The average grocery store’s refrigeration system uses about 3,500 pounds of refrigerant—called a “charge”—and leaks about one-quarter of it, or 1,000 pounds a year, according to the EPA. “That 1,000 pounds of greenhouse gas is 1,800 to almost 4,000 times more potent than carbon dioxide,” says Keilly Witman, manager of the EPA’s GreenChill Partnership, which works with food retailers to cut their refrigerant emissions and reduce their impact on the ozone layer and climate change.
The EPA is requiring that R22, the most common refrigerant in standard refrigeration systems, be completely phased out by 2020, so change is on the way. Stores are primarily replacing R22 with hydrofluorocarbons such as R404A and R507, which do not harm the ozone layer, Witman says. New refrigeration technologies and practices can offer another benefit beyond environmental protection: They save money. Leaking refrigerant costs about $7 to $10 a pound.
“Cutting refrigerant emissions is the right thing for retailers and it’s the right thing for the environment,” says Jerry Stutler, vice president of construction and facility engineering at the Phoenix-based Sprouts Farmers Market chain. Sprouts is a GreenChill partner and has received certification for seven of its 54 stores.
GreenChill aims to cut emissions
Established in 2007, the free GreenChill Partnership program is a voluntary alliance of more than 7,000 grocery retailers, refrigeration systems manufacturers and non-ozone-depleting refrigerant companies committed to switching to more environmentally-friendly refrigerants, cutting or eliminating refrigerant leaks and adopting greener strategies and practices. Corporate grocery chains that track refrigerant emissions and set goals for reducing emissions can participate in the Corporate Emissions Reduction Program. Manufacturers of advanced refrigeration systems and non-ozone-depleting commercial refrigerant manufacturers also can participate.
In addition, GreenChill offers a certification program that recognizes individual stores for using greener commercial refrigeration systems. Stores can achieve silver, gold or platinum certification based on a set of requirements for charge size and leak reduction. To achieve GreenChill Store Certification, a store must emit at least 65 percent less refrigerant than the average supermarket. Witman says GreenChill partners average a 12 percent annual leak rate compared to the approximate 25 percent leak rate at average U.S. stores.
“If every store in the nation reduced its leak rate to the GreenChill average of 12 percent, the country would save more than $100 million every year just in the cost to refill refrigerant because it’s leaking,” she adds. GreenChill also has an Advanced Refrigeration Program that promotes guidelines for best practices. And partners in the program share information and strategies and have access to industry resources.
Stutler says Sprouts joined GreenChill in 2009 to take advantage of the technology and resources offered and find ways to cut emissions. “Everybody was a little suspicious of the program at first,” he recalls. “We suspected that the EPA was using GreenChill as an easy way to keep track of refrigerant loss,” as part of the agency’s requirements. “But it’s a great way to share ideas, technology and engineering. Now there’s a bit of competition among the retailers. Everybody wants to be the best.”
Cool new systems
Sprouts’ new stores are equipped with a distributed refrigeration system, which is one of a handful of technologies that improve upon the standard centralized direct expansion system used in most grocery stores. Witman says it’s difficult to estimate average costs for the systems because each system is individually designed and then manufactured according to the store’s specific specifications. But generally, the more technologically advanced the system, the greater the cost. The distributed refrigeration systems in the 25 new Sprouts stores, which are each about 25,000 square feet, cost about $180,000, not including labor, Stutler says.
Stutler points out that the savings are built in because many of the new systems rely on less copper piping, which is costly, all use less refrigerant and, of course, all are designed to leak less. He says the new systems cost about $5,000 to $7,000 more than older systems. In addition, Sprouts’ company-wide leak rate last year was 6.9 percent, one of the lowest among all GreenChill participants.
Refrigeration system manufacturers such as Hill Phoenix, Kysor Warren, Zero Zon and Hussman Corp. participate in the GreenChill program and were instrumental in helping develop the Store Certification Program. Stutler says these manufacturers are reliable experts in new refrigeration technology and can help retailers choose the best options for their stores.
Sprouts will continue to install advanced refrigeration systems in all of its new stores, and “as we get into remodeling stores that are in the 10- to 15-year-old range, we will change systems,” Stutler says. “But it will be another five to seven years before we start that. It’s not realistic [financially] to do it before then.”
Other ways to chill costs
Installing new, advanced systems is just one way grocers can cut refrigerant emissions. Down to Earth All Vegetarian Organic & Natural markets in Hawaii, which became, fittingly, the 50th GreenChill partner in fall 2010, has traditional refrigeration systems in its five stores and installed a traditional system in its sixth store, which opened this summer. Down to Earth CEO Mark Fergusson, known as the company’s chief vegetarian officer, says some of the newer advanced systems “aren’t very well tested yet and would cost $60,000 to $80,000 more than a traditional system.” Currently, no government subsidies or rebates help with costs for installing new systems.
Instead, Down to Earth has instituted a number of measures to track and cut leaks. Fergusson says his stores work with contractors that follow a “rigid installation system,” which includes using soldered joints instead of fittings. Although fittings can be cheaper and easier to use, they aren’t necessarily 100 percent leak free like soldered joints. In addition, Fergusson says Down to Earth’s refrigeration systems are installed with leak detectors equipped with an Internet alarm system that automatically notifies management if refrigerant levels drop, indicating a possible leak.
Although it’s too soon to measure exactly the environmental impact of Down to Earth’s efforts, Fergusson’s goal is to cut the stores’refrigerant loss by 10 percent this year. “We are actively working toward protecting the environment and reducing operating costs while we do it,” he says.
Refrigeration system options
1. Centralized direct expansion system.
Known as centralized DX, the equipment for this traditional refrigeration system is located in a store’s machine room. Refrigerant is circulated from the refrigeration equipment to the store’s cold cases and freezers by yards of copper piping that snakes throughout the store to refrigerator cases and freezers. Each system holds an average of 3,500 pounds of refrigerant, and all the pipes, joints and valves provide ample opportunity to leak, according to Keilly Witman, manager of the Environmental Protection Agency’s GreenChill Advanced Refrigeration Partnership. Although centralized DX systems have an average leak rate of about 25 percent, stores can monitor leaks and provide regular maintenance to reduce that number to about 10 percent to 15 percent, Witman says.
2. Distributed system.
Rather than one main system, smaller systems are located throughout the store near coolers and freezers, requiring less piping and refrigerant. Phoenix-based Sprouts Farmers Market uses this system in its new stores, and Vice President of Construction and Facility Engineering Jerry Stutler says each system uses about 600 to 800 pounds of refrigerant, and the company’s leak rate is 6.9 percent.
3. Secondary loop system.
Although the equipment is in a store’s machine room, two refrigerants are used. The primary refrigerant, usually an HFC, chills a secondary refrigerant that is then piped to coolers throughout the store. Because the HFC refrigerant stays in the machine room, there is less potential for leaks, and the leaks that do happen can be located faster and repaired easily. The secondary refrigerant is often glycol or carbon dioxide, which is less harmful than a primary refrigerant like the chemical R-404A, Witman says.The system uses about 1,000 pounds of HFC refrigerant, depending on the size of the store, and the leak rate averages about 5 percent, according to Witman.
4. Cascading CO2system.
Two independent refrigeration systems use different refrigerants depending on the temperature range needed. One part of the system brings the unit to medium cool. The other uses naturally occurring carbon dioxide to bring the unit to freezing. A new Sprouts store in Westlake, Calif., is the first in the chain to install a CO2system. Stutler says the system uses about 235 pounds of refrigerant. Leak rates range from zero to 5 percent, according to Witman. The system has a significantly lower global warming impact than conventional systems, according to GreenChill.
Green refrigeration tips
If you can’t afford new refrigeration equipment, you can still reduce the ill effects of refrigerants. Here’s how.
Use refrigerants that don’t damage the ozone layer. Replace R22 refrigerant, which must be phased out by 2020, sooner rather than later. Visit the EPA's GreenChill website for recommendations and guidelines.
Make sure equipment installation ensures against leaks. Use soldered joints rather than fittings, for example. Consult GreenChill’s Installation Leak Tightness Guidelines.
Institute mandatory monthly leak checks. Don’t just replace refrigerant when the system is low. Buy a handheld leak detector—most devices cost about $200—and use it around all pipes and display cases. You can find a leak and replace it before you notice a drop in the refrigerant level.
- Join the free GreenChill Partnership. Becoming a partner allows you to take advantage of information, resources, discussions and webinars, and learn from other partners. “There’s a wealth of information and resources available for all retailers,” says Jerry Stutler, vice president of construction and facility engineering for Phoenix-based Sprouts Farmers Market.