Worldwide, there is a governmental focus on using energy more efficiently and increasing the use of renewable energy, which will lead to a lower dependence of fossil fuels and a reduction of greenhouse gas emissions. Goal 7 for affordable and clean energy of the United Nations has the following subgoals;

  • by 2030 to substantially increase the share of renewable energy in the global energy mix.
  • by 2030 to double the global rate of improvement in energy efficiency.
  • by 2030 to enhance international cooperation to facilitate access to clean energy research and technology, including renewable energy, energy efficiency, as well as advanced and cleaner fossil-fuel technology, and to promote the investment in energy infrastructure and clean energy technology.

The objectives of the IEA HPT Technology collaboration programme is to support the energy security and to demonstrate applications in existing and new energy systems and buildings. Another objective is new cross-cutting, affordable solutions for heating and cooling, where heat pumping technology is a key element through collaboration with other TCP’s, enabling energy savings, flexibility, and responsiveness in energy systems.
IEA HPT Annex 47, which ended in March 2019, focused on existing solutions and technology for heat pumps in district heating grids. This annex showed that up to 50% of heating demand in Europe could be covered by district heating and heat pumps can cover up to 25 % of the energy supply to the district heating grid. This means that the potential for heat pumps is large. Annex 47 showed that heat pumps can be integrated in different ways in the DH grid which means that the losses can be reduced, and the efficiency can be improved.

Annex 47 was joined by Denmark and Netherlands. As the interest in heat pumps in DHC has increased since the start of the Annex, is it expected that more countries are joining this new Annex. From IEA DHC, especially the German partners have shown an interest.

This new Annex will focus more on coming technologies and the possibilities of heat pumps to increase the flexibility in energy systems with different sources such as PV, wind-power, and biomass and where end users can be consumer or prosumer or both (Multi-Vector). Heat pumps in DH systems provide many benefits, since they enable the possibility of running DH systems at lower temperatures, which increases the possibilities of using waste heat. Thus, the grid can run more efficiently as the heat losses can be reduced.

The implementation of District Heating and Cooling (DHC) systems and heat pumps in these systems, is a solution to increase the overall energy efficiency in the public society and to minimize the use of fossil fuels. The implementation of heat pumps in DHC systems is a solution to use waste heat and ambient heat as well as a way to increase the share of renewable energy in DHC systems and in the entire energy system.


This Annex focus on the implementation of heat pumps in district heating and cooling systems, describe possible solutions and barriers for heat pumps on these markets. Creation of the possible flexibility in the thermal network and electrical grid, is a main part of the annex.
The possibilities of increasing a larger share of renewable energy and excess heat as well as reduce the CO2 emission in the used heating systems by using heat pumps will be a focus area of the Annex. In addition, minimizing the system losses by using heat pumps will also be an objective as will the reduction of CO2 emissions.


Particularly, the following issues will be elaborated:

a: Show the potential of heat pumps in district heating and cooling systems (Task 1)
b: Describe demonstration, research, and development projects where flexibility is created by the implementation of heat pumps (Task 2)
c: Present and describe concepts where heat pumps are implemented in DHC networks (Task 3)
d: Describe the kind of flexibility and the potential created by heat pumps in DHC networks and to the electrical grid (Task 4)
e: Identify and present business models with heat pumps in DHC networks and in different electrical markets (Task 5)
f: Describe socio economical barriers and opportunities (Task 5)
g: Disseminate the information gathered in the Annex (Task 6)

Aim of the Annex:

The results of this study are aimed at the ExCo for the HPT TCP, for national policy makers, and decision makers of DHC systems, planers and operators of DHC systems as well as manufacturers of large heat pumps. The results will provide an overview of the possibilities and barriers regarding the implementation of heat pumps in district heating and cooling systems.