Active daylight harvesting technologies that are currently available in the market have often suffered from wide-spread market acceptability due to their high cost and imperfect performance. Passive systems, though simple and affordable, typically cannot harvest higher potentials of daylight, which is dynamic over days, months, and seasons, due to their static nature. There is a research and market gap that calls for investigation towards the development of low-tech, manually adjustable, high-performance daylighting mechanisms to be used as an alternative to active daylighting solutions, which are often controlled by building automation systems. This research proposes a framework to support the development of daylight harvesting mechanisms, which will allow for low-tech yet temporary adjustable systems, merging some of the advantages of active systems with passive ones. The hybrid of the above two categories will be a manually adjustable light harvesting device that will allow for quick adjustment through mechanical means to few predefined positions. These positions will be customized to each location to achieve optimum daylight harvesting. The resulting device will allow for flexible adjustment to daily and seasonal variations of the sun's path, while retaining a level of simplicity and elegance towards low-cost installation and operation. Significant effort was made in the initial phase of this research to use experimental studies as the primary method of investigation. However, given the nature of daylight and practical constraints in the field, the experimental method was found to be not productive enough for extent of this research. As a result, simulation studies were ultimately used to generate the necessary data for the development of this framework. For the simulation phase 'DIVA4Rhino,' a climate-based daylighting software and 'Grasshopper,' a graphical programming tool for Rhino, was used to first construct a parametric simulation loop. Next, a reduced set of parameters for a manually adjustable light shelf system were tested for daylight performance, as a 'proof of concept'. Finally, based on the previous two steps, a framework to help the development of manually adjustable light shelf systems has been defined. This research shows that light shelves, even when kept fixed at a single optimum configuration for the whole year, can increase interior daylight performance in most locations and orientations. It also shows that indoor daylight harvesting can be further enhanced if the light shelf is manually adjusted on a seasonal basis. Amongst the variations tested, rotational adjustability has been found to contribute most to the increase in performance. Segmented adjustability, e.g. where the inner and outer sections of a light shelf are manipulated separately, was found to extend performance of light shelves even further though not by significant amounts. / Ph. D.

Public buildings are considered to be the most power consuming buildings in the world. To reduce power consumption earlier studies propose greater use of natural daylight to illuminate surroundings, hallways and areas where to preform common work tasks and where artificial lighting is only used for the actual work space and places where higher light levels are required. In office buildings with available daylight, it has been shown that people have a greater general well-being, improved health, reduced absenteeism and increased productivity. The purpose of this study is to investigate how different room configurations can increase the amount of daylight in offices. The essay is based on an experimental study in the form of a questionnaire in which participants have evaluated and documented their perceptions of the visual properties regarding daylight. The evaluation has been carried out with scale models of different room configurations, but with the same window size and window positions. The results show that a room configuration with embrasures provides the most effective daylight harvesting. Embrasures contribute with maximum visibility, brightness and provide maximum light scattering. Room configurations with rounded corners have proven to give the most even light ratio between the light and dark areas of a room where the light is also spread most evenly along the walls. According to an evaluation of the visual properties of daylight, a room with rounded corners is perceived to be the most comfortable room and provide the softest and gentlest light impression. The study is limited to evaluate the amount of daylight and the visual properties of daylight in large office spaces designed based on energy-efficient passive houses with thick facade walls. / Offentliga byggnader räknas som de byggnader som har störst energianvändning i världen. För att sänka energianvändningen föreslås ökad användning av dagsljus för att lysa upp omgivning, korridorer och platser för allmänna arbetsuppgifter och där den artificiella belysningen endast används vid arbetsytor och platser där högre ljusnivå krävs. I kontorsbyggnader med tillgängligt dagsljusinsläpp har det också visats att människor har ett ökat allmänt välbefinnande, bättre hälsa, minskad frånvaro och ökad produktivitet. Syftet med studien är att undersöka hur olika rumsutformningar kan bidra till ökat tillvaratagande av dagsljus i kontorslokaler. Undersökningen bygger på en experimentell studie i form av en enkätundersökning där testpersoner har utvärderat och dokumenterat sina uppfattningar kring dagsljusets visuella egenskaper. Utvärderingen har genomförts i skalmodeller med olika rumsutformningar men samma fönstermått och fönsterplacering. Resultaten har visat att rumsutformningar med fönstersmygar ger det mest effektiva dagsljusinsläppet i en kontorslokal. Smygar bidrar med högst synbarhet, ljushet och uppfattas ge mest ljusspridning. Rumsutformningar med rundade hörn har enligt dagsljusmätningar visat ge jämnast ljusförhållande mellan de ljusa och mörka delarna av ett rum där ljuset också sprids jämnast efter väggarna. Enligt en utvärdering av dagsljusets visuella egenskaper anses ett rum med runda hörn mest behaglig att vistas i samt ger det mjukaste och mildaste ljusintrycket. Undersökningen är avgränsad till att utvärdera dagsljusmängd och dagsljusets visuella egenskaper i stora kontorslokaler utformade enligt krav för energieffektiva passivhus med djupa fasadväggar.