The Sales pitch:
“XYZ Lamp Company Direct Replacement LED lamps plug right in to existing ﬂuorescent T8 ﬁxtures, so there’s no need to replace your old instant-start ballasts.”
The fine print:
“DOE finding based on careful analysis and testing results from DOE’s CALiPER program, which has systematically benchmark-tested these products with the linear fluorescent lamps they’re designed to replace. The results of that testing have shown that LED T8s produce far less light than the fluorescents they’re intended to replace, out of proportion to the energy savings.”–Jim Brodrick, Department of Energy
Let’s take a closer look-
- Direct replacement: Plugs directly into existing ﬂuorescent T8 lamp ﬁxtures
How will they interact with existing fluorescent ballasts? The savings is strictly the bulb replacement and does not appear to include the ballast factor and wattage of the ballast. Does the new bulb have a dedicated LED driver to replace the existing ballast?
- Energy eﬃcient: Cuts energy usage by half compared to ﬂuorescents T8s
However, CALiPER testing reported fixture efficiency was higher with LEDs however, fluorescent fixtures had higher light output and higher overall efficacy for both lensed and parabolic louver troffers.
- Long lasting: 50,000 hour rated life reduces maintenance costs
What about end of life lumens? Fluorescent T8s have 92% lumen maintenance at end of life, compared with 70% lumen maintenance typically assumed for LEDs.
- Beautiful light: 110 degrees of clear, uniform, and ﬂicker-free illumination
Be sure to look at the CCT and CRI values. CALiPER reported “CCT values for most of the LED linear replacement lamps were similar to the fluorescent benchmarks (3200K to 4500K), but several of the LED lamps tested had atypical chromaticities that gave the light a greenish or purplish appearance. The CRI values of the LED products ranged from 63 to 76, with most of them approximating those of lower-quality fluorescent lamps.”