Glare analysis of an integral daylighting and lighting control strategy for offices

Abstract

Complex Fenestration Systems (CFSs) can significantly impact both the visual and non-visual daylight effects on the occupants as well as the energy performance of buildings. To ensure that those impacts improve the overall situation, proper control algorithms are required if the CFS can be operated. The state of the CFS directly and immediately effects the indoor lighting situation. The thermal condition of the building is usually strongly but not directly influenced by the condition of the façade system due to thermal capacities. In this study an experimental integral control strategy, called Integrated Lighting Module (ILM) is investigated in terms of it's glare prevention capabilities and compared to a cut-off- and a simple rule based control logic. The ILM is an autonomous software package capable to run on building management hardware to control façade systems and artificial lighting in real buildings in an energetically optimised way. The adaptive sampling algorithm raytraverse is employed to calculate Daylight Glare Probability (DGP) values, which are used as a benchmark for the control strategy comparison. The other aspect of this comparison is the opening of the façade, which is evaluated as statistics how often each possible façade state is selected by each control strategy.