For thousands of years, natural lighting affects human beings and consists one of the most important factors in building design. The benefits of the sun forthe human body are numerous and undeniable. In the field of architecture, the goal is to bring daylight into the core of the building while controlling it. The use of natural lighting instead of the artificial one has a positive impact not only on physical and mental human health but also on energy saving. The amount of the daily required energy is reduced and thus the environmental conditions are improved.
Nowadays, the daylightsystems that find application are numerous and each one has different characteristics and is used for different reasons. In this research work, after making a reference and a small description of them, we analyze the passive tubular daylight systems, or by trade name, the light pipe. A historical overview describes how light pipes got their present form andit is mentioned a list of the commercial systems that are used today. Gathering all the necessary information on light pipes such as installation modes, improvement techniques, etc. some practical applications are set forth.
Finally,it was made an experimental study in order to compare the light pipes with roof openings. By using the Energy Plus program at specific rooms, there have been calculated different geometries of light pipes, measuring their performance. By placing roof openings of the same size as the light pipes, we made the final comparison of performance between them, as far as the levels of illumination and their variation during the day is concerned.