The justification for upgrading a lighting system frequently centers on reducing energy consumption, but there are additional benefits associated with improved light quality and output. Better lighting allows employees to work faster with fewer errors, in turn reducing the frequency and costs of downtime. Good lighting and less eyestrain make visual inspections and inventory counts easier. Lighting enhances building security and reduces accidents on the job and in the parking lot, reducing absenteeism and insurance rates.
The National Lighting Bureau, a nonprofit lighting information source, refers to this as high-benefit lighting. High-benefit lighting considers the requirements of the people, spaces and tasks involved to achieve lighting objectives while also delivering energy and maintenance savings.
Fluorescent lighting manufacturers are improving their technology continuously to provide these benefits. Consequently, more operating companies are choosing fluorescent systems for replacement and retrofit projects.
Advantages of fluorescents
Fluorescent lighting was less practical in the past because the lamp life was shorter and the lumen maintenance was relatively low. In high-bay facilities, these are serious concerns because of the cost and inconvenience of replacing burned out lamps. Buzzing, flickering and poor color rendering index also were disconcerting. Modern fluorescent T5 and T8 systems have overcome these issues and are gaining in popularity, especially as an alternative to older high-intensity discharge (HID) lamps in high-bay applications.
In comparison to HID, fluorescent lamps now offer significantly longer life, better lumen maintenance, improved color rendering and enhanced output. They provide greater control of light distribution and offer higher light uniformity. Additionally, they can reduce lighting energy costs by 50% or more versus a 400W metal halide system. Improved electronic ballasts provide quicker starts and retain lamp life longer.
“We have seen a significant shift from HID systems to fluorescent systems in the plant and warehouse environment,” says Ronald Paduchak, linear fluorescent product manager, GE Consumer & Industrial. “Not only do fluorescents save energy and reduce environmental impacts by taking power off the grid, but they can provide better light and quality, too.”
“Based on energy savings alone, a typical fluorescent retrofit pays for itself in less than two years,” says Otto Hottendorf, senior manager of linear products, TCP. “For a two-shift operation on either coast, payback can be within a year.”
T5 lamps are a big growth area throughout the lighting industry, particularly in facilities with high ceilings. GE Consumer & Industrial’s TCLP-compliant T5 linear fluorescent lamps now offer a rated life of 30,000 hours. The company’s T5 covRguard series includes 54W high output lamps for indirect and up-lighting high-bay applications, and new 28W high-efficiency lamps for general lighting applications.
T8 lamps also are being used as industrial lighting system replacements. TCP’s high-lumen SuperT8 lamp for the company’s high-bay lighting system provides 10% more light than standard T8 lamps. The SuperT8 starts at 3,100 lumens and has a rated life of 24,000 hours.
The ActiViva “feel good” lamp range by Philips provides high quality lighting and is designed to have a direct effect on the way people feel, making them more alert, awake and energized.
With HID systems, a fairly large area is put into darkness if a one-bulb lamp goes out. If that bulb is on a 40-foot ceiling, lamp replacement can be a slow process. Fluorescent fixtures generally have multiple lamps. If one lamp goes out, the others still function, and maintenance can be scheduled rather than reactive.
Fluorescents are better suited to occupancy sensors and automated light controls than HID systems. “A two-shift facility with lighting controls can reduce the operating time on their fixtures by thousands of hours per year,” says Hottendorf.
Because frequent starting with instant-start ballasts can shorten the lamp life, GE developed the UltraStart Program Start ballast for T5 and T8 fluorescent lamps used in frequently switched applications. The new ballast provides for an average of more than 150,000 starts.
“High-efficiency ballasts operate at 90% or higher efficiency and consume less than 10% of the total system power, compared to the 15% to 16% consumed in the past,” says Jeffrey Plaskon, ballast product manager, GE Consumer & Industrial. Their UltraStart and Instant Start ballasts both operate at high efficiency.
E-mail Contributing Editor Sheila Kennedy, managing director of Additive Communications, at [email protected].