A model study of the daylight and energy performance of rooms adjoining an atrium well

Daylight has been regarded as a significant environmental advantage of atrium buildings because the natural light can illuminate potentially dark core areas and decrease energy consumption. This study has investigated the average daylight factors (overcast sky conditions) and annual lighting energy load (real weather conditions of Sheffield, UK) in adjoining spaces to assess the fundamental daylight performance and energy performance in an atrium model. Radiance and Daysim (based on Radiance algorithm) were the tools to simulate the daylighting and lighting energy use. A comparison of the measurement and simulation showed the validation of the basic Radiance simulation in the model. In terms of the well façades (decided by the ratio of window area to solid wall area) and well surface reflectance, the variations of daylight level and annual electrical lighting use in the adjoining rooms have been analysed and some design strategies for supporting preliminary design decisions are presented. Only the square atrium model and relatively simple climate conditions have been considered in the investigation.