ENERGY SMART
As the sluggish economy continues to put a crimp in top and bottom lines, food retailers need to make sure they're not wasting a nickel. So basic in-store expenditures like energy consumption -- the second-highest cost after labor -- have taken on an even greater significance.As a direct consequence, retailers are demanding that their in-store equipment be configured with an eye to cutting energy
June 30, 2003
Anthony Coia
As the sluggish economy continues to put a crimp in top and bottom lines, food retailers need to make sure they're not wasting a nickel. So basic in-store expenditures like energy consumption -- the second-highest cost after labor -- have taken on an even greater significance.
As a direct consequence, retailers are demanding that their in-store equipment be configured with an eye to cutting energy costs.
In this special report on store equipment, SN takes a look at new equipment -- from refrigerated display cases to lighting to air conditioning/heating -- designed to minimize energy consumption, while maintaining store appearance and operations.
Some retailers have targeted energy efficiency as a core competency. For example, for the past two years, Food Lion, Salisbury, N.C., has been recognized with an Energy Star Partner of the Year award from the U.S. Environmental Protection Agency (EPA) for its efforts in reducing energy consumption.
Boise, Idaho-based Albertsons has also been proactive on the energy front. In the first year of an energy management program launched in July 2001, the chain reduced annual energy consumption by 10%, or 480 million kilowatt-hours of electricity per year, according to Scott Moore, director of energy management and procurement.
But it's worth noting that good equipment alone is not enough. "Supermarkets must teach people how to save energy," said Gary Markowitz, president of Kilojolts Consulting Group, a Lexington, Mass.-based energy management consulting firm. "Best practices start with education and culture."
Refrigerated-Case Overhaul
By far, the largest energy cost for supermarkets comes from refrigeration systems, which average about 38% of total in-store energy consumption, according to some studies.
One new approach to managing this consumption is to focus on total cost of ownership, rather than just the cost of installation. "Early on, everyone was focused on 'first cost,' then energy, and then maintenance," said Shawn Kahler, product manager, display cases, Hill Phoenix, Conyers, Ga. "Now it is the total cost, and no one point is more important than another."
That makes sense, said Kahler, because when the emphasis is on initial cost, manufacturers focus on cheaper components. As a result, valves (and systems) don't run as efficiently.
Another approach to energy saving is to simply reduce the amount of space taken up by equipment. Some new display cases, for example, include more product facings and cubic inches in less floor space. In May, Hill Phoenix introduced a six-door reach-in freezer called the ORZ6 that allows a case to have 27-inch-deep display shelves, rather than the standard 22-inch version. "The six-door unit allows you to eliminate one complete unit and associated installation and maintenance costs in an average lineup, without sacrificing display space," said Kahler.
Another space saver comes from Hussmann, Bridgeton, Mo. Its model RLNI frozen-food display case, introduced about a year ago, offers reach-in glass doors that are back to back, facing two aisles but in a single piece of equipment instead of in two separate cases.
This single case saves 14 to 18 inches of floor space, said John Behr, Hussmann's vice president, R&D and advanced engineering. Overall, each of the RLNI models consumes 4% less energy than two units, and uses 9% less compressor horsepower, he said. Display-case doors are another area where energy can be saved. In May, Hussmann unveiled the Innovator II no-heat door, which eliminates condensation with a special glass coating -- rather than heater wires -- that removes heat from the glass, said Behr. Using this door, a retailer paying eight cents per kilowatt-hour for electricity could save $160 per door per year in operating costs, he said.
Kysor//Warren, Columbus, Ga., has also recently launched energy-enhanced refrigerated display cases. In the first phase of the introduction, meat, dairy and reach-in cases provide design advances in such areas as the air curtain and insulation that allow them to operate using 20% to 25% less energy, said Jim Knudsen, vice president of sales and marketing.
Among retailers, Albertsons uses Hill Phoenix, Hussmann and Tyler display cases, most of which are able to prevent condensation inside the cases without the use of glass heat, according to Moore.
Winn-Dixie, Jacksonville, Fla., is installing new display cases for its store remodels. "At our St. Cloud [Fla.] store, we use a combination of Kysor//Warren and Hussmann products, including the Hussmann Impact line," said Paul Watson, maintenance supervisor at Winn-Dixie's Orlando, Fla., division. "For fresh meat, the high-vacuum cases can run at a higher temperature. This takes time off the defrost cycle."
Vendors are also targeting compressor and coil technology for improvements. For example, Hussmann has introduced new coil technology in its five-deck dairy case, an open multi-deck vertical case called model D5LE . "This improves energy efficiency by 10% by raising the evaporator temperature, allowing the compressor to work more efficiently," said Behr.
Hill Phoenix has also unveiled energy-efficient evaporator coils for refrigerated cases that Kahler estimated can save from 12% to 17% on energy costs on its meat and dairy cases. In March, Copeland Refrigeration, a division of St. Louis-based Emerson Climate Technologies, introduced the Vapor Injected Scroll Compressor (ZFKV), designed especially for smaller distributed refrigeration systems, said Kurt Gobreski, Copeland's director of marketing. "These smaller systems are located closer to the display cases and can significantly reduce the amount of piping, refrigerant charge, and leaks in a store," he said. The scroll compressor, he added, is optimized for frozen-food applications, and with 40% more capacity, can improve energy efficiency by 20%.
The Lion's New Lighting
Lighting accounts for about 23% of energy expenses in the average supermarket, according to Markowitz of Kilojolts.
To address those costs, Food Lion is currently taking part in a lighting retrofit program, said Chuck Rohda, regional maintenance manager, distribution, at Food Lion.
One of Food Lion's changes involves replacing neon lighting with LED (light-emitting diode) lighting. "LED has a longer life -- from 60,000 to 100,000 hours," said Rohda. "And it provides good color rendition for signage." Mary Beth Gotti, manager of the GE Lighting Institute, Cleveland, said that supermarkets are using more LEDs instead of neon for sign lighting, particularly colored LEDs to highlight different departments.
GE, said Gotti, offers energy-saving opportunities for fluorescent, metal halide, and halogen lighting applications. "Metal halide is one type that enhances the appearance of merchandise and the ambience," she noted. GE has 400-watt and 320-watt ceramic metal halide in high bay fixtures. The 400-watt metal halide systems in particular have been "a workhorse" for higher-ceiling lighting systems, she said. Food Lion is currently installing 400-watt ceramic metal halide lamps at its distribution centers.
Other new installations at Food Lion include T5 fluorescent lights, a smaller profile lamp, and the newest in a series of GE products that include the T8 and T12. T5 is the main light used by Food Lion, while T8 units are compact fluorescents used on docks and fixtures, explained Rohda. Gotti said that newer T8 lamps and ballasts can reduce watts by 18%, and provide about the same light output.
Food Lion's re-lamping and re-fixturing will be completed this year. "Four projects are under construction, and four are in the proposal stage," said Rohda. Although energy efficiency has increased significantly, it is not the only goal, he noted, adding that other factors include the quality of light, working environment and safety. Best-practice systems will consist of lights that are closer to daylight.
Albertsons also employs a variety of GE lighting products, including Eco Wattmiser lamps and Ultra Ballasts. "Our new lighting systems use more efficient lamps and electronic ballasts," said Moore. "This reduces the energy required to light our stores. Also, because the new lamps and ballasts give off less heat inside the store, the air-conditioning load and thus the energy required to cool the store are reduced."
Cooling Off
In heating, ventilation and air conditioning (HVAC) systems, which account for at least 28% of supermarkets' energy usage on average, humidity is gaining more attention, said Lee Churchill, national sales manager at Seasons-4 Inc., Douglasville, Ga.
Humidity affects not only the climate within a store but also refrigeration systems, noted Churchill. "We recently completed a study that confirmed that the optimum humidity level in a supermarket should be in the 40% to 45% range," he said. "If it is higher, you are spending too much on refrigeration. If it is lower, the energy expended to lower humidity outweighs the return."
Winn-Dixie has always used air conditioning to make it easier on the refrigeration system, said Watson. "More humidity means more ice on the coils, so a shorter defrost means no ice-up and no downtime. This is important for the meat cases especially." In addition, he said, the chain uses HVAC to achieve positive pressure so that "air would puff out of the supermarket's door when it opens instead of blow out."
Albertsons' new equipment includes energy-efficient Carriers and Munters air-conditioning systems, which "extract more humidity out of the store environment than the traditionally designed system," said Moore. "This allows the refrigerated case system to run shorter amounts of time, and decreases the defrost cycles."
Seasons-4 offers a switchable subcooling system that increases the moisture-removing capacity of an air-conditioning system by 10% to 20%, going on and off to adjust to the humidity level, said Churchill.
Computers are being used more to manage HVAC systems, controlling valves, coils, compressors, dampers and carbon dioxide sensors, said Churchill. Controls are being designed to react to the weather, humidity and building pressure.
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