According to different studies and experts, around 40% of the energy consumed globally is buildings’ related. Artificial lighting consumes a significant part of all electrical energy consumed. In offices from 20 to 50 percent of total energy consumed is due to lighting. And most importantly, for some buildings over 90 percent of lighting energy consumed can be an unnecessary expense through over-illumination.
Looking at the figures above it seems clear that in today’s world there are plenty of commercial buildings (the majority of them by far) in which lighting is not automatically controlled at all, in other words, someone switches on and off lights at the start and at the end of the day. Other more sophisticated buildings (few of them) implement some sort of automatic control of lighting making this switching on and off by automatic control based on presence detection, or calendar/hourly basis. And other even more sophisticated ones (very few of them all) implement really effective lighting control providing just the appropriate light level in any part of the building at anytime, having in consideration many variables like daylight coming from outside, presence of people in each area, the required light level according to workplaces, etc.
It is obvious that the more effective control we apply to lights in a building the more comfortable we’ll make it for people who spend a good part of their lives there, and of course the more energy efficient we’ll make the building itself, with all the benefits related to it: reduction in electricity bill, reduction of maintenance budget, reduction of carbon footprint, etc.