New York-based food retailer DeCicco & Sons has determined that its Larchmont store, built in 2015 with a transcritical CO2 (R744) system, uses from 7 to 37% less electricity – depending on the month – than a similar-sized store using a traditional HFC (R404A) system.
John DeCicco Jr., President and CEO of the 10-store chain located in the suburbs just north of New York City, presented the information of this finding during the end users panel discussion at the ATMOsphere America Summit 2023, held June 12–13 in Washington, D.C.
The Larchmont store was the sixth outlet in the retail chain and the first to use CO2 refrigeration, earning DeCicco a spot on the front cover of Accelerate America magazine as one of the few independent stores in the U.S. to implement such a system.
“We’ve done every [new] store since that store in 2015 the same way,” said DeCicco.
He citied the energy savings from reduced electrical use and demand at the Larchmont store as US$77,834 (€71,286) annually. The largest energy savings, roughly US$12,000 (€10,990), were seen in September.
Besides building new stores with CO2 systems, the company has rolled out retrofits, replacing traditional R404A with transcritical CO2 systems. All stores use adiabatic gas coolers for precooling as needed during high ambient temperatures. So far, seven of the company’s ten stores use CO2, with an eighth on the way. “We hope to convert all of our stores to CO2 in the next three to five years,” said DeCicco.
DeCicco & Sons’ other CO2 stores also use less energy than a store with an R404A system, he added.
The company recently renovated its Harrison store, adding 5,000ft2 (465m2) of space and switching it to a transcritical CO2 system using an adiabatic gas cooler with geothermal precooling from five 500ft (152m) wells, with each well looped back into a manifold.
Aiming to further reduce energy use on days with temperatures above 85–90°F (29.4–32.2°C), the wells pipe back to a heat exchanger on the return line from the adiabatic gas coolers. By adding the geothermal wells, DeCicco hopes demand reduction on the hottest days reaches US$30–50 (€.50–45.80) per kilowatt.
The system was filled with glycol a week before the ATMOsphere summit. As a result of the timing, DeCicco was unable to share operational data. “I am very anxious to see how it performs,” he added.
“If I can avoid that last compressor going on and keep the rack from going transcritical, I think [the wells] will be able to pay for themselves in five years,” DeCicco said, with each well costing $9,000 (€8,240). “I am comfortable with a three-to-five-year payback on any measure we put in place,” he added.
Increasing efficiency
“The refrigeration system is the heart of the supermarket, and it is definitely the biggest energy guzzler in the entire store,” DeCicco said, adding that 60% of the chain’s revenue comes from its perishable departments. “It’s how all the systems work together that makes the biggest difference.”
The 24,000ft2 (2,230m2) Larchmont store uses a Hillphoenix transcritical CO2 system with 1,000lbs (454kg) of refrigerant, providing 919,000BTU (76.6TR/269.3kW) of medium-temperature and 103,000BTU (8.6TR/30.3kW) of low-temperature refrigeration capacity. Besides reclaiming heat waste, the system utilizes a BAC adiabatic hybrid gas cooler to increase system efficiency during high ambient temperatures.
The store store also features advanced, energy-efficient LED lighting and motion sensors to reduce electricity usage during low occupancy, says DeCicco & Sons on its website, with solar panels installed on the roof generating approximately 215kWh of energy.
Additional energy-efficient measures used at the store include variable frequency drives (VFD) on lead compressors, humidity-controlled anti-sweat heaters, a demand-based ventilation system with makeup air and exhaust, and a Carrier weather master HVAC package that “strictly” controls store humidity at 55%.
“We found all these things together with night curtains and case controllers save electricity in a big way with transcritical CO2,” DeCicco said.
In addition, the company’s Somers store reclaims heat from the refrigeration system to provide radiant floor heating. Using 2022 data, DeCicco compared the Somers store to another with equal rack horsepower, heat reclaim and cooking energy usage. Both stores used hot water and makeup-air reclaim.
The Somers store used 0.57gal of propane/ft2 (23.9l/m2) for comfort heating, while the similar store used 1.41 gallons/ ft2 (59.2l/m2). Providing radiant floor heating from reclaimed heat resulted in a 60% propane savings, with most of that savings coming in the colder months, DeCicco said.
John, Joe and Frank DeCicco started DeCicco & Sons with a small storefront in the Bronx in 1973.
“We hope to convert all of our stores to CO2 in the next three to five years.”
John DeCicco Jr., President and CEO of DeCicco & Sons
