An investigation shows that light pollution from Vienna’s street lighting has been reduced by 75 percent – thanks to a successful collaboration between the city and science.
An investigation shows that light pollution from Vienna’s street lighting has been reduced by 75 percent – thanks to a successful collaboration between the city and science.
I read the whole thing, yet still don’t understand how they actually reduced the light pollution. LEDs shouldn’t inherently create less light pollution than light bulbs, halogen bulbs etc…
They also wrote that street lights only contributed 8% to overall light pollution. 8 to 2% might be significant in the statistical sense, but that’s a pretty small decrease for the overall light pollution. Though I still appreciate that they’re doing something, rather than going full steam in the wrong direction.
The old streetlights were often quite non-directional. So you’d have illuminated bushes or walls next to the street, which is unnecessary. The new lamps simply have better directionality, creating light only where needed.
Let me guess they chose the most cold white light possible, that makes a xenon lamp appear warm, instead of the comfortable sodium vapour ones…
No they did not, they went for a similar color for the car parts of the street and actually a warmer tone for the cycling and pedestrian parts. That btw also reduces light pollution, as the white ones are much brighter then redish tones.
The large dark sky reserve here in NZ uses 2000K LEDs for all street lighting.
I can’t find an article detailing the streetlights they use. Like you’ve noted, and the bollard pictured in that article, they’re designed to spill zero light above horizontal.