In supermarket refrigeration, much of the refrigerant talk is on the so-called ‘naturals.’ And among the naturals, one of the most talked about is R-744 (CO₂). And when talking about ways to use it, the most often discussed approach is in transcritical applications. That thought process formed the basis for a supermarket end-user panel discussion this summer in Washington, D.C., at the second Atmosphere America Natural Refrigerants Conference. Participants came from Dehaize America (which owns the Food Lion chain), Sobeys, Sprouts, SuperValu, and Whole Foods, amongst others.

While transcritical CO₂ was most discussed, other applications gaining attention were systems running on CO₂ subcritical, CO₂/cascade, and ammonia/hydrofluorocarbons (HFCs). The panelists talked not only about the practical aspects of getting these new systems up and running, but at what cost, how to justify those costs, and how the approach meshes with corporate statements concerning environmental stewardship.

Moderator Keilly Whitman, who — until taking the position of vice president of marketing with EOS Climate, a company involved in refrigerant life cycle management — headed the Environmental Protection Agency’s (EPA) GreenChill Advanced Refrigeration Partnership, a program that works closely with supermarkets and suppliers in developing energy-efficient and environmentally favorable equipment.

Forecasting the Future

The panel’s first question centered on the future of natural refrigerants in the supermarket sector.

“The feeling is one of high hopes,” said J’aime Mitchell, green mission specialist, Whole Foods Market, which is involved in both transcritical CO₂ and CO₂ subcritical. “We are moving forward and are really excited about the transcritical possibilities.”

But, cautioned Steve Hagen, procurement manager, Sprouts Farmer’s Market LLC, which uses CO₂ cascade, “In any natural refrigerant project, the cost equation comes into balance.”

Richard Heath, experienced retail energy and refrigeration professional, capital deployment specialist, Source Refrigeration — speaking on behalf of SuperValu Inc., which has an ammonia/HFC refrigerant store — said, “It’s not all or nothing when it comes to natural refrigerants. We can still be 90 percent natural, even when using a synthetic refrigerant like an HFC.”

Rod Peterson, national procurement manager, refrigeration and HVAC, Sobeys Inc. — a Canadian supermarket chain, which is involved in both transcritical and cascade systems — said, “There is a much better awareness of transcritical systems, and we are pleased to see transcritical being piloted in the U.S. I see some huge leaps forward.”

Mike Guldenstern, design team member, Whole Foods Market, which is involved in using natural refrigerants in conjunction with HFCs, sees a combination of HFCs and naturals as a way to lower the amount of f-gas needed in a system. “We’ve gone deep into HFCs on the highside, and we are getting the return and numbers,” he said — referencing the resulting cost and energy efficiency. He noted his company works with focus groups based on the area of the country in which stores are planned. Even now, he said, talk of natural refrigerants is not a complete foreign language anymore.

Read more: http://www.achrnews.com/articles/124281-supermarket-talk-turns-natural