[ardecila]

Originally Posted by ThatDarnSacramentan

They might make streets safer, but they also make light pollution much worse.

From National Geographic:

In Chicago the adoption of LEDs will almost certainly reduce light pollution. The new luminaires are full cutoff, so they cast no direct light upwards unlike the old sodium vapor lights which had bulbous plastic diffusers and cast tons of light up into the sky (hence the crazy aerial photos).

The article is poorly written, it blames LEDs for increased light pollution when the increase is actually due to the expansion and growth of cities. In a case like the City of Chicago, the borders are fixed and we already have all the streetlights we're ever gonna have, so the switch to LED can only improve things.

Now, the different hue/frequency of light may have adverse effects on wildlife (or humans) within cities, but due to the full-cutoff designs, the new generation of LED lighting should prevent the spillover of city light into the surrounding rural or wild areas, and make those areas better for wildlife than they are now.