On June 29, Danish component manufacturer Danfoss announced the opening of a new public retail “smart store” near its headquarters in Nordborg, Denmark, designed for net-zero operation and built using off-the-shelf technology, including a CO2 (R744) system, to demonstrate that the technology for sustainable food retail is already available.

“We wanted to show what’s possible today with today’s technology in a way that would relate to building owners and end users and be an inspiration for the industry,” said Dean Groff, Food Retail Service Contracts Manager at Danfoss, in a refrigeration case study presented at the ATMOsphere America Summit 2023, held June 12–13 in Washington, D.C.

“It’s not a science project,” Groff added. “Everything that goes into this store you can get in North America.”

“For the first time, all of Danfoss’ most cutting-edge technology and energy-efficient food retail solutions are being brought together into one retail site,” said Jürgen Fischer, President of Danfoss Climate Solutions, in a press release. 

In addition to the roughly 8,751ft2 (813m2) of sales area, the facility also houses an application development center (ADC) for testing energy-efficient technologies, which will be open to industry visitors this coming September. “We also wanted a location where we could advance technology, test it out and prove it to move things further along the development stage,” Groff said.

The store operates with a CO2 refrigeration system, using Danfoss’s ejector technology and a CO2 adaptive liquid management system to “give it one of the most efficient CO2 systems in the industry,” Groff said. The system has a 30kW (8.5TR) medium-temperature and 13kW (3.7TR) low-temperature refrigeration capacity, with electricity supplied primarily from 100kW solar panels on the building’s roof.

Waste heat recovered from the refrigeration system using Danfoss’s heat recovery unit – which was one of three innovations short listed for the North America ATMO 2023 Innovation of the Year Award – supplies the store’s comfort heating and domestic hot water; excess heat is diverted to the town’s district heating network. Danfoss expects the heat reclaim to reduce the supermarket’s heating costs by 90%.

During peak loads in high ambient temperatures, the system is supported by a ground source heat pump, an adiabatic gas cooler, the ejector and a CO2 chiller, with all systems connected and talking through Danfoss’s Alsense digital monitoring platform. Green energy from a geothermal system, wind and biofuels supports the store as needed.

“We can see everything is talking to everything, and it’s in harmony,” Groff said, “meaning we are using the energy we have in the best efficient manner.”

Danfoss expects the store to be 50% more energy efficient than the first generation of CO2 refrigeration systems that do not employ energy efficiency solutions and “20 to 30% more efficient than an equivalent local store fitted with multiple energy efficiency solutions.”

“On paper, the store looks net-zero, but we have to prove it out,” Groff said in his presentation.

Addressing global megatrends

To pave the way for a 21st-century supermarket, global megatrends such as digitalization, electrification, urbanization, climate change and food supply “are all things that this store touches on as we go forward,” Groff said.

The store addresses climate change with natural refrigerants CO2 and propane (R290), as well as gas-leak detection and monitoring. In addition, “we are managing the flow of energy to and from the store into the different loads to maximize the use of that energy,” he noted.

The Alsense monitoring platform provides live data to reduce food waste. “In addition, we are going as far back in the cold chain as we can to monitor the food supply,” Groff said. “With today’s technology, we can predict food loss and guarantee food safety.”

An electric vehicle charging station runs off the store’s solar panels, and excess energy is sent to district heating. “Stores can deliver more energy than they consume and with net-zero emissions,” Groff said.

The store also features a “mega pergola” structure surrounding the building. A micro-environment for biodiversity is in the works with plans to plant different native grasses on a green roof.

“This supermarket is purpose-built for the world ahead of us, a world of more urbanization, larger populations, greater energy demands, a growing need for cooling, and efficient food storage,” Fischer said. “Building a climate-friendly and super-efficient facility using world-class heating and cooling technology is possible.”

At the end of his presentation, Groff invited anyone in North America interested in net-zero to talk to Danfoss. “Let’s show them what we can do here in North America because we know what we did in Europe. We can do it here.”

Established in 1933, Danfoss’s corporate headquarters are located next to the new Denmark “smart store.” The company’s three business segments operate 97 factories in more than 20 countries to provide “innovative and energy-efficient” heating and cooling solutions.

“For the first time, all of Danfoss’ most cutting-edge technology and energy-efficient food retail solutions are being brought together into one retail site.”

Jürgen Fischer, President of Danfoss Climate Solutions