Choosing optimized system for energy efficient lighting control

The overall objective was to promote the use of energy-saving, stable and user-friendly systems for the control and regulation of lighting in offices, schools, institutions etc. A total of 20 manufacturers and suppliers of lighting equipment was invited to participate in the study. Out of these 10 companies participates in initial meetings and 8 answered the questionnaire distributed.

The project was carried out in SBi's Lighting Laboratory, where installation and performance tests of the selected systems in a clear manner could uncover the strengths and weaknesses of the systems in order to achieve optimal comfort and energy savings. Unfortunately, many of the problems that arise in practice, was also a barrier for installation and testing in the laboratory. Although the suppliers themselves should install and tune the systems, there were difficulties in getting many of the systems to function properly. The result was that only 3-4 of the systems could be installed satisfactorily with a functionality as desired. Therefore the last part of the project was focused on a more principled comparison of two control principles, namely, an open-loop system, which controls according to how much light that passes the window, and a closed-loop system , which controls according the illuminance on a horizontal surface (in practice, the luminance of the surface).