A Meta-Analysis of Energy Savings from Lighting Controls in Commercial Buildings

Researchers have been quantifying energy savings from lighting controls in commercial buildings for more than 30 years. This study provides a meta-analysis of estimates of energy savings identified in the literature—240 savings estimates from 88 papers and case studies, categorized into daylighting strategies, occupancy strategies, personal tuning, and institutional tuning. Beginning with an overall average of savings estimates by control strategy, this paper adds successive analytical filters to identify potential biases introduced to the estimates by different analytical approaches. Based on the meta-analysis, the best estimates of average energy savings potential are 24% for occupancy, 28% for daylighting, 31% for personal tuning, 36% for institutional tuning, and 38% for multiple approaches. The results suggest that simulations significantly overestimate (by at least 10%) the average savings obtainable from daylighting in actual buildings.