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Best Practice Guide |
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Food and Beverage Growers and Processors |
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LightingHighbay and LowbayLighting and Energy Use Lighting can be a forgotten system. It has no perceived direct affect on production or profits, and lamps that have always worked, still work. Money invested in new conveyor belts or boilers, or in robotics and digital controls, on the other hand, has an obvious and measurable impact on operations. For this reason, even in the most state-of-the-art facilities, managers faced with competing choices tend to gravitate towards improvements in process equipment rather than building equipment. However, upgrading the lighting system is one of the best energy efficiency measures a facility can undertake in terms of payback, ease of implementation, energy savings, and secondary benefits. Lighting accounts for nearly 7 percent of total electricity use in industrial and manufacturing facilities, but accounts for almost 40 percent of electricity consumed by building (not process) equipment. Lighting upgrades can usually be done in-house and as part of routine maintenance, making these easy, non-disruptive, low-risk investments with relatively quick payback rates. As much as 50 percent of current utility costs related to lighting can be cut with energy-efficient lighting. A popular strategy is to adopt lighting projects as an initial energy project. The benefits are immediate and visibly tangible to employees and clients - lighting projects always improve people's ability to see clearly and generally make the indoor environment more attractive and appealing for occupants. Soon, you may find new people on-board with energy management as they "see" first hand the benefits. Best of all, cost savings can help finance (and justify) additional energy measures, and prove the bottom-line benefits of energy management. Industrial Lighting Systems Whenever evaluating any lighting project, consider ways in which overall lighting quality can be improved. Studies have suggested that improvements to lighting quality may boost worker productivity, improve plant safety, and reduce eyestrain and headaches. To quickly tell whether or not a lighting upgrade might make sense, ask these things:
A "yes" to any of these questions indicates that it may be cost-effective to upgrade your lighting system. Relamp, Retrofit or Redesign
Relamping is best suited when funding is limited and when switching out T12 fluorescents for T8s. Retrofitting focuses on the ballast as well as the lamp. Ballasts regulate electricity moving to the lamps. Magnetic ballasts typically used in older systems are being replaced by newer, more energy-efficient electronic ballasts (building codes and manufacturing standards are mandating the turn over of magnetic ballasts). Upgrading to an electronic ballast can result in savings of the same order of magnitude as upgrading from T12 lamps to T8s. Depending on the system to be replaced, redesigns can sometimes result in the quickest payback and the most energy savings. Delamping unneeded fixtures is one of the most important ways to reduce energy use. When new, better lamps and ballasts are installed, such as high-output T5 fluorescents with electronic ballasts, lighting quality is significantly improved - those old fixtures will not be missed! High-Intensity Discharge (HID) Lighting In most cases, HIDs can be cost-effectively replaced with high-output T5 (T5HO) fluorescents, even in high-bay applications. However, this entails a redesign of the entire lighting system, and usually cannot be done in-house. Fluorescent Lighting Fluorescents last longer than their metal halide counterparts and do not deteriorate as rapidly. A 400-watt pulse-start metal halide lamp, for example, loses approximately 33 percent of its initial lumens by the time 40 percent of its lamp life is over, compared to only 5 percent lost in either standard T8s or T5HOs. T12 fluorescent lighting systems have been common in lowbay facilities for some time, although they are often plagued by flickering, dim light and distracting humming. Upgrading to energy-efficient T8s or T5s can save up to 40 percent on lighting system energy costs. In highbay facilities where HID systems are common, T5HO lamps are a good choice. Because T12 lamps have much lower lumens per watt (LPW) and perform poorly compared with T8s and T5s, they should never be used to replace HID lamps. Additional cost savings are possible in refrigerated or climate controlled facilities because cooling loads are significantly reduced. Fluorescent fixtures and lamps generate much less heat than HIDs, which means that climate control equipment does not have to run as hard or as long to maintain correct temperature and humidity indoors. In some cases, businesses have been able to avoid costly heating, ventilation, and air conditioning upgrades by retrofitting their lighting system instead.
Ballasts should be matched to desired lighting controls. The availability of some features - like occupancy controls and dimmable lamps - depend on which ballast is used. Ballasts that provide these additional features have higher first costs, but achieve significantly greater cost savings through operations. Rapid-start ballasts work best with occupancy controls and extend the usable life of lamps. Occupancy controls, whether motion sensors or CO2 sensors, ensure that lights are on only where needed. This can reduce energy and costs by as much as 60 percent, and are an excellent choice in medium-use or low-use areas. Dimmable fluorescent lamps require dimmable ballasts. These controls work particularly well with daylighting and photosensors, allowing you to adjust the lighting system according to how much natural light is available. In California, where we enjoy abundant sunshine but high utility rates, dimmable systems coupled with daylighting apertures can achieve higher net savings over the life span of the luminaire. NOTE: HID fixtures can be matched to occupancy controls and dimmers, but are prohibitively expensive. Look up, look down, look all around What’s a Light?
Evaluating Light Quality and Energy Efficiency
Business ExamplesS. Martinelli & Company made four lighting upgrades in just one year, retrofitting highbay fixtures with T8 fluorescent lamps and electronic ballasts, and installed additional skylights that help minimize the need for electric light, and installing motion sensors that automatically turn-off lights in unoccupied areas like storage rooms, copy rooms, and hallways. Work was subsidized and assisted by programs from Ecology Action and PG&E.
J Wine retrofitted lighting in processing areas, replacing all 70 metal halide and 35 high pressure sodium high-intensity discharge (HID) fixtures with high output T8 fluorescent lamps and electronic ballasts mounted about 20 feet from the floor. This effectively reduced each fixture from 470 watts to 220 watts. Thanks to a rebate from PG&E, energy savings paid for the investment in lighting in 18 months.
Resources Energy Design Resources, Design Brief, Lighting Illuminating Engineering Society of North America, Discover Lighting. Walerczyk, Stan. Cutting Edge: Retrofitting, Relighting and Redesigning. Submitted July 26, 2003 for the World Energy Engineering Congress on November 12-14, 2004, Atlanta. DiLouie, Craig. High/Low-Bay Applications: Fluorescent or Metal Halide? Lighting Controls Association, November 2004. (accessed March 18, 2005). Northeast Energy Efficiency Partnerships, Design Light's Consortium. Know How: Highbay Industrial Lighting. Northeast Energy Efficiency Partnerships, Design Light's Consortium. Know How: Warehouse Skylighting. Wisconsin Public Services webpage Lighting: HID Versus Fluorescent for High-Bay Lighting. Includes comparison tables of color rendering and lumens per watt as well as an easy, online cost-effectiveness calculator. Northwest Food Processors Association Efficiency Practices website offers useful information and tips for the food processing industry. |