With climate change and the pressure for lower environmental impact, supermarkets are rapidly investing in green energy transition.

The new trend – for-filling heating demand from supermarkets’ own cooling display cases. By installing Danfoss heat recovery units, supermarkets could halve its CO2 footprint in five years.

Imagine if this was done in all supermarkets in the world.

Keeping food fresh forces electricity meters to run fast in a supermarket. Currently, up to 40 percent of the electricity consumption in any given supermarket is used for cooling. However, Danfoss has cracked the code to considerable energy savings by reusing excess heat that would otherwise be wasted.

Excess heat from the cooling display cases and freezers is harvested and heats up the store during winter and cold days; and heats up domestic hot water. Furthermore, the supermarket’s surplus heat could be sent out to warm up office space, warehouses, etc.

This heat recovery solution from Danfoss ensures efficient recovery of the heat from the refrigeration system, and there is hardly any wasted heat. The system can recycle up to 95 percent of the excess heat. This energy transition methodology has proven great success in harvesting savings in supermarkets across the world already.

Some stores have shown savings of around 70 percent on heating costs and about 40 percent on electricity. Not only has this Danfoss Climate Solutions technology shown a reduction in energy costs, but also a huge reduction in carbon footprint by approximately half, covering electricity, water, and heating.

Each year, 100 000 supermarkets are installed or retrofitted all over the world.

There are huge benefits for supermarkets when installing heat recovery technology in terms of saving potential and reduced carbon footprint. The bigger the store, the shorter the payback time with an average of only two years. It’s the cheapest heat any store can get.

Vapor compression systems contain a wealth of opportunities which are among the cheapest and easiest to implement into an emerging smart flexible energy system.

The broader vision for Danfoss is to always have heat recovery on CO2 refrigeration units, and CO2 units are already widespread throughout the world and Danfoss has new initiatives in pipeline, including solutions for locations without a district heating grid. The Danfoss heat recovery solution is a complete unit and is one of many innovations created and yet to come.

Utilisation of excess heat from CO2 refrigeration plants.

The unit prioritises heating of own plant before any sales to e.g. district heating suppliers. In order to balance different usage patterns (temperatures and heating requirements) on the heating side and the production of excess heat on the cooling side, the unit has been designed as a buffer charging circuit. This results in very stable and uniform charging, also ensuring a long service life for the CO2 heat exchanger. The flow temperature from the HRU unit is controlled by the building requirements (heating, hot water or ventilation), either via signals from other ECLs or via Modbus from an existing SCADA system. In the event of possible sale of excess heat to the district heating supplier or other buyers, this can be managed in such a way that a constant temperature is supplied to these buyers. The HRU unit can send a reference signal to the cooling plant indicating how much heat can be accumulated. A safety function has been embedded to protect against boiling over on the water side.