The overwhelming consensus from the LED lighting industry is that retrofit linear LEDs—specifically T8s—are a grand misstep; a blight upon an otherwise promising technology.

But are replacement linear tubes getting a fair shake? After all, history tells us that many emerging technologies—now widely adopted—suffered early setbacks and failed to gain initial consumer confidence and industry support.  Could this be the same trajectory the retrofit linear LED tube is on?

source: LED SA

1. Safety and liability concerns

The European Commission Low Voltage Directive Administrative Co-operation Working Group (LVD ADCO) expressed their concerns over retrofit LED tube safety in a 2011 Recommendation report, especially in terms of electric shock. This mainly applies to the linear LED tubes with integrated drivers. This type of LED tube is most widely used, as it is considered easier to retrofit than those with external drivers. However, this is also where safety (and compliance) issues arise.

Why are LED T8 tubes susceptible to electric shock more than non-linear LED bulb? The installer must modify the fixture by bypassing or removing the existing ballast so that the LED can run directly off the line voltage (a fluorescent tube uses the ballast).

• If the fixture includes a starter and magnetic ballast, the installer must modify the existing control gear by removing/opening the starter and removing/shorting the magnetic ballasts.

• If the fixture includes an electronic ballast, the installer must bypass the electronic ballast completely and wire the power directly to the end socket of the tube.

Concerns:

• UL safety rating becomes invalid when the ballast is removed or bypassed
• Documentation may not be read and safety issues may ensue
• Maintenance worker unknowingly replaces a previously retrofitted LED tube with a T8 fluorescent when the socket is running directly off the line voltage
• A retrofitting company upgrades a facility to T8 LED and are liable if a maintenance worker performs an unknowingly unsafe operation

2. Unrefined technology

Below are some of the technical issues that retrofit LED linear tube critics often cite:

• High heat: In an integrated LED tube, all electronics are housed within. As a result of the restrictive space inside the tube, excess heat is generated with nowhere to go. The high temperatures reduce the performance of the components.
• Poor lifetime of LED driver: For all electronic components to fit inside the confines of the LED tube, smaller (and therefore inferior) components are used. In addition, the high temperatures reduce the lifespan.
• Inadequate controlled dimming support/inferior dimming: Many retrofit LED tubes are non-dimmable or require phase-cut dimming. It is also difficult to find adequate controlled dimming support.
• Inferior lumen output: Department of Energy (DoE) CALiPER testing reports indicate that LED T8 replacements do not provide a similar level of lumen output when compared to their fluorescent counterparts. Lumen depreciation is also a problem.
• Inferior CRI: The CRI for LED tubes is rarely over 80.
• Poor CCT retention: Even the newest models are illustrating color shift problems at 9000 hours. It has been reported that the CCT, when measured, is not the same as specified by the manufacturer and that there are irregularities in the nanometer range of 400-700 nm (Dennis McCarthy, SSL Product Specialist).

3. Uncompetitive pricing

While LED tube prices are coming down, they are still more expensive than fluorescent tubes (~$25-$70 for LEDs vs. ~$3 for fluorescent). In addition, integrated LED tubes cannot be installed without modifications to the existing fixture, which, based on the requirements, can be significant. From a straight financial perspective, critics of integrated LED tubes say the return-on-investment (ROI) cannot be justified.

Unlike non-linear LED bulbs, many utility companies do not offer rebates for LED T8 replacements, even those with Design Lights Consortium (DLC) listing.

There’s no doubt LED tubes are improving–higher efficiency and better volume pricing should be available in the next 6 to 12 months–but now may not be the time to jump in. Calculate you ROI and when it looks like it’s down to 18 months to 2 years, consider making the investment.

Remember, every electrical product has safety risks and warnings. Technology is constantly advancing with new research and new ideas. Costs decrease with improved manufacturing and product design.