U.S. EPA GreenChill Recognizes Transcritical CO₂ Stores at Kwik Trip and ALDI US

In its annual recognition awards ceremony on October 4, the U.S. Environmental Protection Agency (EPA) GreenChill Advanced Refrigeration Partnership presented awards under its Store Certification Program to Kwik Trip and ALDI US for stores that use transcritical CO₂ (R744) systems.

Hillphoenix, the leading U.S. provider of transcritical CO₂ systems, was also recognized.

The ceremony, during which awards were also given to 10 other food retail companies for their refrigerant-leak management practices, took place at the FMI (Food Industry Association) Energy and Store Development Conference in Baltimore, Maryland, held October 2–4.

Presenting the awards were Kirsten Cappel, Senior Environmental Policy Analyst and Lead for GreenChill at the EPA, and Chris Orvin, Program Analyst at the EPA.

Founded in 2007, the GreenChill Partnership is a voluntary program in which the agency works with food retailers to lower their refrigerant leak rates and help them transition to environmentally friendly refrigeration systems. In 2022, there were 35 food retail companies encompassing 13,262 stores – about one-third of the supermarket industry – in the program, as well as five system manufacturers and seven chemical producers. Member stores’ leak rates averaged 13% in 2022, compared to 25% or the U.S. supermarket industry as a whole.

GreenChill’s Store Certification Program recognizes stores with Silver, Gold and Platinum certifications for meeting increasingly strict refrigerant leak and charge criteria as well as those using refrigeration systems with minimal potential impacts on the ozone layer and climate system. The 2023 awards under this program cover certifications granted from July 1, 2022, through June 30, 2023. During this period 915 stores earned certification – a 13% increase from the previous cycle – including 710 Platinum, 89 Gold and 125 Silver,

This year’s GreenChill Store Certification recognition for Store Leadership went to convenience store chain Kwik Trip for its store in La Crosse, Wisconsin, which uses a transcritical CO₂ rack system from Hillphoenix. The store, which opened in June 2022, is being honored “as the first convenience store to receive a GreenChill Certification,” said GreenChill in a statement. Receiving the award was Carl Klemp, Kwik Trip’s Senior HVAC/R Engineer.

Wisconsin-based Kwik Trip, which operates over 800 convenience stores across Illinois, Iowa, Michigan, Minnesota, South Dakota and Wisconsin, has one other store using a transcritical CO₂ rack system (from Zero Zone, with Copeland compressors), at a new store in Dayton, Minnesota. Klemp described this system in a presentation at the ATMOsphere (ATMO) America conference, held in Washington, D.C., in June. The chain is one of the first U.S. convenience store operators to install transcritical CO₂ equipment.

At the GreenChill ceremony, Klemp told R744.com that Kwik Trip planned to install transcritical CO₂ systems at 17 stores in 2024. At ATMOsphere America, he said the chain has committed to transcritical CO₂ in all of its new and remodeled stores starting in July 2024 and will conduct its first retrofit with CO₂ this winter.

Historically, the GreenChill award recognizing a single certified store has gone to one using a natural refrigerant-based system.  Last year it went to a remodeled Target outlet in Vista, California, employing a transcritical CO₂ system. However, according to GreenChill data, in 2022 just 2.3% of GreenChill member stores (305), used CO₂ systems, compared to 14.6% (1,942) that employed an HFO/HFC blend (R448A or R449A). The rest used an HFC or R22 (less than 10%).

ALDI US and Hillphoenix triumph again

The 2023 GreenChill recognition for Store Certification Excellence went to Batavia, Illinois-based discount chain ALDI US for certifying 628 stores during the past year, more stores than any supermarket chain has previously certified, all at the Platinum level. It is the fifth consecutive year ALDI US, which operates more than 2,000 stores, in the U.S., has received this award. Last year, ALDI certified 505 stores at the platinum level.

Receiving the award on behalf of ALDI US were Amber Hardy, Director of Systems & Sustainability, and Chris Smyser, Manager of Building Systems.

Of its 628 GreenChill certified stores, all but about 10 use a transcritical CO₂ system; the others employ self-contained propane (290) cases throughout the store, according to Hardy and Smyser. ALDI US, which is the leading retail adopter of transcritical CO₂ in the U.S., is installing transcritical CO2 in about 70 to 100 stores annually, including both new and remodeled stores, noted Hardy.

Hillphoenix, based in Conyers, Georgia, also received a Store Certification Excellence award – for the 11th consecutive year – as the commercial systems manufacturer with the most systems installed in GreenChill Certified Stores in the last year, including many ALDI US stores.

Receiving the award for Hillphoenix, a founding member of GreenChill, was Scott Martin, Senior Director of Industry Relations and Compliance. In remarks at the ceremony, Martin pointed out the contributions GreenChill has made to the supermarket industry, including best-practice guidelines on leak-tight installation of commercial refrigeration equipment.

Six retail chains received Store Recertification Excellence awards for 118 stores that have been GreenChill certified at any level for five consecutive years. These include ALDI US (for 109 stores), Meijer (one), Publix Super Markets (five), Target (two) and Weis Markets (one). In addition, Hannaford’s Turner, Maine, store, which installed the first transcritical CO₂ system in the U.S. in 2013, was recognized for recertifying that store for 10 consecutive years.

During his presentation at the awards ceremony, Orvin of the EPA said that the agency has formed a Store Certification Workgroup to discuss “potential changes to store certification criteria with partners.” The group, which includes nine retail partner companies, four equipment manufacturers and four chemical producers, is looking at:

• Adjusting existing criteria (making it more stringent) vs. including new criteria, such as incorporating GWP-weighted emissions and/or charge-to-load ratios, and/or a reclaim component;
• Making a distinction between new stores and existing stores in certification;
• The meaningfulness of the low-GWP pathway to platinum;
• Basing methodology for new criteria on a top-down (scenario-based) or bottom-up (data-based) approach.

The EPA plans to announce the new criteria “well in advance of the 2024 store certification cycle beginning July 1, 2024,” said Orvin.

Leak-reduction awards

The GreenChill program also presented partnership program awards for refrigerant-leak-reduction achievements that occurred during the 2022 calendar year.

• Best Emissions Rate for the lowest refrigerant emissions rate of all retail partners: Ashland Food Co-Op, based inAshland, Oregon, in the small independent category; and Meijer, based inGrand Rapids, Michigan, in the retail chain category.
• Most Improved Emissions Rate for commercial systems from the previous year and baseline year: Brookshire Grocery Company, based in Tyler, Texas.
• Superior Goal Achievementfor achieving the annual refrigerant emissions reduction goal, which must be below the leak rate achieved the year before: Ashland Food Co-Op; Brookshire Grocery Company, Food Lion, based in Salisbury, North Carolina; The Giant Company, based inCarlisle, Pennsylvania; Hannaford, based inScarborough, Maine; King Kullen, based inBethpage, New York; and Weis Markets, based inSunbury, Pennsylvania.
• Exceptional Goal Achievement for achieving a “stretch” refrigerant emissions goal, which is more difficult to achieve than a superior goal: Ashland Food Co-Op and Food Lion.

“Participants in the GreenChill Partnership and Store Certification Programs have been leading the industry in environmentally friendly refrigeration practices, and EPA annually honors their achievements at both the corporate and individual store certification level,” said Paul Gunning, Director of EPA’s Office of Atmospheric Protection, in a statement. “These companies’ efforts show that it is possible to keep food cool while protecting our Earth’s ozone layer and climate system by setting and achieving ambitious goals year after year.”

“Participants in the GreenChill Partnership and Store Certification Programs have been leading the industry in environmentally friendly refrigeration practices.”

Paul Gunning, Director of U.S. EPA’s Office of Atmospheric Protection