Ramboll: Companies can supply 100,000 households with excess heat

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John Ammentorp

Country Market Director for Energy

T: +45 5161 6380

Anna Ekdahl

Manager – Energy Transition

T: 45 51 61 37 41
Companies can supply surplus heat to 100,000 households in Denmark
Excess heat is waste heat from companies’ production. Today, large amounts of heat disappear into thin air, but it is possible to utilise the cheap and climate-friendly heat via the district heating network. From 1 January 2022, the tax on utilising excess heat no longer applies if the company supplying the heat is certified by the Danish Energy Agency. This means that utilising excess heat pays off now more than ever before. 

The report estimates that only 40 percent of the excess heat from companies is currently utilised. This heat originates from relatively few companies.

The possibilities of utilising the excess heat is generally greatest in the large production companies. They often produce large amounts of excess heat with a high temperature, which does not need to be further increased before the heat is distributed into the district heating network.

“Companies looking for an offtake for their excess heat need to reach out to their local district heating plant and other companies with excess heat in the neighbourhood and enter into a collaboration. Companies with excess heat are often located in close vicinity to each other in business areas and by working together to utilise the excess heat, the business model becomes even better with greater benefits for both the company in question and the district heating company,” says Tina Kramer Kristensen, Director of Energy Systems in Ramboll.

There is even more excess heat to be found outside industry, the report points out. Data centres, wastewater treatment plants and waterworks can all supply large amounts of excess heat if they are connected to the district heating network. This is heat with a relatively low temperature, which must be increased through a heat pump before it can be utilised for the heating of households.

If it is to be profitable to utilise the excess heat from, for example, data centres, they must be located close to a district heating network.

“We recommend that the government should establish a taskforce with the goal of ensuring that there is coordination between authorities so that we utilise as much excess heat as possible. In many cases, there is a need for concrete guidance so that companies, district heating companies and municipalities can find their way around the rules,” says Troels Ranis.

Some companies are prepared to give away their excess heat. In this case, it can be necessary to further relax the rules. DI Energy and Ramboll recommend that these companies should be spared of the hassle of becoming certified.

“For small and medium-sized enterprises, energy certification is relatively expensive and administratively cumbersome. If we are to utilise the excess heat from the companies that are willing to give the heat away, it is advantageous to remove the tax and the requirement for certification for them,” says Tina Kramer Kristensen.
Companies can supply surplus heat to 100,000 households in Denmark