Surplus heat from supermarket cooling can be recycled as district heating

26. July 2021

With the climate agreement, it has become possible to direct surplus heat from supermarkets directly into the district heating network. Now the innovation project shows that it is also economically viable. This will enable the excess heat from 2,700 Danish supermarkets’ refrigeration systems to be revalued as district heating in the future.

It takes a lot of energy to keep the milk cold and the peas frozen in the supermarket’s refrigerated ice. The cooling counter develops heat as a by-product, and that heat now gets value.

The proposal for a new climate agreement has opened the way for supermarkets to use heat production from the cooling system for internal heating and even sell the excess heat to the local district heating company. There is energy efficiency, climate targets and economics in this.

Trade associations and projects have demonstrated the potential of using supermarket surplus heat as an energy resource, most recently in Energy Cluster Denmark’s innovation project Super Supermarkets. With the climate agreement, taxes in this area will be changed to make it profitable for supermarkets to recycle heat.

Kim Behnke, Head of Development at Danish District Heating, is pleased that Danish households can now be supplied with heat directly from their local supermarket

“This means that we can utilize good surplus heat, which would otherwise be wasted and at the same time make supermarkets active players in the process of reaching 70 per cent. CO2 reduction by 2030, ” he says.

Better utilization

It is an essential prerequisite for the 2030 target that we manage to make the most of our common energy resources. That is precisely why Torben Funder-Kristensen, Head of Public and Industry Affairs at Danfoss Cooling Segment, finds the utilization of surplus heat extremely interesting:

“Achieving the 2030 target requires a massive effort in the form of a combination of solutions for e.g., conversion of electricity generation, strong electrification in heating and cooling supply, expansion of renewable energy and as the example of Super Supermarkets has shown: A better use of untapped potentials,” says Torben Funder-Kristensen.

The Super Supermarkets project has focused on an optimised and standardised use of recycled heat from supermarket cooling systems for both internal use and integration into the district heating network.

“The Super Supermarkets project is a strong example of the sector coupling that is an important prerequisite for moving us the last step towards our common 2030 goal,” says CEO Glenda Napier, Energy Cluster Denmark: “We must consider energy as one common, connected system that is mutually dependent and complementary. When you use the heat of the cooling machines in the district heating system, a by-product that has already been paid becomes valuable and climate friendly,” she says.


Behind the Super Supermarkets innovation project are Danfoss, Dansk District Heating, COOP, The Danish Technological Institute and the Danish District Heating Project Company as well as AK Centralen. They monitor all installations and ensure temperature quality 24 hours a day in COOP stores.