In many municipalities and cities are to be exchanged for new ones in the course of energy saving o

LED Street Lighting - loss of the night and the quality of life
"And then, one always has to repeat the truth, because even the error around us is preached over and over again, not of individuals, but from the crowd. In newspapers and encyclopedias, in schools and universities throughout the mistake is on top, and if it is comfortable and pleasant, in the sense of the majority, which is on his side. "J. Wolfgang von Goethe
In many municipalities and cities are to be exchanged for new ones in the course of energy saving old street lamps. The desire for energy conservation and also the possibility to receive grants from the state, makes this issue to date. This raises the question whether the conversion costs with the actual energy savings to be achieved in a meaningful relationship to each other, led expo especially when the primary energy cost for producing new bulbs, and so involving. And the new light is also adapted to the chronobiological rhythm of humans and animals?
Light of modern LED lamps is very blauhaltig usually what is perceived by most people in the evening as unpleasant. Blue light is biologically highly active led expo and affects the production of hormones (melatonin), which is particularly relevant in the evening, since it can interfere with sleep significantly. Natural daylight in the evening is very red Altig at sunset and is low on blue. Incandescent or halogen light the way, is very similar. All modern light sources, LEDs radiate very particular with extremely led expo a lot of blue. A cost-effective lighting can usually only by light with a lot of short-wavelength (blue) light and produce the least possible long-wavelength (red and infrared) light. This investment is actually included? Is paid for so in any case with a change of the street scene by a lighter and especially blauhaltigere lighting in contrast to the orange-yellow light color of the sodium led expo lamps, which is generally perceived as very pleasant and always emits a hormone neutral light! The cost of replacing the lamp: 50,000 euros. Energy savings per year: 13,306 KW / h or 3,500 euros. Interestingly, most of the now renewed lamps had been installed only in the year 2006. There is an interesting contribution in Merkur online. Total time 371 lamps were replaced. "The one-time investment 30000-40000 euro'm an annual savings of around EUR 16 000 on utility bills over". http://www.merkur-online.de/lokales/weilheim/weilheim/stromausfall-ganz-weilheim-ohne-strom-3653528.html
The light from LED lights is biologically very active. The specific wavelengths of LED light in the range 430-460 nanometers, are located in the blue region. Light in this wavelength range is biologically active and slows the release of melatonin, a hormone that controls the day-night rhythm led expo in the body. The light emissions of such LED lights überbmittelt us humans, the information that it was day, which is of course in the evening usually not desired and is perceived by many as unpleasant.
Now one might think that the concern over high blue content in the LED light is an exaggeration, because after all if it were at the new bulbs yes to "Warmtonlampen". The listed bulbs color temperature in Kelvin (eg light bulb 2700 Kelvin) has a correlated color temperature which is determined only on three measuring points led expo in the spectrum. Although there are bulbs that have a nominally similar color temperature such as incandescent lamps, so the spectral composition is still completely different, without that we could see with our eyes. Although "warm tone" LED, for example, have a lower proportion of blue but it is still many times higher than, for example, in a incandescent lighting. Hard to believe, led expo but true! There is a simple, but only the few people known explanation. This is key to understanding the information presented in this post!
Color temperature calculation method found an interesting information about sodium vapor lamps efficient sodium led expo vapor lamp sodium lamps have an extremely high light output and even an ecological aspect: insects are hardly attracted by this light! http://de.wikipedia.org/wiki/Natriumdampflampe
CONCLUSION: For the sake of well-being and health, and not least because of a beautiful cityscape in the night, it would be desirable if a not too bright and one of our natural rhythm matched light would be used as lighting in the city. Cool white and so-called warm white LED bulbs do not meet those criteria!
Most people do not feel in the evenings woh