Creative Commons

This dissertation examines the role of lighting in commercial buildings, by investigating the impact of natural and artificial lighting on the indoor environmental quality. The relationship between daylighting potential and energy savings in the commercial sector is explored, since commercial buildings are big lighting energy consumers and the exploitation of natural lighting could contribute to energy use efficiency. Previous studies have shown that daylighting systems reduce remarkably the energy use, while the combination of systems has even more beneficial effects. This study has two goals: 1) to present prior researches’ results and existing technologies linked to energy savings due to daylight exploitation and 2) to suggest different shadings’ design proposals for an existing office space and evaluate the energy loads and indoor conditions. The broad research in literature concerning experimental approaches, case studies and grounded theory formed the base for the research strategy. A thorough assessment of the indoor environmental quality conditions in an existing office space has been conducted, including measurements and simulation. Having employed modeling and simulation software, two shadings’ configurations were tested to illustrate the various effects on energy use. The findings from the research showed that even with quite easy to apply methods, it is feasible to achieve energy use reduction and better comfort conditions. The results address a controversial belief among practitioners that horizontal louvers are the optimum solution for southern façades. Single lightshelf integration with the curtain wall could offer higher energy savings. The findings of the study are dependable on the space’s characteristics and the electric lighting’s equipment. A re-thinking of the role of lighting in commercial buildings is prompted, offering insights into existing building stock’s refurbishment, including the configuration of shadings that aim at the reduction of energy loads. It has been learnt that the assessment of indoor environmental quality is influenced by multiple factors and the control of only optical comfort, even though it could minimize the lighting energy consumption, it could simultaneously burden the rest of the comfort conditions.