by Wout van Bommel, Van Bommel Lighting Consultant

Lighting professionals normally working with electrical light need to have more knowledge of daylight behavior and its influence on the comfort and wellbeing of office and factory workers. Intelligent systems that link daylight with electricl light are already a long time available. They can contribute considerably to energy efficiency and have a positive influence on the final effect of lighting in a building. Design of these systems can only be done with a satisfying result by professionals with a detailed knowledge of both daylight and electric light.

For electric lighting professionals, this becomes even more important because of futuristic developments in windows. Complete transparent OLED windows are principally possible so that we can have daylight and artificial light from one single source. Small sized prototypes have been produced already some years ago. Studies are being carried out to develop transparent solar windows of normal  flat glass. The glass gets a low cost luminescent coating which captures  radiation of non-visible wavelengths over the whole area of the window. That captured radiation is redirected efficiently to the small edge areas of the window where it is captured by solar cells attached to the edges. These solar cells can subsequently be used as power source for the electric lighting that is linked to the daylight system. Also here prototypes have been shown. Another interesting futuristic possibility to use  daylight in buildings is translucent concrete. Glass fibers are being mixed with the concrete substance. This type of concrete may be used for example for subway stations and other underground buildings. Also here knowledge will be required about how daylight entering a building in this way combines with electric lighting.


Wout van Bommel

Van Bommel Lighting Consultant

past president CIE