Scientists realize for several years that global light pollution greatly increases. Long-term measurements of the sky brightness at different observatories show that the night sky annually brightens by about six percent. In a few decades, the night landscapes on Earth have thus changed enormously. The night is so many places become the day. This has great impact on many organisms, including us humans.
Light pollution has become a problem, as in many areas are greatly illuminated in urban areas. Large cities are particularly affected by this problem, since many objects are lit in public spaces like streets, squares and landmarks Sunsets to sunrise. Here misaligned lights often used. Much of the nocturnal light pollution caused by unnecessary scattered light due to inefficient beams. The city of Zurich, for example, will in future use light more efficiently and says the light pollution with the use of LED technology in street lighting to the fight.
Since mid-November 2014 partially new, intelligent LED luminaires are tested in Zurich. They are equipped with a motion-dependent control, a technology of Norway, which operates on the basis of radar. In principle, the lights slumber in standby mode, which reduces power by half. Once approaching cars, cyclists and pedestrians, they turn in seconds to 70 or 100 percent power. In addition, objects of public space are accurately displayed, so that the light is only there really is where it is needed. This gives a total energy savings of 83 percent and a significant reduction of light emissions and costs.