A preliminary study of occupants’ use of manual lighting controls in private offices: A case study

• Published in: Energy and buildings 2018-01, Vol.159, p.572-586
• Main Authors: Gilani, Sara, O'Brien, William
• Format: Article
• Language: English
• Subjects: Automatic control; Buildings; Case studies; Computer simulation; Control systems; Energy consumption; In-situ monitoring; Lighting; Lighting control system; Manual control; Mathematical models; Occupant modelling; Offices; Private offices; Probabilistic model reliability; Probabilistic models; Reliability; Sample size; Vacancies
• ISSN: 0378-7788; 1872-6178
• DOI: 10.1016/j.enbuild.2017.11.055

[Display omitted] •The impact of light control systems on lighting energy use was evaluated.•Probabilistic models were developed from a monitoring campaign.•Data-driven models and a set of control systems were implemented in simulation.•The manual-on system reduced the lighting energy use by a factor of seven.•Study start date and duration affected the reliability of the models. While building engineers attempt to reduce energy use and provide occupants with comfortable spaces by automating building systems, poor implementation and neglecting occupants' preferences may cause the opposite effect. Monitoring occupants-building interactions provides valuable information in this regard. The main objective of this research is to examine the impact of the manual and automatic lighting control systems on the lighting energy use in private offices using experimental and simulation approaches. Probabilistic models for occupants’ presence and lighting use were developed based on the empirical data collected in 25 perimeter offices for 15 months. After simulating the developed models, simulation results indicate a reduction in the lighting electricity use by a factor of seven with the manual control system in comparison with the occupancy-on/vacancy-off controls. The ratio of the time when the lights were on to the occupied period was reduced by 62% based on the experimental observations and 90% based on the simulation results, using the manual-on/vacancy-off control system compared to the occupancy-on/vacancy-off control system.