Performance assessment of an active sunlight redirection system in areas with different climate: A comparison

Abstract

The aim of this work is to assess the impacts, both in terms of daylight efficiency and energy impacts, of an advanced daylighting system that utilizes a heliostatic configuration for sunlight redirection in a deep South oriented office room in two (2) different climate conditions. Conventional daylighting systems such as windows, and clerestories placed on building facades, for a variety of reasons, have been proven ineffective in solving the problem of deep interior daylighting. This effect even with the use of modern daylighting techniques can effectively maintain the required illuminances. In such cases, systems that are designed to take advantage both the direct and diffuse natural light while maintaining and improving occupant visual comfort, particularly at greater distances from the external walls can provide higher work-plane illuminance levels deeper into the space. The results summarized here demonstrate that, if selected according to daylight climate and integrated appropriately with electric lighting controls, the system can enhance daylight in building interiors and thereby promote energy savings. It should be noted, however, that the performance of these systems is dependent on daylight availability. Nonetheless, the information presented in this paper demonstrates the potential benefits and shortcomings from the use of sunlighting technologies in different climate zones.