Are these types of bulbs like the ones you use in your house?
You’ve probably noticed that compared to the light bulbs in your house, the light bulbs in streetlights seem to burn out a lot less often. But why is that? Let us explain!
It turns out that bulbs found in streetlights aren’t like the bulbs in our regular table lamps or light fixtures at all. They are high intensity discharge, or HID bulbs, which are much brighter and last much longer than regular light bulbs. HID bulbs don’t have the same structure as normal household light bulbs—instead of a filaments which burn out at the end of their short lives, HID bulbs contain a gas that conducts electricity. Since there’s no finicky filament to decide when the bulb’s life is over, streetlights last much, much longer than traditional incandescent light bulbs.
Though LED traffic signals are becoming the norm these days, you’ll still find some old-style HID light bulbs in streetlamps and traffic signs around the country.
