WASHINGTON — Alternative refrigeration systems using natural refrigerants such as carbon dioxide (CO2) are within reach of supermarket retailers from a cost and implementation perspective, though challenges remain, said a panel of supermarket executives at ATMOsphere America 2012, a conference on the business case for natural refrigerants held here last week at the Liaison Capitol Hill Hotel.
Natural refrigerants, such as ammonia, carbon dioxide (CO2), propane and other gases, have a negligible or zero impact on global warming as well as no effect on the ozone layer. As a result, they are being considered by food retailers worldwide as a replacement for both R-22, the primary refrigerant used by food retailers that is being phased out due to its harmful effect on the ozone layer, and HFC (hydrofluorocarbon) refrigerants, which have a high global warming potential.
Simon Bérubé, senior director of engineering and commercial development for Sobeys  Quebec, which has pioneered the use of CO2-based transcritical refrigeration systems in more than 20 stores, acknowledged the cost issues associated with an initial installation; however, over time and multiple installations, Sobeys has found the cost to come down.
“The renovation of a 24/7 store with CO2 systems has become cheaper than the cost of a new store that I was buying one year ago, so there has been a huge improvement in the cost,” Bérubé said. He also noted that Sobeys has cut its food loss by 1% because of the better cooling performance of its cases using the new system.
Whole Foods Market , Austin, Texas, has been hearing that start-up costs for CO2 are “better than with other systems,” said Kathy Loftus, global leader of sustainable engineering and energy management for Whole Foods Market. However, Richard Heath, senior manager, technology integration for Supervalu  in its Boise, Idaho, office, disputed that, pointing to the high installation costs of the systems.
Still, Heath said he believed all the retailers at the conference could utilize systems that employ at least 90% natural refrigerants right away. “For new stores, there’s no reason not to be all natural,” he said, adding that affordability may be an issue for remodels.
Loftus noted that in some parts of the U.S. it’s difficult to install natural refrigerant systems because of the lack of technicians who know how to service these systems. Whole Foods decided against a CO2 system in North Carolina for that reason, she said. But Harrison Horning, director of energy and facility services for Delhaize America , Scarborough, Maine, pointed out that training webinars are available from the Environmental Protection Agency’s GreenChill program, as well as training from refrigeration vendors.
The ATMOsphere America 2012 conference was organized by Shecco, a Belgium-based B2B marketing firm.