Electrical contractors are often on the front line when it comes to fielding lighting questions from building owners and facility managers. These inquiries tend to focus on the best ways to cut related energy costs. Today, that conversation almost always circles around to LEDs and options for moving existing fluorescent lighting to this highly efficient technology, including the choice of retrofit kits versus new fixtures. Figuring out the right solution for any given customer requires a knowledge of the benefits and shortfalls of each option.
Upgrading an older lighting system can be one of the easiest ways to cut a building’s energy bills. Lighting-related energy consumption has declined significantly over the last couple decades, dropping to 10% in 2012 from 17% in 2003, according to the U.S. Energy Information Administration’s latest figures. However, that leaves it tied with ventilation and cooling as a leading energy-expense contributor. Changing out lighting, whether with upgraded lamps, retrofit fixture kits or entirely new fixtures, is a much less expensive efficiency booster than diving into a facility’s heating, ventilating and air conditioning systems.
Swapping out existing fluorescent tubes for new tubular LEDs (TLEDs) appears to be an obvious upgrade. It might seem an easy, go-to response for facility managers that previously made similar transitions from older T-12 fluorescent products to more efficient T-8 systems.
However, ballast compatibility is a critical element in deciding which of the three types of TLEDs now on the market is appropriate for any given fixture. Also, the overall condition of existing fixtures needs to be considered, said Jill Mungovan, marketing leader for the contractor-focused TradeSelect collection, Hubbell Lighting, Greenville, S.C.
“Customers using LED tube lamps need to be cautious,” she said. “The installer should take extra consideration of the quality of the existing sockets for the lamps and whether additional fusing should be added to protect the user from future misapplied lamps.”
Simply switching to TLEDs also could lead to less-efficient lighting design because of inherent differences between LED and fluorescent lamp illumination patterns. This concern is raised by Eric Strandberg, senior lighting designer with Lighting Design Lab, a lighting-assistance outreach program sponsored by Seattle’s municipal utility, Seattle City Light.
“TLEDs, for the most part, are directional, not omnidirectional like fluorescent lamps,” he said. “That can work to advantage sometimes, but it doesn’t always. With some types of optics on fixtures, you actually decrease the efficiency.”
LED retrofit kits are a step up from lamp replacements. These products take advantage of existing fixture housings and power connections, but they often replace the majority of a fluorescent fixture’s interior workings. Such retrofit packages have been on the market for about a decade, said Jeff Hungarter, director of indoor lighting for Cree Lighting, Durham, N.C. Manufacturers initially targeted downlight fixtures because of the energy savings LEDs offered at that time versus incandescent lighting technologies.
“The payback, even at that time, was there because you were basically talking about taking a 65-watt BR30 and taking it down to the 20W range,” he said, quoting LED efficiencies available in the early 2010s.
The resulting two-year payback was an easy selling point for these mostly residential fixtures. Commercial troffers were a more challenging market, he said, because most owners already had upgraded to reduced wattage fluorescent lamps. Early-generation LEDs simply didn’t offer enough additional energy savings to make a new investment worthwhile.
“Six or seven years ago, you were in the 90 lumens per watt range—the story just wasn’t as strong,” Hungarter said, using the metric most commonly used to describe lighting efficacy. “Now, with LEDs up to 150 lumens per watt, it’s not even a question anymore.”
With these savings in mind, retrofit kits begin to make more sense than TLEDs, especially as costs for the kits have come down. Owners get better lighting because the kits offer features designed to maximize fixture performance. And, since many kits come with new reflectors or lenses, the fixtures themselves take on a refreshed look.
“Troffer kit designs are tailored for customer preference—do they want to keep their lens or parabolic louver or not?” Mungovan said. “Troffer kits give the customer more options, including lumen ranges, controls and battery packs. And, in most cases, they have a lower cost of ownership compared to replacing with just LED tube lamps. Using LED tube lamps also does not upgrade the look of the space, since it reuses the existing door or louver.”
Stay or go?
As owners begin to consider retrofit kits, they may find the cost of these products isn’t that much less than that of entirely new fixtures. The new-fixture market is benefiting from LEDs’ increased popularity—the vast majority of new lighting today is LED-based. So pricing is falling with the increased volume.
“From a cost perspective, when comparing a full LED troffer versus a troffer kit—they’re virtually at cost parity,” Hungarter said, noting the simplicity of the manufacturing process behind LED fixture production. “You’re just stamping out four pieces of metal.”
So, if today’s full fixtures are so closely priced to retrofit kits, why wouldn’t owners simply opt for something brand new? It turns out a range of economic issues beyond equipment costs can force a decision one way or the other.
“A lot of it has to do with local code—if you remove a certain percentage of fixtures, it can trigger a local code requirement for sensors or controls you might not have budgeted for,” Hungarter said. “And a lot of it also has to do with old buildings—they don’t want to go into the plenum.”
Strandberg echoed the role existing challenges—such as the possibility of obstructions or asbestos in plenum areas—can play in a decision for retrofits instead of new fixtures. But he also ticked off some of the drivers that could move the choice in the opposite direction.
“You might do a kit if you have issues with ceiling conditions, but you might want a new fixture if the basic components of the existing fixture are played out,” he said. “Also, if there are other renovation efforts going on, sometimes you want a new look or if you’re having to move fixtures around so much that the existing fixture isn’t appropriate.”
One issue electrical contractors probably don’t have to consider in weighing the options is the possibility of adding new controls. While earlier kits might have been limited in this regard, today’s products can be specified with many of the same sensors and control options common to new LED fixtures.
“The sensors are on-board and a lot of them are wireless, in case you didn’t have a network before—they’re being requested on a lot of projects,” Hungarter said, noting the quick uptake of new technology in the move away from fluorescent lighting. “LEDs are digital, so they’re a lot easier to control.”
Whichever option the customer chooses—retrofit kits or new fixtures—electrical contractors should consider suggesting field-testing any product up for specification.
“There are major manufacturers that have reliable in-house testing. If you’re dealing with one of those manufacturers and you understand the specification sheet, then it’s OK to go without testing,” Strandberg said. “But we’re still at the point where we’re seeing some marginal products coming onto the market.”
Mungovan said the importance of field-testing rises along with project size.
“It is always recommended that samples are ordered to evaluate the installation for large projects,” she said. “Electrical contractors should align themselves with a manufacturer willing to offer a time-based, risk-free trial program, so that they can install the fixture free of charge and see the results for themselves.”
With their similar costs and performance capabilities, retrofit kits and new fixtures offer the opportunity for lower energy costs compared to fluorescent luminaires in one-for-one replacement programs. But there also may be times when completely rethinking an existing lighting plan—rather than simply replicating it with updated technology—makes more sense. For example, today’s LED products can offer a higher light output than was possible with old-school fluorescents, so owners might be able to meet their lighting goals with fewer fixtures. However, planning is required to ensure such a move doesn’t create glare, shadowing or other lighting problems.
“If lowering the number of fixtures or lowering the lumen output is a part of the consideration, we highly recommend a lighting layout be part of the evaluation,” Mungovan said. “Recommended foot-candle levels need to be maintained for adequate lighting for the application. Lowering the fixture count in the space or lowering the lumen output will help maximize the energy savings, but it might come at a cost of lighting quality.
Rethinking an existing plan also offers the opportunity to take advantage of the design freedom today’s LED fixtures offer, according to Hungarter.
“The designs used to be very much squares and circles, troffers, and downlights,” he said. “Now you’re seeing a lot more linear lines of light mixed with accent lighting. And fixtures don’t always have to always be in the ceiling—organic LED technology can be embedded in walls or carpets.”
The new suspended linear fixtures that provide direct and indirect light also support the industrial look that has become popular in open office plans. Now, the dropped ceiling systems that help support traditional troffers can be eliminated, adding height and new volume to existing office spaces. Hungarter said it makes sense for owners to rethink lighting designs when undertaking such large-scale efforts to reimagine how workplaces function.
“We’re already making that investment in new spaces,” he said, while presenting an owner’s possible perspective. “We don’t want to spend all this money, and then leave the lighting in the same old two-by-two grid design we had before.”