Lighting systems to save energy in educational classrooms

Abstract

In educational buildings a significant component of the energy used is spent in illuminating the interior of the building. As the energy costs rise, increasing effort has gone into minimizing the energy consumption of lighting installations. This effort could follow three basic directions: new more efficient equipment (lamps, control gear, etc.), utilization of improved lighting design practices (localised task lighting systems), improvements in lighting control systems to avoid energy waste for unoccupied and daylight hours. By controlling the lighting in such a way that the lighting level is always accurately matched to the actual need allows to save on the energy costs and to improve the human comfort and efficiency. Establishing an integrated lighting control concept is a very important part of the lighting design process. The paper describes two different smart control systems designed according the same concept but with different components, for the lighting systems in two classrooms at the Engineering Faculty of the Universty of Rome Sapienza. The installations are realized according to a research project about the assessment of the impact of lighting control systems in electrical energy consumption and energy commitments. The results are useful to compare the two different control approaches (switching and dimming) and the two different kind of actions (with or without luminaries upgrade) in order to analyze costs, energy consumption and comfort. The two different control technologies are compared with respect to a third classroom without smart control, used as reference for evaluations.