Lighting Energy Savings in an Office Environment Simulating a Motion Detection Dimming System

Abstract: Shortages of electricity in larger cities in Sweden are becoming more common and might increase with an increased consumption. The thesis focuses on lights due to approximately 19 - 20% of the total electricity consumption coming from lights. It examines whether a control system consisting of an Motion Detection Dimming (MDD) System combined with a Daylight-Linked Control System (DLCS) that illuminates the workspace of individual employees while avoiding bright spots in a Swedish office context achieves an energy gain. An MDD system activates different lamps depending on if motion was detected while the DLCS adjusts the brightness the lights emit depending on the natural light in the area. Data was gathered which connected spans of cloudiness to lux (lx) values. This allowed for simulations for the year with the least amount of brightness and the year with the most amount of brightness, since the 2000s. Workers movement in an office environment was also documented. The results for both of the data gatherings where imported in to a simulation that calculated the electrical energy, in kWh. Three scenarios were created and simulated; all workers being at the office moving around, hybrid working and lastly all employees being present but never leaving their desks. The results showed that an energy gain could be achieved from all three scenarios, 48,9 - 50,1% for the first, 40,1 - 41,2% for the second and 4,4 - 5,5% for the final, compared to the offices current consumption. According to the results an MDD-system would lower the energy consumption, in a Swedish office environment, without creating a ”bright spot”. This meant that the master thesis succeeded in proving that it was, with high probability, possible. However, the savings would not increase significantly with the Daylight-Linked Control System.