The Santa Clara system will eliminate all direct greenhouse gas emissions from refrigeration, thereby preventing emissions of more than 7,000 metric tons of CO2 equivalent from a comparable HFC system – more than the electricity use of 1,000 homes.
“This is one of the most significant steps in decades in the quest for more sustainable refrigeration systems,” said Liz Whiteley, executive director of the North American Sustainable Refrigeration Council.
The cascade system uses propane to condense the CO2. The CO2 is then piped through the refrigeration system to provide cooling.
Due to the unique properties of the CO2, only a limited amount of refrigerant is required. you do not need to use that much refrigerant, and also it generates a lot of heat during the refrigeration process.
Whole Foods decided to capture the heat generated during the refrigeration process via a heat reclaim system, which preheats water for later use in the store. The hot water also contributes to space heating. Whole Foods is no longer as dependent on natural gas to heat the store.
“Ultimately, the system uses the least possible amount of the most climate-friendly refrigerants in a format that both reduces the energy it takes to operate it and re-uses the heat its operation generates,” said Tristam Coffin, sustainable facilities coordinator for Whole Foods Market Northern California.
“There is precedent for this type of system in North America and Europe, but this is the first installation of the technology in the U.S. It’s a natural fit for Whole Foods Market to help design and launch it in California because we’ve invested in environmental advancements as an ongoing business practice.”
California has been very forceful in cutting emissions, especially from refrigeration. The Governor of California, Jerry Brown, has already committed to a directive to reduce state greenhouse emissions to 40% below 1990 levels by 2030.
Ryan McCarthy, Science and Technology Policy Advisor at the California Air Resources Board, said: “Cutting emissions of potent short-lived climate pollutants is one of the most important and immediate steps we need to take to address climate change, while we continue our rapid transition to clean energy, clean fuels, and zero emission vehicles.”
He added: “Whole Foods is showing the path forward for this industry, and that fighting climate change is good for business.”