Spotlight on: the Danfoss Smart Store

Andrew Gaved visits a retail concept which promises huge efficiency gains from utilising a whole suite of technologies in an integrated system.

Manufacturer Danfoss has unveiled its new Smart Store, its latest Application Development Center, which is attached to a working convenience store, enabling it to trial a host of energy-efficient technologies.

By applying an integrated portfolio of technologies, including heat pumps, solar PV, heat recovery and efficient CO2 refrigeration, the company believes the Smart Store can save 50% in energy costs over a similar CO2-cooled store and 20-30% over an energy-optimised store.

The 1400 sq m Coop 365 convenience store next to Danfoss’s HQ campus in Nordborg, Denmark, will be monitored with cloud-based remote monitoring and optimisation from the manufacturer’s Alsense platform.

But Danfoss is not confining its ambitions to the store alone – the building is integrated into a district heating system which, thanks to a heat exchange station and, ultimately, battery storage, the company will be able to use to manage energy demand and sell it back to the Grid.

In officially opening the ADC, Danfoss Climate Solutions president Jürgen Fischer said: “We think our technology is at the heart of the energy transition…But it is not all about the technology – it is also about profitability for the customer, so we need to keep that in mind too. We want to help our customers get to net zero and maybe we have to invent some more technologies to get to that, but we believe we can do a lot with what we have and that is what we are demonstrating here.”

He added that the decision of the retailer to build a store in this part of Nordborg had provided an unprecedented opportunity for the manufacturer, not least because it enabled the sharing of investment costs. He said: “I had always dreamed of having a living lab but had not been able to build one.”

The concept of the Smart Store was hailed by Peder Gabrielson of the European Environment Agency, who gave the keynote speech at the launch. He said: “When energy efficiency and low global warming potential (GWP) refrigerants work in tandem, we can vastly cut emissions from heating and cooling. The need to use energy more efficiently and to reduce costs is constantly growing. Innovation like what we see here has a key role to play in finding the best solutions.”

Unparalleled opportunity

The store is managed independently by a joint venture between manufacturer and retailer, which they believe will provide an unparalleled opportunity to optimise the technologies in a ‘real world’ situation, – including all the staff issues that come with it, such as keeping refrigerator doors closed for maximum efficiency.

It is also being operated under an energy as a service (EAAS) model, enabling retailers to access technical facilities with reduced operational expense. The EAAS concept will also enable the customer to operate the latest equipment without the high upfront costs usually associated, Danfoss added.

The store will primarily be powered by its 100 kW solar PV array, but the integration into a district heating loop will enable it to take heat from the site’s data centre. The company forecasts that the heating costs will be cut by 90%, thanks to heat recovery from this and the refrigeration system.

Impressively, it predicts a payback of 1-2 years – or even less – on the CO2 refrigeration system costs, thanks to the heat recovery. The purpose-built Heat Recovery Unit is now in use in 165 supermarkets in Europe.

Another key element of the energy equation Is to use the refrigeration system as a ‘thermal battery’ to store energy from the freezers at low cost times and to switch off refrigeration compressors at high-cost times. Twin hot and cold tanks provide this thermal storage for the store.

Alongside heat recovery, among the other features that will help to cut the energy at Nordborg are:

  • Smart case control: Around 8-12% of energy use can be saved from matching case demand to capacity.
  • Integrating HVAC&R: The company believes that simply by integrating the refrigeration with the cooling, air handling and hot water systems, it can wreak energy savings over the conventional system of separate circuits.
  • Doors on fridges: This is estimated to save up to 32% in energy over open versions.
  • LED lighting: Danfoss notes that while this is low hanging fruit, saving 85% in electricity over incandescent bulbs, LEDs also preserve food for longer as they don’t emit heat.
  • Building design: A green roof, added to rainwater harvesting and a distinctive circular design, all provide additional sustainability credentials.

The ADC features a second CO2 refrigeration pack alongside the pack required for store operation, which will be used for additional trials and concept-testing. The facility also gives Danfoss the opportunity to showcase many of its component products in collaboration with supply chain partners. Thus, for instance, both the standard refrigeration pack in the store and the advanced test pack feature Danfoss pack controllers, compressors, valves and drives.

Jürgen Fischer said that these innovations had the potential to significantly change the way supermarkets use energy. He said: “I believe that by combining online connectivity and digital optimisation we can transform supermarket systems into managed energy systems… Thermal storage is the cheapest method of storage and we need to develop that at mass scale…this is a fantastic opportunity for the industry to focus on hydronic loops and thermal storage to reuse heat.”

The manufacturer intends that the new ADC will be the starting point for discussion with both retailers and the supply chain over optimising energy and decarbonising the sector – supermarkets are estimated to account for 3% of global electricity consumption.

The company said: “The collaborative test environment will empower OEMs, contractors, food retailers and Danfoss engineers to develop new technologies and solutions to enhance energy and operational efficiency for food retail… it will offer the cooling and heating industry the opportunity to access state of the art test facilities and expert support for field testing new components and cloud technologies for both small and large applications.”

Smart Store facts

  • CO2 Refrigeration Pack providing 29 kW Medium Temperature and 13 kW Low Temperature cooling load to 800 sq m sales area
  • Comfort cooling using glycol loop, 20 kW from rooftop chiller and 20 kW from second refrigeration pack
  • Additional heat recovery load provided by a 1 km-long 20 kW ground loop
  • 100 kW of Solar Panels providing 100,000 kWh/yr