Daylight is composed of direct sunlight and atmospheric light (sun radiation dispersed by water and dust). It is the reference illumination source to which our eyes are naturally adapted, so that we nearly always find it more comfortable and attractive than artificial light.Daylight is a carbon neutral renewable source of energy and can replace up to 80 per cent of lighting energy consumption during daytime hours, while also improving the health, well-being and attentiveness of the building occupants.