Available online 29 March 2013
Publication year: 2013
Source:Building and Environment
This study presents the results of a monitoring campaign aiming to further our understanding of occupants’ behavior regarding the manual control of electric lighting in combination with shading control. It was performed on eight single-occupied offices in the city of Porto, Portugal during periods ranging from 28 to 60 days per office, and involving minimal if any disturbance to the occupants regular activities. A wide range of environmental variables including workplane illuminance, window and background luminance, transmitted solar radiation and occupation state was measured with high frequency (20 min time steps or shorter), and a specific emphasis was placed on evaluating luminance distributions within the field of view. The study aimed to address a set of key research questions regarding typical illuminance ranges and occupancy patterns found in offices and their relationship to electric lighting or shading control actions. The main findings that emerged from this analysis were that electric lighting and shading control were influenced more by occupational dynamics (arrival and departure) than by the environmental conditions experienced over the day (daylight workplane illuminance or transmitted solar radiation) although with a large degree of variability between occupants and/or offices. It also revealed that while most of the behavioral models analyzed for comparison purposes were in qualitative agreement with field observations (e.g. more lighting switch-on actions at arrival for lower daylight illuminance), only one model (Pigg’s model) predicted the frequency of lighting switch-off events observed during the monitoring campaign with reasonable accuracy.
Publication year: 2013
Source:Building and Environment