Skip to content


Heat pumps




Warming up Copenhagen by harnessing heat from seawater and wastewater

In a move to reduce reliance on biomass and fossil fuels, the Greater Copenhagen Utility, HOFOR, has set plans to install new heat pumps that utilize heat from seawater and wastewater to warm up the residents of the Danish capital.


HOFOR, Greater Copenhagen Utility, is the largest utility company in Denmark and it supplies about 1 million Danes with district heating. The utility company is owned by 8 municipalities and the City of Copenhagen owns a 73% share of the company.

Discover HOFOR

Today, district heating covers 98% of the heating demand in Copenhagen. In the future, Danish homes will be heated up by using even more green energy, for example by utilising seawater and wastewater through heat pumps.

The Greater Copenhagen Utility, HOFOR, has proposed plans to increase Copenhagen’s residential heating landscape with collective electrically powered heat pumps in the forthcoming years. By 2033, up to 10 strategically positioned heat pumps will dot the Copenhagen landscape, collectively amounting to a production of up to 300 MV of heat. These heat pumps harness green power sourced from wind turbines while optimising the utilisation of temperature gradients found in surplus heat, seawater, and wastewater.

Related news: New plans to expand the danish district heating network 

District heating: A Swiss army knife in transforming future energy systems

Explore our publication and learn how Denmark’s district heating system are used as a key tool in transforming the future energy system, paving the way towards reaching ambitious climate goals.

Discover the publication

En route to creating a carbon-neutral capital

Copenhagen has set aims to become the world’s first carbon-neutral capital. Using green energy sources for district heating is a cornerstone in reaching these ambitions.

Prior to establishing up to 10 new heat pumps, HOFOR has dedicated several years to accumulating valuable knowledge and ensuring the integration of advanced technology through three smaller heat pump projects with a combined capacity of 10 MW.

Related news: One-third of Copenhagen’s hotel rooms are now cooled with seawater

However, the coming project represents a shift in scale. Notably, two of these groundbreaking heat pumps, located at Nordhavn and the Lynetten treatment plant, will jointly possess a capacity of up to 200 MW. The estimated cost for their construction is approximately EUR 260 million and the planning of the first of these two very large heat pumps will start already in 2024.

“Copenhageners can look forward to their heat supply becoming greener. Fossil fuels, which we use when it is coldest, will take up less space in the city’s heat supply as the heat pumps are phased in, and the security of supply, which is already high, will become even higher. In addition to this, and probably just as importantly, the heat pumps will make a significant contribution to Copenhagen’s plans to become climate positive in 2035,” Gorm Elikofer, Energy Director at HOFOR.

Other derivative effects of the large heat pumps being established are diminishing shares of biomass in the city’s heat supply as well as more energy flexibility.

“When heat is electrified in this manner, it introduces increased flexibility into the entire energy system. We can harness green power when it’s abundant, and power down when costs become expensive,” Gorm Elikofer, Energy Director at HOFOR.

Information: District heating in Copenhagen

  • Approximately 10 new heat pumps are poised for installation in various locations across Copenhagen.
  • The two largest facilities, situated at Yderste Nordhavn and Renseanlæg Lynetten, will have a combined production capacity of 170-200 MW, equating to around 18% of Copenhagen’s district heating consumption.
  • Three medium-sized heat pump projects, placed at Kløvermarken, Kranparken, and Bådehavnsgade, will collaboratively provide an additional 70 MW of heating capacity.
  • Collectively, these new heat pumps will deliver 300 MW of heat.
  • The investment for the  10 heat pumps accounts for approximately EUR 403m (DKK 3b).
  • The pumps will play a pivotal role in replacing a portion of the biomass currently utilised in Copenhagen Municipality.
  • Over time, these large-scale heat pumps will gradually supplant the need for plants where HOFOR currently relies on gas and oil for heat production.

You should consider reading

District energy
District heating
Heat pumps


Resource efficient production


New white paper on transforming global food systems for a more sustainable and resilient future

8 December 2023
Launched at COP28, a new white paper by State of Green examines pathways toward a resilient, resource-efficient and decarbonised agrifood system.


Climate COP


COP28: New global alliance to advance negative emissions

11 December 2023
It is not enough for all countries to aim for climate neutrality; some must go beyond and become climate-negative. Aimed at achieving this after 2045, Denmark has launched the GONE alliance with like-minded countries.




Green hydrogen is Danish hydrogen

19 September 2023
Get a full overview on how hydrogen can produce green fuels for transport and industry, create value for electricity supply and the electricity grid, and deliver heat for district heating - provided the input is green energy.




Green hydrogen derivatives for deep decarbonisation

19 September 2023
Hydrogen is an important enabler for the production of hydrogen derivatives, such as e-methanol, e-ammonia, and e-kerosene, which can be used in industry and transport.