Is the Danish model of district heating transferable to Germany? From Hamburg to the World: EEHH heat excursion to south Denmark

Denmark is a European pioneer of the heating transition. Seeking to learn from our neighbouring country, the Renewable Energy Hamburg Cluster Agency (Jingkai Shi, International Cooperation Renewable Energies and Felix Fresen, Project Management Sector Coupling) organised a technical excursion to southern Denmark from 20–21 May 2025 in cooperation with the Royal Danish Consulate General in Hamburg and the Danish Board of District Heating. Included in the delegation were 12 representatives, from organisations such as the Hamburg Department of Environment, Climate, Energy and Agriculture, engineering service providers and universities.

Clear policy direction

Decarbonising the heat supply is crucial to achieving Germany's climate targets. Around 40% of carbon emissions in Germany are attributable to the heating sector. Municipal heating planning is regarded as a mainstay of the heating transition; but heating is predominantly provided by gas at present.

By comparison, Denmark is far ahead of Germany in the heating transition. The oil crisis in the 1970s had an immense impact on Danish economic and energy policy. The Danish government has focussed on alternative energy sources and the expansion of district heating to reduce dependence on fossil fuels. As early as 1979, the heat supply network was adopted in Denmark to make heat planning mandatory for all cities. Fossil-fuelled heating systems have been banned in new buildings since 2013 and in existing buildings since 2016. Around 70% of Danish households are now supplied with district heating. (For comparison: the share of heat supply in Germany is around 15%).

The Denmark Can Do More II reform programme was established in response to the energy crisis resulting from the war in Ukraine in 2022 and now defines the expansion of the district heating supply as one of the central goals of Denmark's climate and energy policy. It stipulates that local authorities must identify areas in their heating plans that can be converted to district heating or connected to district heating networks.

Integration of varied technical solutions

Biomass, heat pumps and waste heat: the Danish district heating system has a broad technological foundation, in which the use of Power-to-X technologies plays an important role. This means that it is not only renewable energies such as wind power and solar thermal energy that are fed into the grid to generate heat, but also industrial waste heat. Denmark leads the world in the promotion of large solar thermal installations that are integrated into district heating systems. At present, biomass accounts for 25% of heat generation. It will fall to around a third going forward, and the supply gap will be gradually filled by industrial waste heat and heat pumps.

Cooperative district heating for the common good

Visiting Sønderborg, Egtved, Horsens and Vojens, the Renewable Energy Hamburg delegation was particularly impressed by the distinctly collaborative culture and how the heating transition is organised in the form of cooperatives. Around 85% of district heating networks in Denmark are operated by cooperatives. District heating operators are not allowed to make a profit, but must cover their costs. Any surpluses either flow back to consumers in the form of lower heating prices or are distributed as dividends. The district heating operators belong to the consumers themselves. They buy the co-operative shares and are therefore collective owners.

And it is not only in the field of district heating that the Danes are ahead of the game. The Renewable Energy Hamburg delegation learnt about the local climate initiative Project Zero in Sønderborg. The municipality of Sønderborg wants to become carbon-neutral by 2029. 80% of the project has already been completed and the net zero target will be achieved on time. Efficiency and reducing electricity consumption were the top priorities here, and carbon emissions were already cut by two thirds between 2007 and 2023. One third of this is attributable to energy efficiency measures. Among the key findings here was that the success of the project is rooted in cross-sectoral collaboration and strong communication with citizens and stakeholders.

Conclusion

There is little doubt that the Danish heating concept cannot be transferred to Germany without direct adaptation. The ongoing political and social consensus on climate neutrality and pragmatic cooperation between stakeholders are key to the success of the Danish heating transition, which we could use more than ever in accelerating decarbonisation in Germany’s own heating sector.

The immense benefits of cooperatives mean that district heating networks can be operated in Denmark even in rural areas with a relatively low heat density, which would be unprofitable in Germany, although the localities are comparable to those in Schleswig-Holstein or Lower Saxony.

Whether it is financial incentives for a low return temperature in the heating network or the organisation of district heating by cooperatives – the impressions from the trip will linger with us and the delegation members for a long time to come.

The Renewable Energy Hamburg Cluster Agency would like to thank its Danish partners for the excellent cooperation and looks forward to other joint activities.