Lighting system control techniques in commercial buildings: Current trends and future directions

Artificial lighting is one of the major electricity consumption in commercial buildings and consumed about 17% of the total electrical energy. Therefore, there is a great potential to reduce energy consumption by implementing intelligent lighting control systems, such as integration of sensor technologies (occupancy and light sensors), advanced architectures (wireless- and network-based architectures), and intelligent control techniques (artificial intelligent and optimization). Moreover, an intelligent control system is capable of enhancing the visual comfort of occupants, and reduce electricity consumption and greenhouse gas emission. The lighting control system can be broadly categorized into three main techniques: controller-, optimization-based control, and hybrid. This paper presents recent and significant state-of-the-art interior lighting system control techniques in commercial buildings. The review focuses on several key research, including sensing technologies, objective functions and constraints, techniques, tools, and energy performances. A survey trend analysis is presented graphically and the findings are discussed extensively. Based on the comprehensive review of lighting control techniques, it is found that the optimization-based control technique is widely used by 51% compared to other techniques as it has superior performance to achieve higher energy savings while satisfying visual comfort of occupants, and at the same time the technique solves multi-objective problems effectively. Moreover, future directions have been drawn based on the highlighted gaps toward intelligent and sustainable buildings.