In certain applications, LED systems are tremendous success stories, achieving energy savings and lowered maintenance costs as promised. Based upon anecdotal evidence and DOE testing, LEDs perform best when mated to drivers that are designed for the LED lamp.
As an example of the fast-paced rate of improvement in LED technology, a CALiPER report from January 2009 found that SSL street lamps did not meet or exceed the performance exhibited by traditional florescent lamps. But that has changed, according to the October 2010 report.
"[CALiPER] has found decent results with some downlights, streetlights, decorative and cove lighting fixtures," says Audin.
There are many success stories for LEDs in outdoor and accent lighting applications. There are a bevy of reasons why LEDs are so well suited for those environments:
"The really big thing, especially for outdoor use, is reduced maintenance costs," says Audin. "Two-thirds or more of the savings are based upon maintenance, not energy savings. That's a big difference in how we think about them."
For accent lighting, because LEDs emit directional light and little to no heat from the lamp itself, they could easily be a preferred choice for gallery use above artwork and other items that require illuminated highlights.
Because energy to light office space can account for up to 40 percent of a building's total energy costs, it's only logical that facility managers might want to replace overhead office lighting with LED lamps. But it's still worth the facility manager's time to take a close look at specific applications.
For one thing, facility managers should ensure that LED retrofit devices — replacements for screw-in compact fluorescent as well as T8 and T12 lamps — function as well as fluorescents. "If you're saving energy by putting in LED lamps but are only getting half the light output, then it doesn't work," says Chip Israel, of Lighting Design Alliance and board officer for the Illuminating Engineering Society.
LED Performance Improving
Where to Use LEDs
Factors for LED Retrofit
Specifying LED Systems