With the establishment of a 10.2 MW heat pump, the Danish utility company Envafors will be able to further optimize their green district heating supply and ensure sufficient heat capacity to provide both current and future district heating customers with green district heating.


Client:       Envafors
Location:    Halsskov
Status:    Under construction
Technology:    Heat pump system
Capacity:    10.2 MW
Contract type:    EPC

Optimized efficiency and flexibility

The order for Envafors is a turnkey contract consisting of a 10.2 MW air-to-water heat pump with associated pipes and exchangers. The contract, likewise, includes integration with the district heating plant's existing solar heating system and biomass boiler. The heat pump system, which is tailored to fit the district heating plant’s specific energy needs and existing system, uses outdoor air as the source for heat production. The 10.2 MW heat pump constitutes the third renewable energy technology that Envafors is adding to their heat supply and will boost the efficiency of the district heating plant's existing solar heating system and biomass boiler.

Value-adding synergies

During months with less sunlight, the heat pump optimizes the return temperature within the solar heating system allowing the panels to absorb more heat from the sun. This process increases the overall efficiency of the system. Likewise, the energy from the solar system improves the efficiency of the heat pump during those periods, where it has the greatest value for the overall efficiency.

By integrating multiple green technologies, Envafors can adapt the operation of their facilities according to the existing conditions leading to a more efficient and flexible heat supply. Envafors can, likewise, utilize the energy from PV panels and wind turbines for their district heating production during times when electricity market price is low.


  • Design and delivery of heat pump system, piping and civil works
  • Ammonia circuit design
  • Mechanical and electrical installation
  • P&I diagrams and control system
  • Setup of different operational scenarios
  • 3D model
  • Strength and flex calculations
  • Heat balance calculations
  • Dimensioning of the internal heat exchangers’ energy conversion
  • Documentation
  • Supervision of installation and commissioning
  • Legalization of the plant


Andreas Zourellis
VP Sales - International
District heating / industrial solar technologies
Phone: +45 50 30 00 25 
E-mail: azo@aalborgcsp.com