| John J. Huebner is president of Mor-Lite, Inc., a company which specializes in designing and installing high-efficiency lighting in textile plants. His lighting designs and equipment operate in over 250 textile plants in the U.S., Mexico and several South American countries. He is a senior member of the Assn. of Energy Engineers and a Surveyor Ally of the U.S. Environmental Protection Agency.
Huebner is also a member of the Industrial Lighting Committee of the Illuminating Engineering Society. Establishment of lighting standards for North American Industrial plants starts with the deliberations of this committee.
Mor-Lite and Delta Woodside Industries recently shared an Award of Merit for lighting design from Energy User News, the first award of its kind ever given for textile plant lighting design.
In an exclusive interview, Huebner discussed textile plant lighting parameters with TEXTILE WORLD.
What are our choices for textile plant lighting?
For today's lighting, it boils down to two basic light sources fluorescent or high-intensity discharge (HID). Incandescent bulbs have been replaced by compact fluorescent. Mercury vapor is obsolete. Low-pressure sodium lamps never caught on in textile plants. I haven't seen much VHO fluorescent lately.
Which is best?
Both fluorescent and HID technologies have undergone dramatic improvement over the last 5-10 years. And each has advantages, depending on the application. For example, fluorescent lighting is ideal for linear production processes like spinning and weaving. HID may be best for dyehouses and some high-bay warehouse applications.
Which is more efficient?
On paper, the edge goes to HID lighting. That is, in terms measured purely by light output per unit of electrical power input. But fluorescent comes out ahead when measured in terms of actual usable light delivered where it is needed.
|What's new in terms of technological improvement?
A lot has changed. Lighting designers now use products that were not available as recently as five or 10 years ago. We have a lot more to work with. For example, old-style fluorescent lamps which would last only 12,000 hr and require frequent replacement now last as long as 24,000 hr and lose far less light output over time. This means you can design a lighting layout with fewer fixtures because the average light output per fixture stays higher, saving money.
Some HID lighting once had poor color-rendering properties, making everything look gray or yellow. That's pretty much a thing of the past if you select the newer high color-rendering HID fixtures.
What are some of the advantages and disadvantages of HID lighting?
Not in all cases, but in general terms, some advantages include:
Good energy efficiency.
Generally longer lamp life, sometimes exceeding 24,000 hr.
Easier maintenance, fewer bulbs to replace.
In the form of vapor-proof or sealed fixtures, they are often a good choice for areas with a high level of airborne contaminants.
Disposal/recycle cost is sometimes lower because of fewer lamps.
Glare is probably the biggest problem, because the light output comes from a highly concentrated source. This is compounded when fixtures are mounted at a lower location than that for which they were designed. Generally speaking, if your HID lighting is mounted higher than 18 ft above the floor, you are all right. I once visited a plant where the machine operators all wore baseball caps to cut down on the glare. That told me something.
Harsh shadowing when used over production processes.
Round distribution pattern may not apply well to linear production areas.
Possibility of inner-arc tube rupture for some HIDs.
Shutdown of 15 min/wk is sometimes required when light fixtures are operated on a 24-hr basis.
Lamps may require 10-20 min to relight if you have a power interruption.
What are some of the advantages and disadvantages of fluorescent lighting?
Again, in general terms, some advantages are:
A linear light source is often more efficient for linear production processes.
Glare and harsh shadowing are not usually a problem.
Addition of specular reflectors can dramatically improve system efficiency.
More lamps may mean more time for maintenance.
Not as good for high bay applications.
More lamps and ballast mean more disposal/re-cycle cost.
Open fixtures may not be suitable for areas of high airborne contamination.
What do you see coming?
In terms of new light sources, some breakthroughs may be coming, but most remind me of solar energy. It was promising, but cost is still an overwhelming obstacle. In the foreseeable future, look for further refinements of current technology. We've come a long way. The textile industry is now illuminating plants at less than half the cost of only a few years ago, with no sacrifice in lighting quality. While a lighting electrical load of 1.5-3 W/sq ft of floorspace was considered the norm a few years ago we are now designing lighting systems of less than 1 W/sq ft. For example, the award-winning Delta-Woodside Beattie Plant went from 1.71 W/sq ft down to 0.56 W/sq ft. And average light levels went up in all departments.
Any more overall observations or recommendations?
Yes. Many. But here are a few:
Don't skimp on lighting equipment quality. You will be sorry down the road.
Don't skimp on installation hardware. Misaligned fixtures have a way of making the whole plant look sloppy.
Low-bid type commercial fixtures have their place, but not in a modern, high-efficiency textile plant.
Take a hard look at all of your lighting options.
Money is to be saved if you do your homework.
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