This thesis develops a theoretic-experimental study dealing with the effects of an automatic shading device on the energetic performance of a dimmable lighting system and a cooling equipment. Some equations related to fenestration optical and thermal properties are rebuilt, while some others are created, under a theoretical approach. In order to collect field data, the energy demand-and other variables - was measured in two distinct stories, with the same fenestration features, of the Test Tower. New data was gathered after adding an automatic shading device to the window of one story. The comparison of the collected data allows the energetic performance evaluation of the shading device. (author) 136 refs., 55 figs., 6 tabs.