Mustafa ŞAHİN, Yüksel OĞUZ, Muhammed Mustafa KELEK
Introduction:Lighting is defined by the International Commission on Illumination (CIE) as "applying light to ensure that the environment and objects are seen as they are." In terms of light source, there are two groups: natural lighting and artificial lighting. Natural lighting is the kind of lighting that is done by using spaces such as windows and doors in architectural buildings by using daylight. Natural lighting is the kind of lighting that is done with the help of spaces such as windows and doors in architectural structures using daylight. The purpose of benefiting from the daylight is playing an important role in the construction of buildings today. The most basic purpose of using daylight on the buildings is to create a comfortable and efficient working environment. As a result of the researches done, the use of natural lighting increases the performance and productivity of the employees. Daylighting is also important in terms of reducing the energy consumption as well as providing the psychological and physiological needs of the people. The main purposes of illuminating interior spaces with daylight are; the efficient use of daylight, the provision of uniform lighting, the control of the dazzle, the visual connection with the outside world, and the feeling of the difference of the external brightness level during the day. Neatlydesigned natural lighting ensures that the building's energy consumption is reduced while balancing the heating and cooling loads. At this point, the concept of daylight factor enters into effect. The ratio of the average brightness level in the working plane to the horizontal brightness level in daylight is defined as the daylight factor. Aim: This research was conducted to investigate the effects of daylighting factor and natural lighting in constructions.Scope:With the increase of office-based buildings and shopping centers, the use of artificial lighting in the day increased greatly. In lighting systems, there are two main objectives to achieve effective energy use. These are to reduce the installation cost of the artificial lighting system and to reduce the use of the artificial lighting system. In other words, planning is essential to achieve maximum benefit from daylight during the design phase. Natural lighting systems are called passive energy saving systems because they do not need any energy source. Wall windows or roof windows are often used to take in the sunlight to the interior, and their size and design have a great importance. Light shelves and light pipes started to take place in the area of taking benefit of daylight with these type of traditional methods. The use of these systems, which can be called modern techniques in the use of daylight in buildings, is becoming increasingly widespread. In order to design the most suitable natural lighting system depending on the variables such as the function of the building, geographical region, climatic conditions, orientation, it is necessary to consider the characteristics of these techniques and to evaluate different options during building design. This study includes the economic, psychological and physiological effects of the daylight spectrum concept in terms ofnatural lighting, which are related to the illumination of the building. Constraints: When lighting systems are being installed, it is of utmost importance to reduce the cost of installation by designing an energy-saving based design that is suitable for the purpose. If unsuitable planning is done, it can lead to more than enoughenergy consumption even if an accurate view can be provided.Method:Even though different systems have been developed to make use of daylight in deeper structures, daylighting is most easily done with windows. The daylight factor is of great importance when this is done. The lighting made by the window is an unstable illumination. Any lighting device can provide a stable light. In other words, the lighting of inner volume is dependent on the lightness of the sky. The daylight brightness level in a room is specified as the percentage of interior and exterior lightness. Artificial illumination is required if the outside horizontal lighting level falls below 3000 lux. With this information, daylight factor concept is studied and this concept is examined under the name of natural lighting. Findings:It has been resulted that no need for electric lighting throughout the day with natural lighting systems which are designed considering the daylight factor.In this way it has been observed that electrical energy is protected. With the protection of the energies, itisseen that acid rain, air pollution, and global warmingare caused by harmful wastes released to the environment increase. Results:Random designs during the construction phase should be avoided for designing natural lighting system and necessary calculations should be made to ensure transfer of light to the interior volumes at adequate level with appropriate methods. It will provided optimum results in terms of visual comfort and energy saving.

Anahtar Kelimeler: Natural Light, Daylight Factor, Economy, Ergonomics.