How do streetlamps work?

Question

Is it programmed to turn on when they can't sense UV or is there a guy pushing a button to make it work? I am assuming it is different depending on where you live.

Answer 1

The lamp uses a photosensor to detect light and turns on when the amount of light is small.  Powered by city electricity lines.

Answer 2

Street lights are not solar powered.  They are powered by the city utility lines, and each street light has a night sensor that detects daylight, turning the light on when it is dark and off at sunrise.  These just sense visible light, not UV.

Answer 3

they build up power from the sun during the day is programmed to turn on when they can't sense any light