Wallis test. Thus it was possible to compare the estimated evapotranspiration for land use before the beginning of mining as well as for a proposal study in which inudation of the brown-coal opencast was taken into account after termination of mining activity. The presented results of the estimated evapotranspiration in the area of interest confirmed the hypothesis that changes of land use have a significant effect on the total average evapotranspiration as an important function of the landscape.