Demonstration of Recessed Downlight Technologies: Power and Illumination Assessment

Technical Report · Fri Nov 20 04:00:00 EST 2009

DOI:https://doi.org/10.2172/971108· OSTI ID:971108

Parker, Steven A; Beeson, Tracy A

Solid state lighting (SSL), specifically light-emitting diodes (LED), has been advancing at a rapid pace, and there are presently multiple products available that serve as direct replacements for traditional luminaires. In this demonstration, conventional recessed lights in a conference room were used to compare conventional incandescent A-lamps, incandescent reflector R-lamps, dimming compact fluorescent lamps (CFL), to an LED replacement product. The primary focus during the study was on light delivered to the task plane as provided by the power required by the lighting system. Vertical illuminance, dimming range, and color shift are also important indicators of lighting quality and are discussed in the report. The results clearly showed that LEDs, with dimming-capable drivers, are much more efficient than incandescent and CFLs. Further, LEDs provide much smoother and consistent dimming than dimmable CFLs. On the potential negative side, it is important that the dimming switch be identified as compatible with the LED driver. A wide variety of dimmer switches are capable of dimming LEDs down to 15% of full light output, while select others can be capable of dimming LEDs down to 5%. In addition, LEDs can be intensive light sources, which can result in uncomfortable glare in some applications and to some occupants. Higher ceiling (9-foot or greater) or non-specular reflectors can act to alleviate the potential for glare.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 971108
• Report Number(s): PNNL-18860; EL1703010
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
COLOR
FLUORESCENT LAMPS
ILLUMINANCE
LIGHT SOURCES
LIGHTING SYSTEMS
OCCUPANTS
SWITCHES