Performance of advanced daylighting systems for functional lighting in buildings at high latitudes

Daylighting design has always been an inseparable component of architectural design. With the sun as the primary source of light and heat, daylighting design has historically been a point around which the entire process of architectural design is based. Nowadays, daylighting in architecture is seen as a segmental design task, as building codes prefer its expression through numerical values. This new perspective makes daylighting design less inspiring from an aesthetical point of view and more trivial, as solutions tend to be oriented around simply fulfilling a minimum requirement. In the last two decades, there have happened many innovations in the present sustainability marked. Many new daylighting systems have been developed based on the idea of increasing the energy efficiency and reducing the carbon footprint of buildings by enabling more daylighting indoors. These systems have been floating in the market of building components for the last 20 years but have yet to come to the shelves as a standard solution. The reason for this is a lack of reliable information on the effectiveness and profitability of the systems as well as whether they are appreciated by humans. Therefore, the research in this thesis aimed to develop reliable evidence that daylight transport systems (DTSs) can improve the human visual experience, increase the daylight levels indoors, and, thus, save lighting energy. This study was divided into three research parts, where findings were reported through five scientific papers in addition to an overarching essay. The research within this PhD study resulted in a profound understanding of the daylight techniques and daylight transport systems that can be used in buildings in the Scandinavian microclimate. The experimentation work resulted with an understanding of the quantity and quality of light delivered through an advanced daylighting system, a horizontal light pipe (HLP). Further, the full-scale study provided several insights in terms of the photometry of daylight supplemented via a HLP in a full-scale experiment, integration with an artificial lighting system, and lighting control. The energy-saving potential for artificial lighting, recorded via this full-scale study, is an important factor for further Zero-Emission Building (ZEB) development. The last and probably most important finding was the positive human appraisal of the space daylit by a HLP in a full-operative building. This provides a very important knowledge foundation fo