Natural refrigerant systems used in supermarkets were once again cited in the Annual Recognition awards program presented online on September 9 by the U.S. Environmental Protection Agency’s GreenChill Advanced Refrigeration Partnership.

The GreenChill program, launched in 2007, is a voluntary partnership between the EPA and primarily U.S. food retailers, designed to help them reduce their refrigerant leaks and transition to climate-friendly refrigeration, including natural refrigerant systems. It comprises 28 food retailers operating 12,900 stores, about a third of the U.S. total.

GreenChill store certification program recognizes individual stores – participating in GreenChill or not – that meet leak and charge requirements or use climate-friendly refrigerants.

Grocery Outlet, based in Emeryville, California, received the Store Leadership award for a store in Canoga Park, California, which is the first GreenChill certified store to use exclusively R290 in its refrigeration.

Grocery Outlet’s stores operate under an owner/operator model, with owners partnering with the corporation. The banner is thus used at more than 400 stores, mostly on the West Coast of the U.S., with some in the Mid-Atlantic and New England regions. Grocery Outlet corporate designs and monitors refrigeration systems for the stores.

To date, four Grocery Outlet stores use R290 self-contained “microdistributed” cases throughout the sales area, and a fifth is getting ready to open on the East Coast, according to Frank Davis, Director of Refrigeration Engineering, Energy & Sustainability for Grocery Outlet, who spoke during the awards presentation. The cases were provided by AHT Cooling Systems USA.

“We are analyzing whether to proceed with more [R290 stores],” Davis said. The R290 cases “are running nice in Canago Park.”

Each of the circuits in the self-contained cases contain less than the 150g charge limit for R290; larger cases with up to 12 doors use up to three circuits. The cases employ a waterloop (glycol) system to remove heat of condensation, in concert with a roof-mounted fluid cooler.

Davis noted that refrigeration technicians are able to maintain the self-contained cases, but they struggle with the proprietary software.

Grocery Outlet has a store in East Sacramento, California, that uses a transcritical COsystem. With stricter refrigerant regulations coming to California in 2022, the company has made transcritical CO2 “our spec for now” at new stores in the state, said Davis. Adiabatic gas coolers will be used, though not in stores that don’t need them because of cooler climate conditions. Grocery Outlet is also looking at ejectors and parallel compression for stores in warmer climates.

Because many Grocery Outlet stores are located in small towns in Northern California, with limited contractor resources, the company still struggles to find suitably trained technicians to work on transcritical CO2 systems in those stores, Davis said. “So training is a high priority.”

Grocery Outlet has been using predictive analysis tools to identify leaks before they become large, Davis said. At one store this year in Northern California, a tool from Axiom Cloud enabled Grocery Outlet to detect a small leak of an HFC refrigerant, saving the company an estimated US$4,790.

Tools like this are especially helpful given the “struggle to get new technician talent,” Davis said.

424 certified ALDI US stores

The Certification Excellence award, given to the food retailer with the most GreenChill-certified stores between July 1, 2020 and June 30, 2021, went to Batavia, Illinois (U.S.)-based ALDI US, which operated 424 certified stores during that period, all at the platinum (highest) level; ALDI US’ total is nearly two-thirds of all GreenChill certified stores (662). This is the third year ALDI US has received the Certification Excellence award.

ALDI US was also given GreenChill’s Store Recertification Excellence award, for operating 31 stores – mostly in California and New York – that have been recertified for at least five consecutive years, the most of any GreenChill retail partner.

Many of ALDI US’s certified stores use natural refrigerants, typically transcritical CO(R744) as the primary system, along with eight to 10 spot merchandiser freezer units that operate on R290 (and are also used in most other stores throughout the chain).

ALDI US, a division of German retail giant ALDI Süd, reported in June that it had installed transcritical CO2 (R744) refrigeration at 423 stores – the most of any supermarket chain in the U.S. The chain has also installed only R290 self-contained semi plug-in display cases with a glycol loop to remove heat of condensation at two stores, and only R290 air-cooled plug-in cases at one store.

ALDI US, which operates more than 2,000 stores across 36 U.S. states, is continuing to roll out natural refrigerant systems in new and remodeled stores.

Conyers, Georgia (U.S.)-based OEM Hillphoenix also received a Store Certification Excellence award for being the manufacturer that has supplied the most systems to certified stores between July 1, 2020 and June 30, 2021. According to ALDI US, Hillphoenix has provided ALDI US with approximately 380 of its 423 transcritical CO2systems, This is the 10th year that Hillphoenix has received this award. 

Also receiving a Store Recertification Excellence award was Phoenix, Arizona (U.S.)-based Sprouts Farmers Market, which operates 21 stores that have been recertified for at least five consecutive years. Sprouts, which operates 365 stores in 23 states across the U.S., is installing transcritical CO2 in all new California stores, according to Justin Kacer, Sustainability Manager at Sprouts, who spoke during the GreenChill awards ceremony.

Leak reduction awards

The GreenChill program also gave out awards to retailers recognizing progress in reducing refrigerant leaks during the 2020 calendar year:

  • The Superior Goal Achievement award, which goes to retail partners that achieve their annual leak reduction goal (which must be lower than the rate achieved the prior year), was given to Cook County Whole Foods Coop, Food Lion, Grocery Outlet, Hy-Vee, Meijer, Raley’s, Sprouts Farmers Market and Target.
  • The Exceptional Goal Achievement award, which is given to retailers that achieved a “more aggressive” leak reduction goal, went to Hy-Vee and Meijer.
  • The Most Improved Emission Rate award, based on improvement from the prior year, was given to City Market Onion River Coop.
  •  The Most Improved Emission Rate award, based on improvement since the year the retailer joined GreenChill, went to Weis Markets.
  • The Best Emissions Rate award for a retail chain was presented to Meijer; the same award for a small retailer went to Cook County Whole Foods Coop.

“Training is a high priority.”

Frank Davis, Grocery Outlet

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