Five-Year LED Torture Test

The light-emitting diode (LED) appears on track to become the light of our lives. Switching completely to LED lighting systems over 20 years could save the nation an estimated $250 billion and reduce electricity consumption for lighting by half, according to the U.S. Department of Energy (DOE).

But LED lamps cost more than incandescent or fluorescent models. To make that kind of investment, consumers need accurate information. For example: How long, exactly, are LEDs expected to operate before they fail? Manufacturers cite lifetimes in the range of five years. But no one had ever tested LEDs that long – until now. PML scientists are midway through a five-year torture test for 480 white-light LEDs from four different manufacturers. That work will provide authoritative answers.

Consumers also need to know if the color and intensity of the light from similarly-labeled lamps is the same. That’s why PML is helping the lighting industry by distributing “proficiency test kits” that can ensure that all lamps are tested and certified per strict standards.

"To date, we've worked with more than 90 laboratories, and we've gotten them to where they are within plus or minus 4 percent of each other,” says PML lighting scientist Cameron Miller. “By comparison, it took several years for labs to get within 7 percent for compact fluorescent lamps."