The city intends to replace all of its lights with LEDs, but even before it has completed that project, it has realized energy cost saving of more than 60 . The city’s lighting maintenance costs have also decreased dramatically. The city logged more than 70,000 annual street lighting repairs before the retrofitting project began. In four years, that number dropped to just over 46,000 repairs per year.
Los Angeles is not an outlier on the spectrum of cities that have pursued retrofitting to LED street lighting. Its cost savings, both in annual energy and in maintenance costs, are typical of other cities, and that experience is creating a groundswell of interest among cities that seek to modernize their infrastructures with technologies that will both save them money and increase their appeal to an urban populace that is interested in green and eco-friendly technologies.
The energy efficiency of LED street lighting systems is apparent with simple math calculations. Traditional incandescent lights convert much of the energy that is used to power them into heat. LED lights use less than 20% of the energy that is required for incandescent lights and generate up to 30% more light per watt of energy (i.e. “lumens”) input. These two factors combined lead to the type of energy cost savings that Los Angeles and other cities are realizing after LED street light conversions.
The advantages of led srteet lighting go well beyond efficiency and cost savings. LED street lights can be controlled with pinpoint accuracy and, unlike other newer lighting systems (including sodium and mercury-vapor lamps), LED street lights can be turned on and off instantaneously. This rapid on-off response allows integration of motion-sensitive control systems with LED street lights, for example, to quickly increase the brightness of LED street lights when pedestrians are present and to dim them when pedestrians are no longer around. LED lights can be linked to emergency response centers to create brightly-lit paths and directional lighting for first responders.
LED lights are available in multiple colors and lighting temperatures, which can be combined to create unusual and enticing ambient lighting in urban settings. When urban planners start to examine the possibilities that LED lights present, they can find themselves overwhelmed by the possibilities.
Those possibilities have also transformed the specifications that urban planners and engineers have traditionally used to define and fill their urban lighting needs. They can still consider lumens, which is the basic unit for traditional lighting applications, but LED lighting systems allow for consideration of color rendering and color temperature, uniformity, and lighting depreciation, all of which can be combined to create unique solutions for street lighting applications.