At BriarPatch Food Co-op, a two-store grocery cooperative located north of Sacramento, California, HFC refrigerant leaks “represent the largest single source of greenhouse gas emissions,” according to its website.
As such refrigerants are “our greatest opportunity to clean up our act—and we have a plan,” said the 49-year-old Co-op, which has about 11,000 members. “Our goal is to move to climate-friendly refrigeration systems and cut leak rates in our existing HFC system by 50%. And we’re on track to do just that!”
At its 10,000ft2 (929m2) store in Auburn, California, which opened in August 2023, BriarPatch installed a transcritical CO2 (R744) natural refrigeration system from OEM Hillphoenix, avoiding the use of HFCs altogether. “Only 2% of U.S. grocery stores currently use this technology,” the Co-op reports on its website. (According to “Natural Refrigerants: State of the Industry 2024,” published by ATMOsphere, there are about 2,800 U.S. stores using transcritical CO2 systems, or 4.2% of U.S. supermarkets and grocery stores; ATMOsphere is publisher of NaturalRefrigerants.com.)
West Coast contractor Key Mechanical did the installation of the CO2 system, and handles maintenance as well. The system incorporates parallel compression and an adiabatic gas cooler to improve efficiency during warm ambient temperature periods. The cost of the system was more than $200,000 (€176,593) more than that if a traditional HFC system, noted Lauren Scott, BriarPatch’s former Sustainability Coordinator, in a webinar presentation last year. “But we felt it was a really worthwhile investment,” she said.
The Co-op did not receive outside funding for the CO2 installation at the Auburn store but is looking into funding from the state of California for a future CO2 retrofit at its other 10,000ft2 store in nearby Grass Valley. “The funding isn’t as significant as we need it to be so hopefully we can get there in the future,” said Sasha Scott, BriarPatch’s current Sustainability Coordinator, adding, “it’s a huge project to do the retrofit.”
“As we grow and do remodels in the future, we will try to work in transitioning over to CO2 for new equipment.”
Dave Thomas, Facilities Manager for BriarPatch Food Co-op
BriarPatch’s decision to install a transcritical CO2 refrigeration system in its Auburn store was motivated by its sustainability mission, including not wanting to “add more toxins into the atmosphere,” said Dave Thomas, Facilities Manager for BriarPatch, in an interview with NaturalRefrigerants.com. Another factor was California’s strict HFC regulations. “So we decided to make the big jump,” he said.
The CO2 system in Auburn has been performing as well or better than BriarPatch’s legacy system, said Thomas. Key Mechanical had to “work out some little bugs” such as defrost programming over the first six months of operation but since then there have been “very few problems.” There have been no significant leaks of CO2, though Thomas keeps a supply of the gas on hand in the event of a major leak. “The availability of [CO2] can be tricky,” he said.
The Co-op also employs propane (R290) stand-alone fridges in its deli prep-food area in both stores and R290 stand-alone cases in Auburn and as replacement cases in Grass Valley.
EPA GreenChill member
BriarPatch’s Grass Valley store opened in 2007 following other locations in the town. There, the Co-op is working diligently to reduce emissions of R404A through preventative maintenance and in-house leak detection. It is also a “proud member” of GreenChill, a voluntary U.S. Environmental Protection Agency (EPA) program that works collaboratively with food retailers to reduce refrigerant emissions and transition to environmentally friendly systems including those using natural refrigerants.
For leak detection, the Co-op purchased a Bacharach H-10Pro digital leak detector.
In 2024, GreenChill presented BriarPatch with an award for the most improved emissions rate (year-to-year). It also received platinum certification for its Auburn store based on its use of CO2 refrigeration.
At the Grass Valley Store, which has LEED (Leadership in Energy and Environmental Design) certification, BriarPatch is transitioning to lower-GWP drop-in replacement R448A and eventually plans to replace the current system with a transcritical CO2 system, said Thomas. “As we grow and do remodels in the future, we will try to work in transitioning over to CO2 for new equipment.”
The Co-op’s Grass Valley store employs a 680-panel, 296kW solar array over the parking lot that generates about half of the store’s electricity, said Scott. At both stores most cases have doors to save energy.
2025 environmental goals
In 2020, BriarPatch set environmental goals for 2025, including using 100% renewable energy and reaching net zero emissions. “We’re continuing to make progress towards achieving our 2025 goals and lowering our impact in other areas as well, like water conservation,” the Co-op says on its website. “Sustainability is at the core of how we make business decisions at BriarPatch.
The Co-op also seeks “to act as a leader among local businesses and food co-ops nationally and contribute to environmental stewardship through our business practices,” it says on its website.
BriarPatch is part of the National Co+op Grocers (NCG), a business services cooperative for retail food co-ops located throughout the U.S. NCG represents 165 food co-ops operating 241 stores in 39 states with combined annual sales over $2.8 billion and serving over 1.3 million consumer-owners. BriarPatch is also a member of the Climate Collaborative, a nonprofit promoting climate action in the grocery industry.
Other food co-ops are showing interest in installing transcritical CO2 systems as well, including the Brattleboro (Vermont) Food Co-op and the Ashland (Oregon) Food Co-Op.
