The flip of a switch is one of the easiest tasks for a human being, and even that action often is unnecessary in today’s food production environment. Small wonder, then, that illumination often is taken for granted.
Light has multiple applications in food production. It’s an essential part of vision systems for product inspection, and the UV segment of the spectrum is effective at killing microbes and attracting pests. The primary use of lighting, of course, is enabling workers to see what they’re doing, and that necessity does not come cheap. Darigold, a Seattle-based dairy processor and a partner in the U.S. Dept. of Energy’s Better Plants Challenge, estimates that lighting accounts for 38 percent of its electricity use.
J.R. Simplot Co. is another Challenge partner. The potato processor is making its 420,000 sq. ft. Caldwell, Idaho, facility the center piece of energy-savings initiatives. Heat recovery from boiler stacks, fryers and other thermal sources accounts for most of Simplot’s efficiency efforts, but the firm also is focusing on lighting, including solar-powered LED for exterior applications beyond landscape accents.
That may sound like mood lighting for a suburban patio, but Simplot’s well-lit parking lots demonstrate the dramatic improvements occurring with LED light sources. After progressing from novelty to niche applications, LED is emerging as mainstream lighting for a broad spectrum of industrial applications.
Retrofitting a food facility to high-tech lighting isn’t on every company’s to-do list. Shat-R-Shield Inc., a pioneer in safety coatings for lamps, still provides incandescent bulbs and other old-school light sources. Hundreds of thousands of T12 lamps and fixtures remain in place in industry, even though they are going the way of the incandescent bulb.
But the economics of energy-efficient lighting are compelling, and rebate programs from utility companies make a strong case for LED over T5 and T8 fluorescents, points out Erin Noonan, Shat-R-Shield’s marketing director. “LEDs are taking over the world, but it’s going to be gradual,” she says. “Fluorescents are still selling left and right, but people are starting to adopt LED technology.”
Optimum light vs. good enough
Long life and energy efficiency are the hallmarks of LED, but the vibrancy and purity of the colors produced also is an important difference. In animal husbandry, LEDs that emit more red have been found to stimulate ovulation in laying hens and greater sperm production in boars, while those with more blue have a calming influence on some livestock.
Human perceptions and performance under a given mix of light and color is more complicated and varies by people’s age and environmental factors. The only illumination requirements come from the National Fire Protection Assn. and OSHA, which merely requires enough light to provide “a safe working environment,” according to Isaac Fedyniak, senior lighting engineer at Big Ass Solutions, the Lexington, Ky., firm best known for its large ceiling fans.
The ability to dial in a specific wavelength or color temperature is particularly important in automated inspection, and LED does it without cut-off filters, points out Jeremy Blankenship, architectural lighting designer at Larson Electronics in Kemp, Texas.
“LED fixtures have allowed machine vision systems to integrate a low-profile fixture that provides the exact wavelength needed for the inspection process,” he says. “Even for general illumination, such as high bay fixtures, there is a wide spectrum of fixtures on the market today that provide a wider range of color temperatures to mimic the daylight output of traditional lighting.”
General guidelines for industrial lighting are provided by the Illuminating Engineering Society of North America, but illumination is more of a balancing act than an exercise in human behavioral science. “Most companies defer to us for recommendations, says BAS’s Fedyniak. “We seek a medium between the best level possible and what they can afford.”
The calculation also must factor in possible impact on the food being produced. The silicone coating used by Shat-R-Shield blocks 99 percent of the UV rays emitted by the lamp, according to Noonan. That’s important to processors of meat, which tends to discolor over time, particularly when exposed to uncoated fluorescent lights.
If piecemeal replacement of existing lighting is done, Fedyniak suggests starting with refrigerated areas, then storage space. “LEDs love the cold,” he says, where they “tend to produce more light and can extend their life.” Occupancy sensors and dimmers further extend service life while lowering electricity consumption.
Hubbell Lighting Inc. introduced a series of sealed LED high bays for food processing last fall. Larson Electronics is emphasizing explosion-proof fixtures for grain processors and other food facilities where dust explosions are a potential danger.
While food candles, color temperature and uniformity are metrics for assessing artificial light, luminous intensity may be the best when contrasting LED with other technologies. For each watt of input, an incandescent bulb produces 10-12 lumens, half the output of halogen light (20-25 lumens per watt). Fluorescent bulbs generate 40-60. LEDs, on the other hand, are widening their advantage over other lights. Hubbell’s FPH series, for example, generates up to 113 lumens per watt.
Call it the irony of accounting, but food plant operators who want the superior brightness and lower operating cost of LED may be victims of their earlier lighting upgrades. Many firms upgraded to T5 and T8 fluorescents in the century’s first decade. Assuming a design life of 15 years, those systems are still being depreciated. Retrofitting to LED would mean writing off the undepreciated cost, a tax loss that accountants would rather avoid.
Owners or lessees of facilities with obsolete lighting, on the other hand, can claim a tax deduction of up to 60 cents per square foot if they can certify electric savings beyond an ASHRAE standard. The break, under section 179D of the tax code, was extended retroactively from the beginning of 2015 to the end of 2016 under the Tax Hikes Act of 2015.
Utility company rebates are another available subsidy. To help manufacturers navigate the rebate landscape, BAS began offering “rebate administration” last year, reports Ed Quinn, vice president of sales. “It’s not atom splitting, but it’s time consuming and arduous,” he says of the service.
Some rebate programs work against LED bulbs designed to work in an existing T8 fluorescent fixture. A North Carolina utility will underwrite half the cost of an LED high-bay but nothing for a LED bulb, Shat-R-Shield’s Noonan reports.
Rebates and tax issues aside, lighting technology is in transition, and unlike the options that came before, LED signals the merger of electronics and electroluminescence — the direct conversion of energy to light. Whether they convert now or later, food manufacturers are bound to see production in a new light.