How Will We Keep Warm in the Future?

Key takeaways from Denmark’s National District Heating Summit - March 20, 2025

Denmark is internationally recognised for its advanced district heating systems and integrated energy planning. But even in a world leader country, major questions remain:

How will heat be produced in the future? Which technologies and energy sources will lead the way? And how can the sector ensure flexibility, security of supply and climate neutrality in a rapidly changing energy landscape?

These were the questions addressed at the Danish district heating industry’s national summit on March 20, 2025 – a full-day event that gathered experts, utilities, industry leaders and researchers to discuss the path forward. The programme also included a site visit to Silkeborg Utility, offering real-world insights into the future of heat production.

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Green transition: Four key strategies for carbon neutrality

Professor Henrik Lund, Aalborg University, kicked off the event by outlining the strategies required to decarbonise Denmark’s energy sector – with lessons applicable far beyond its borders. According to Lund, four critical levers must be pulled:

• Energy efficiency in buildings (36–40% savings potential)
• Expansion of district heating networks (to cover 63–70% of buildings)
• Better utilisation of surplus heat and geothermal energy
• A diversified heat supply mix, balancing renewables and backup capacity

As electricity consumption is expected to more than double by 2045, smart sector coupling and flexibility are key. District heating, Lund stressed, plays a vital role in integrating variable renewable energy and decarbonising urban heat.

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Biomass, biogas, hydrogen – what fits where?

Presentations and panel discussions revealed diverse views on the role of biomass. Ørsted highlighted climate-friendly biomass with carbon capture as a cost-effective and dispatchable heat source – especially when wind and solar can’t deliver. Others were more cautious, pointing to long-term supply risks and competition with other sectors.

Biogas was presented as a scalable and flexible solution – especially as a replacement for natural gas. With increasing carbon prices under the upcoming EU ETS2, biogas could become a cornerstone of local and regional heat production while also enabling green methanol for the industry.

Green hydrogen is gaining momentum in Denmark, but there was broad agreement that its use should be prioritised for sectors that cannot electrify – such as aviation, shipping, and heavy industry. In heating, hydrogen is considered inefficient compared to electric heat pumps or surplus heat.

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Electricity markets, flexibility and the new normal

Carsten Vittrup from Energinet (Denmark’s TSO) addressed the future of electricity pricing. Variable power production from renewables means we must accept – and even embrace – large price fluctuations throughout the day. In this context, district heating integrated with solar and wind can serve as a local hedge and flexibility enabler.

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Local utilities show the way: Innovation on the ground

Real-life examples from Danish utilities showed that there is no one-size-fits-all solution.

• Silkeborg Utility invests in a diverse technology mix, combining biomass, electric boilers, heat pumps, and surplus heat while balancing cost and security of supply.
• Billund Heating Utility focuses on electrification in close collaboration with local industry.
• District Heating Funen (Odense) is moving towards carbon-negative heating by integrating surplus heat from Meta (Facebook), large-scale heat pumps, and innovative storage solutions.

Their mindset has changed from simply delivering heat to delivering system value.

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Collaboration, consolidation, and digitalisation

In a series of panel discussions, one theme kept recurring: collaboration is essential – both across utilities and sectors. Participants pointed to a growing need for digitalisation, new skills, and stronger coordination, especially in light of cybersecurity (NIS2), energy market volatility, and increasingly complex regulatory landscapes.

At the same time, several participants warned that over-commercialisation and fragmentation could threaten the social and economic foundations of collective district heating – a model that has served Denmark for decades.

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Conclusion: District heating can lead – if empowered

The summit confirmed that district heating is not only relevant in a green future – it is foundational. With its ability to integrate surplus heat, balance electricity systems, and decarbonise urban energy, it stands as one of the most flexible and cost-effective pathways to climate neutrality.

But unlocking its full potential will require:

✅ Smarter regulation

✅ Stronger investment signals

✅ Bold decisions – even when the future is uncertain

✅ And, above all, more cooperation across technologies, sectors, and borders.

Learn more at dbdh.org – your international gateway to climate-friendly district heating solutions, insights, and innovation.