Cities across the country are swapping the light bulb for a new type of light that saves energy and money. They're called LED lights.
"You're actually running it through a circuit board to provide light. With a traditional bulb you're just providing light to a filament to make it glow," says city traffic engineer Stephen Ernst.
Intersections in Rockford are equipped with LED lights. They're more expensive than a traditional $1.75 light bulb. LEDs cost between $80 and $120, but the lifespan is considerably longer. LED lights last about seven years.
The conventional light bulb has to be changed every summer and the operational costs for LEDs are much less expensive.
"I've seen studies show power consumption a half to a third of what it is for a conventional bulb," says Ernst.
You'd think the city of Rockford would benefit from the energy savings of LED lights.
"It would if we were paying for energy, but because of our franchise with Exelon we get traffic signal energy for free," says Ernst.
So although money savings isn't the driving issue behind LED use in Rockford, they're certainly helping cut down on power consumption, and the brighter light they emit helps drivers stay safe on the roads.
Ernst says every new intersection built in the city will use LED traffic signals.