At a new store opening in December in Sleepy Hollow, New York, grocery operator DeCicco & Sons plans to generate space heating and dehumidification via a direct CO2 (R744) heat reclaim coil linked to a transcritical CO2 refrigeration system.
The “boosted” direct CO2 heat reclaim system – which diverts hot CO2 gas from rack compressors in a Hillphoenix CO2 refrigeration system – will be provided by Canadian HVAC OEM Flō Energy Solutions. The coil resides inside a DOAS+ HVAC unit using Adaptive Multi-Path Technology. This is in contrast to a “passive” heat reclaim system, which uses hot CO2 gas to heat a secondary fluid.
The Sleepy Hollow store will also use an air-conditioning system in the summer to supply subcooling to the CO2 rack, said John DeCicco Jr., President and CEO of the 10-store chain located in the suburbs just north of New York City.
Flō has provided its direct CO2 heat reclaim coil to about 1,000 stores in the U.S. and Canada, said Laura Semidey, its Director of Engineering & Innovation. The boosted version of the system, which enables the CO2 rack to modulate compressor head pressure in response to a heating demand signal from the heat reclaim coil, was recently introduced as a retrofit at a small-format store in Pennsylvania; the store cut its natural gas use for comfort heating during winter by 84% by replacing its passive reclaim coil with the optimized direct CO2 heat reclaim coil.
Flō has also found that its boosted coil can recover three times more waste heat from a supermarket’s refrigeration system than a standard passive heat reclaim approach.
Semidey said Flō plans to install the boosted coil in “dozens” of additional stores in the U.S. and Canada.
Every bell & whistle
DeCicco & Sons has installed transcritical CO2 systems in seven of its 10 stores, with plans to convert the other three to CO2 and install it in two new stores, including the one in Sleepy Hollow.
“We use every possible technology and bell and whistle to make [the CO2 systems] more efficient,” DeCicco said in a retailer panel discussion at the FMI (Food Industry Association) Energy & Store Development Conference, held in Baltimore September 23–26. He referred to the upcoming installation of Flō technology as well as a geothermal precooling system installed last year at a renovated store in Harrison, New York; the geothermal system employs five 500ft (152m) wells, piped back to a heat exchanger on the return line from an adiabatic gas cooler.
“We try to make each project a little more efficient than the last,” he added.
DeCicco cited the need to cut back on electricity usage due to the “crazy” electric rates in New York. “We install as much solar as we can to reduce usages, even if it’s 20%,” he said.
At the ATMOsphere America conference in 2023 (hosted by NaturalRefrigerants.com publisher ATMOsphere), DeCicco reported that his Larchmont, New York, store, built in 2015 with a transcritical CO2 system, used 7 to 37% less electricity – depending on the month – than a similar-sized store using a traditional HFC (R404A) system.
Another FMI panelist, Chris Braun, Director of Construction and Facilities at Coborn’s, a Minnesota-based grocery chain, noted that transcritical CO2 refrigeration systems “works well for us,” given the chain’s “cold weather” location in the Upper Midwest of the U.S. Tests of CO2 stores compared to those using synthetic refrigerants show that Coborn’s is saving energy with CO2, he said.
But Coborn’s is still working on “figuring out” how to cost-effectively retrofit existing stores to transcritical CO2, Braun added.
“We try to make each project a little more efficient than the last.”
John DeCicco Jr., President and CEO of DeCicco & Sons
