Recently, we’ve been working on new construction for Sprouts Farmer’s Market, a specialty grocery concentrated on healthy living. Their management team places a focus on lowering carbon footprint, and we’ve been a part of those efforts in regards to refrigeration.
The old standard HFC refrigerant has a number of environmental concerns and regulatory pressures have added economic justification to the move away from it. The best alternative to HFC is carbon dioxide (CO2).
In the north Atlanta store, we’re installing an advanced technology booster system that uses CO2 (R-744) to naturally cool through a process called adiabatic condensing. This condenser uses water as a coolant. As the outside air passes through, water absorbs heat. This effectively lowers the temperature needed to cool and, under most conditions, condenses the CO2 in the system. It’s the same process that creates cloud formations in the atmosphere.
The difference between adiabatic condensers and other types of water-cooled condensers is that the coils stay dry, reducing maintenance and water usage. When compared to the dry gas cooler typically used with booster systems, the adiabatic condenser is able to use a lower “dry bulb” temperature to cool the CO2. The advantage? CO2 can to continue condensing in warmer conditions longer than it would otherwise, translating to lower energy usage.
Overall, the technology reduces the carbon footprint of the store’s refrigeration to near zero. For companies like Sprouts that focus on sustainability, the CO2 booster system makes perfect sense. We expect to see more similar installations in the years to come.
For more information, this CO2 System profile from Hill Phoenix is very informative.
