A Surge Of Less Energy


According to Kilojolts Consulting Group, $1 energy shrink = $40 equivalent sales

Foodretailers are becoming more proactive in containing energy costs, reaping both economic and environmental rewards.

Reddy Kilowatt, the stick-figure cartoon that represented electric companies for much of the 20th century, would be pleased with the following comments.

“Whether it's using new refrigerants with a lower global warming potential (GWP), using more energy-efficient lighting fixtures combined with more skylights for natural daylight, or reducing the amount of waste they send to the local landfill, supermarkets are working harder than ever to overcome the often negative press they receive for their above-average use of energy and other environmental resources, compared to other types of retailers,” says John Weisenberger, director, grocery segment marketing at Novar, a Cleveland-based Honeywell company that has been reducing energy costs for more than 20 years for retailers such as Brookshire Bros., Riesbeck, Save-A-Lot, Walmart and Carrefour.

“Supermarkets that build an energy management strategy into their overall business plan see substantial financial rewards,” affirms Weisenberger.

Gary K. Markowitz, president of Kilojolts Consulting Group in Lexington, Mass., whose clients include Safeway, Stop & Shop, Big Y and C&S Wholesale Grocers, is a former corporate energy manager for Star Markets Co. “I learned firsthand that energy management is an essential part of controlling the operating budget,” says Markowitz, noting that when his company approaches supermarkets with an economic-based energy management strategy, “we communicate in terms that a store manager can understand: $1 energy shrink equals $40 equivalent sales.” (The government-backed “Energy Star” program estimates that $1 in energy savings is equivalent to increasing sales by $59.)

Markowitz says that even a 10 percent reduction in energy consumption can be like trimming a store's energy bill by $25,000 or more a year. “Using our $40-to-$l equation, that's equivalent to improving gross sales by almost $1 million,” he notes.

Dean Cromwell, director of new business development at Aztec Energy Partners in Conyers, Ga., which boasts clients such as Supervalu, Safeway, Walmart, Winn-Dixie, Ahold, Giant Eagle, Food Lion, Coles (Australia), Wegmans and Albertsons, adds: “As energy prices continue to trend upward, supermarket companies are continuing to become more sophisticated, and are generally paying more attention to energy-use reduction, carbon footprint reduction and sustainability.”

At E Source in Boulder, Colo., Research Manager Mary Horsey points out: “Being seen as green by their customers and local community can result in more customer traffic, increased sales and an increased profit for supermarkets.”

Targeting Waste

Novar's Weisenberger notes that supermarket HVAC, lighting and refrigeration systems have long been the targets of energy conservation measures, as they typically drive the bulk of a store's energy consumption. He says that Novar's recommended approach to energy management follows the adage “You can't manage what you don't measure,” and “at minimum, some amount of metering should be installed in each of the three areas, allowing the collection of energy-use data to identify problem sites. From this meter data, a comprehensive energy management strategy can be developed to reduce the overall energy consumption of any problem area.”

E Source's Horsey says that refrigeration and lighting represent about 80 percent of a store's total electricity use, and has the following suggestions to optimize refrigeration and reduce lighting costs:

■ One study found that the implementation of a floating-head pressure-control system for refrigeration produced annual savings of up to $15,000.

■ For refrigerated display cases, anti-sweat heater controls save more than $27,000 in a typical grocery store.

■Display case shields, also known as night covers, can reduce the daily refrigeration load from the display case by 8 percent when applied overnight.

■Many grocers use heat-recovery systems to capture waste heat from refrigeration systems to make hot water for use in the store. The hot water can be run through a heat exchanger for space heating in cold weather.

Here Comes the Sun

The ShopRite supermarket in Egg Harbor Township, N.J., that will open by the end of this year will be outfitted with a new solar-power system from The Solar Center in Rockaway Township, N.J., to reduce energy consumption and lower the environmental impact of the store, joining two other ShopRites with installations from The Solar Center.

The environmentally based initiative will consist of the installation of 1,782 solar panels — each fixed to the roof of the store — and will produce 525 kilowatts, which will power in-store refrigeration and lighting. The new solar panel system is also expected to reduce energy consumption at the store, reducing carbon dioxide emissions by 400 tons.

“The solar project allows us to build sustainable practices into our business while still providing quality service and comfort to our customers,” says Kevin Begley, CFO of Springfield, N.J.-based Village Super Market Inc., which owns and operates the Egg Harbor Township location and is part of the Wakefern Food Corp. retail cooperative based in Keasbey, N.J. “We recognize that our customers look for a shopping experience that not only offers them service and value, but that also fulfills their desire to do what's right for the environment.”

In addition to installing solar panels, the Egg Harbor Township store uses high-efficiency refrigeration systems and refrigerated display cases with energy-saving lamps and lighting systems to lessen the impact on the environment.

“Being seen as green by their customers and local community can result in more customer traffic, increased sales and an increased profit for supermarkets.”

— Mary Horsey, E Source

■When installed in walk-in freezers, smart defrost controllers monitor several variables and optimize the number of daily defrost cycles.

■When Walmart replaced conventional fluorescent T8 lamps in its refrigerated cases with light-emitting diodes (LEDs) in fixtures tied to occupancy sensors, energy consumption by refrigerated case lighting dropped by about 70 percent and the lights were on about 60 percent of the time.

■Dessicant dehumidification can be a cost-effective solution for air conditioning in humid climates, because it uses natural gas instead of electricity to remove moisture from the air. Also, with dessicant dehumidification, air-conditioning equipment can sometimes be sized smaller because it's used only to cool dry air.

■ For store-wide ambient lighting, efficient linear fluorescent systems — either T5 lamps or high-performance T8 lamps — can reduce energy consumption by 355 percent or more compared with T12 lighting. In high-bay areas and big-box stores with ceilings higher than 15 feet, high-performance T8 and high-output T5 lamps are the most efficient approaches. Horsey adds this caveat: “Recently, LEDs have emerged as an even more efficient option than high-density lighting. However, because of the high initial price, many stores might find that LEDs do not yet offer suitable returns. Future price reductions and Energy Star standards will likely spur more widespread adoption of LEDs.”

Current and Future Improvements

Further strides in HVAC and refrigeration technology have resulted in reduced supermarket energy consumption. Among them, according to Aztec's Cromwell, are high-efficiency compressors, high-efficiency fan motors, greater use of variable speed drives, greater use of smart-control algorithms, and more sophisticated monitoring and benchmarking of energy usage.

Kilojolts' Markowitz says: “We're seeing improvements in refrigeration rack controls, including variable-frequency drives, new digital defrost cycle controls for refrigerated boxes, and lower-cost LonWorks HVAC digital controls.”

“Energy management is an essential part of controlling the operating budget.”

—Gary K. Markowitz, Kilojolts Consulting Group

On the fringes, he continues, “we've been hearing about some improvements users can make to existing compressors through oil-refrigerant separator additives to improve thermodynamic performance, and there's been some good buzz regarding a new food-density temperature sensor controller designed to maintain the temperature of the refrigerated boxes on the basis of the food temperature, not the box's air temperature. We have not tested the additives or the new temperature controls yet, but they sound very promising.”

Novar's Weisenberger, meanwhile, says that new technologies like LED lighting, electronically commutated motors (ECMs), variable-frequency drives and advanced compressor management systems have all gained wider supermarket adoption in the past five years. “However, use of each of these component point solutions' alone is not enough to drastically 'move the needle' on a supermarket's total energy consumption,” especially with supermarkets adding in-store bakeries, delis, bistros, coffee bars, pharmacies, medical clinics, bank branches and other departments that also have high energy needs.

“Integration of these components into a complete supermarket building automation system is key to delivering on the total energy savings possible,” observes Weisenberger. New software information technologies, he notes, are also playing a major role in the reduction of supermarket energy consumption.

As supermarkets continue to evolve into multifaceted retail operations with an increasingly wider variety of energy-consuming departments and devices, all located within a common building envelope, Weisenberger says: “The need for energy management systems capable of integrating a wider variety of equipment into a holistic supermarket building automation system will become an absolute necessity.” PG

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