A Review of the Evolution of Daylighting Applications and Systems Over Time for Green Buildings

Abstract

The continuous increase in the world's population and the fact that humans spend most of their day in indoor environments has increased the demand for energy. The rational consumption of electricity, especially lighting and its provision in buildings using various strategies, has become an important topic on the minds of many researchers and developers. In recent years, with the increasing the awareness of sustainable development due to economic and social conditions, daylight is seen as an effective way to save the energy, reduce significant pressures on existing energy infrastructure and reduce the environmental impact. The use of daylight in buildings by different sunlight applications/systems, whether traditional or innovative, is more than just an alternative or supplement to electric lighting, as it has many benefits in terms of economic, environmental, and health. Traditional applications are divided into three strategies: general, improving, and developing. The interior spaces of multi-story buildings (i.e., taller and deeper) are often not illuminated by natural light during the daytime, due to the distance from these spaces to the nearest traditional general application through which daylight must enter. Innovative Daylighting Systems (IDS) or remote source systems have been developed to transmit daylight into the building core (i.e., inaccessible places or rooms) and windowless areas or parts so they can be called Structure Core Daylighting Systems (SCDS). Eighteen SCDS/IDS were reviewed and discussed in the form of a comparison between them in terms of their components, historical progress, installation locations, and a brief description. The study focused on the systems that had already been commercialized or at least produced a large-scale prototype that had been installed in a real structure over the past five decades. Although SCDS/IDS are technically powerful enough to provide illumination for remote spaces, there are some important shortcomings that have hampered or prevented their widespread use, such as the extremely high-cost, efficiency for some of them, utilization difficulties, and application limitations. In addition, the equilibrium between the cost of their components and their performance efficiency is one of the great fundamental decisions that an engineer designing for these systems must make. Finally, the paper presents the latest design approaches that have been developed to overcome their identified shortcomings.