T5: Bringing Greener Lighting Options to the Warehouse/Manufacturing Sector

T5%20fluorescent%20lights.jpgMuch has been made about the use, abuse, and benefits of CFL lights. But almost entirely about their consumer level use. What about on a company level? What about all the warehouses, industrial and manufacturing facilities out there, needing high bay (ceiling) lighting? Unless well daylighted they require some sort of illumination, all day, making up 30-60% of energy costs. What options are out there?
One that came across my desk yesterday was T5. If you look up next time you’re in a warehouse store, the lighting you’ll likely see is some variation of metal halide, those glaring circular lights, which use 250, 400, 1000, even more watts. Clearly, there’s room to improve.

T5 are what’s called High Output Linear Fluorescent lamps. They, in comparison, use 54 watts of power, and when clustered in a 4 lamp fixture, it’s still a total of 231 watts, vs. the typical 400 watts for a metal halide light. On the T5 site, it says, “In most cases, maintained foot candle readings are almost always better per energy dollars spent.” and has a chart comparing lumens (illumination) per watt, T5 near the top. My question is, how does that translate when the number of watts is far less than metal halide fixtures?
Other advantages of T5 fluorescent lights:
T5 are also apparently graceful agers. They lose only 5-6% of their output over time, as compared to up to 35% on metal halides, which use the same amount of electricity to produce less light over time.
They are quick to light, whereas metal halides need time to warm up. Along with the waste in energy, this precludes them from being used with motion sensors, etc, which would further reduce energy consumption, since they wouldn’t need to be left on the entire time they might need to be used.
They’re easy on the eyes – literally. Their Color Rendition Index or how accurately they light things in comparison to natural light, is 85-98%, as compared to 65-93% for halides. For you lighting pros out there, they also maintain color output throughout their lifetime and can come in various color temperatures as well.
That said, one question remains, which I could not find the answer on the T5 site. What are they made of? Do they, like CFLs, contain mercury? If so, how much, and how can it be safely disposed of? Still, at a savings of as much as 2 tons of CO2 annually per lighting fixture, their positive impact is clear.
Readers: What lighting options are you using in your business now? What options are coming up that we should know about? Please comment, below.
Paul Smith is a sustainable business innovator, the founder of GreenSmith Consulting, and has an MBA in Sustainable Management from Presidio School of Management in San Francisco. His overarching talent is “bottom lining” complex ideas, in a way that is understandable and accessible to a variety of audiences, internal and external to a company.

Paul Smith is a sustainable business innovator, the founder of GreenSmith Consulting, and has an MBA in Sustainable Management from Presidio Graduate School in San Francisco. He creates interest in, conversations about, and business for green (and greening) companies, via social media marketing. || ==> For more, see GreenSmithConsulting.com

7 responses

  1. Paul,

    T5 and T5H0 based fixtures are certainly growing in popularity for lighting warehouses, manufacturing facilities and any other application with high ceilings, but there’s a long way to go. Most building owners don’t realize they could significantly improve their bottom line just by switching out the lights in their warehouses. These fixtures use 50% less energy than the standard metal halide high bays. When you realize that on average, 40% of electric consumption is on lighting, these fixtures can reduce the bill by 20% or more. For a typical warehouse, that can be $30,000 or more.

    To sweeten the deal, many utility companies and state agencies provide significant cash rebates to customers that undergo a lighting retrofit project. This is done as a way of managing demand in states with limited generation capability. These rebates coupled with $0.60 per square foot tax deductions made available through the Energy Policy Act of 2005 make lighting retrofit projects one of the fastest paying projects that a facility can undertake.

    At Relight with T5, we’re passionate about helping to reduce our impact on the environment. I appreciate the mention and I hope it helps get the word out throughout the industry.

  2. Here goes…

    The power consumption of a 4-lamp T5 is indeed far less than a conventional 400W metal halide. The metal halide consumes 400W for the lamp and another 50 or so for the ballast for a total of 450W. The T5HO fixtures consume 54W per lamp plus another ~17W for the ballast for a total of 233W. That’s almost 50% less power for the T5HO fixture. The important thing is what those two fixtures do with the power they consume. The lumen output of the standard metal halide lamps starts to decay very sharply as soon as it’s put into service, but the lamp continues to draw the full 450W of power until the day it finally fails. The T5HO lamps not only decay much more slowly (due to lower mercury content), but also put out much better quality light. The human eye is an amazing thing. Even if the absolute quantity of light on a surface may be a tad bit higher, the fact that the the light is more natural makes the eyes adjust much better to it.

    T5 and T5HO lamps are made using rare earth phosphors that improve color rendition and lamp performance. As for the mercury question, they do contain minor amounts of mercury. TCLP compliant T5HO lamps can have as little as 1.4mg of mercury per lamp for a total of 5.6mg for a 4-lamp luminary. Metal Halide, by contrast, contains upwards of 60 to 70mg. For comparison, the mercury content in standard T12 lamps can be as high as 30mg per lamp! TCLP is a test designed to simulate what happens to a product if it is disposed of in a landfill. The government sets limits for the amount of mercury that can leach out of the product in that condition. All major manufacturers product T5 lamps that pass this test. There are also a number of ways to recycle these lamps without sending them to a landfill.

    Hope that helps.

  3. Paul, thanks for writing about high efficiency lighting in commercial properties. One important note about funding: performance contracting makes it possible for companies and other organizations to finance lighting upgrades without committing capital dollars. The improvements pay for themselves with the cost savings they generate in lower utility bills.

    1. @Scott: I know it’s been a long time since you asked the question, but since I happen to revisit this comment, I thought it was worthwhile answering…

      A change from T12 to T5 does indeed require different ballasts. Older fixtures can be retrofitted to accept the slightly shorter T5HO lamps by making use of a T12 retrofit kit. These kits include a new ballast, new lamp holders, lamps and sometimes new reflector systems.

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