For construction consortium Levvel (BAM, Van Oord, Rebel) Vocare Ledlight supplied amber-colored solar LED lighting, so-called "Bat lamps", for the work sites along the Afsluitdijk so that it does not disturb the bats living in the area. Bats are greatly troubled by blue and ultraviolet light because it makes it difficult for them to navigate with their sonar. Using amber light significantly reduces these problems. With amber - orange - light, we take into account the Human-Bat Response Ratio. The light color is then insensitive to bat eyes, but the light is sufficient for humans to still perceive properly.