The performance evaluation of advanced daylighting systems in multi-story office buildings: measurement and simulation

This study investigates the climate-based performance of a lightshelf system in the context of multi-story office buildings, which is regarded as one of the most important strategies for achieving the comfortable daylit environment in areas with a highly luminous climate. Computer simulations by DAYSIM are performed to predict annual light quantities in the daylit zones. The DAYSIM results are also compared to several simplified experimental methods, in which the systems are tested under diffuse skies only. These methods use either Daylight Factor (DF) or Coefficient of Utilization (CU) as the performance indicator. The findings show that certain simplified experimental methods, especially the ones based on CU, can be reasonably accurate for climate-based assessments of sidelighting systems in a daylight climate similar to Raleigh, North Carolina.