CBEA High-Efficiency Troffer Lighting Specifications
Fifty percent of all commercial fluorescent lighting fixtures are recessed troffers in 1'x4', 2'x2' and 2'x4' configurations, in operation for more than 10 hours a day on average and collectively consuming more than 87 terawatt-hours (TWh) of electricity annually.
In 2011, a CBEA Project Team working to support the market introduction of high-efficiency troffers developed a specification that allowed for high-efficiency LED and fluorescent technologies, and addressed the 2'x2' category of troffer products. On February 15, 2012, Version 3.0 of the specification was released, expanding the specification to address 1'x4' and 2'x4' product configurations. Potential savings from applying the specification range from 15-45% on a one-for-one basis and up to 75% with the use of controls. If all commercial troffers were upgraded today according to the specification, we could save 26 TWh of electricity annually.
CBEA members can benefit from this project in many ways, from being better informed on the potential of high-efficiency lighting troffers (from DOE research and reports from other members), to being among the first to hear about new and promising technologies, to participating in demonstration projects and purchasing products that meet the specification requirements.
The following table shows the benefits of high-efficiency lighting troffers, as defined in the CBEA specification.
|Efficacy||Less wattage is required to produce equivalent light levels.|
|Controls||Inherently dimmable but compatibility should be verified prior to commitment.||Dimmable when mated with dimming ballasts and associated controls.|
|Environmental Impact||Contains no mercury.||Contains a very limited amount of mercury (less than the amount allowed in fish). Some lead in glass.|
|Longer Life/Lumen Maintenance||Expected long life of 50,000+ hours, but actual end-of-life performance depends on numerous factors.||Expected life of 24,000 to 52,000 hours. Actual value depends on ballast plus lamp pairing and controls.|
The following table highlights the performance parameters of the specification for the troffers.
|Minimum Initial Luminaire Light Output (lumens)||
|Differing initial values are due to the high lumen maintenance of fluorescent lamps.|
|Minimum Luminaire Efficacy (lm/W)||
|Measured according to IES LM-79-2008 (LED) or LM-41-1998 (Fluorescent)|
|Minimum Lumen Maintenance/Rated Lamp Life||For LED-based Luminaires
L70 ≥ 50,000 hours
For Fluorescent-based Luminaires
Rated Lamp Life ≥ 30,000 hours
|For LED-based Luminaires
Based upon-L70 based upon IES LM-80-2008, In-situ Temperature Measurement Test (ISTMT) and IES TM-21-2011.
For Fluorescent-based Luminaires
Rated lamp life based upon rapid-start ballasts with 12-hour operating cycles.
|Spacing Criteria (SC)||
|Spacing Criteria is the ratio of luminaire spacing to mounting height and establishes the point at which uniform illumination occurs between fixtures at a given mounting height.|
|Correlated Color Temperature (CCT)||2700K
4500K (LED Only)
|Nominal CCTs and tolerances as defined by:
For LED-based Luminaires - ANSI/NEMA/ANSLG C78.377-2008 "Specifications for the Chromaticity of Solid State Lighting Products"
For Fluorescent-based Luminaires - ANSI/NEMA/ANSLG C78.376-2001 "Specifications for the Chromaticity of Fluorescent Lamps."
Chromaticity tolerances defined by ANSI C78.376 correspond to a 4-step MacAdam ellipse and ANSI C78.377 corresponds to a to 7-step MacAdam ellipse (approximated in the case of C78.377). In addition to the nominal CCTs defined for fluorescent sources, SSL products add a 4500K nominal CCT.
|Minimum Color Rendering Index (CRI)||Ra ≥ 80 and R9 > 0||Equivalent to "800" series fluorescent lamps.|