Converting existing streetlights to LEDs saves cities money and electricity

For years, the orange glows of high-pressured sodium (HPS) streetlights have been a nearly ubiquitous nighttime sight. Recently however, cities have begun replacing them with light emitting diode (LED) streetlights’ whiter, crisper radiances. The numbers illuminate why. A General Electric comparison of its streetlight products shows that a 100-watt HPS light initially yields 55 lumens per watt, while a 95-watt LED light initially produces 74. LEDs have better color rendering and greater longevity, too— whereas an HPS light has a life of 24,000+ hours of life, LEDs last 50,000+ hours.