Ambitious climate protection targets require a transition to a highly performant and renewable energy system. The built environment is a key sector for fast emission reduction in many countries. For instance, in the EU, 36% of the emissions are due to buildings, so reaching ambitious climate protection targets will be strongly facilitated by a transition of the building sector. Heat pumps are seen as the future heating system in many scenarios. The IEA Net Zero by 2050 report, for instance, states that 50% of the global heat demand is met by heat pumps by 2045.

Thus, the integration of heat pumps into the energy system on a large scale is a future challenge, but also an opportunity to derive a highly performant and CO2-free energy system. Positive energy districts are an ambitious objective to pave the way for the urban energy transition. Heat pumps can effectively couple different thermal and electric loads in districts at high performance. Thus, using synergies by system integration in districts can even increase the heat pump performance, while the coupling of electric and thermal loads also provides energy flexibility to the connected grids.


The overall objective of the Annex is to evaluate the role of heat pumps in positive energy neighborhoods/districts. Efficiency potentials of the electric and thermal energy of neighborhoods/districts that can be unlocked with the use of heat pumps and are evaluated in order to reach a positive energy balance. This refers both to heat upgrade of waste heat and to simultaneous generation of different building services like space heating, DHW and space cooling/dehumidification and higher self-consumption of on-site electricity production. As starting point heat pumps in individual buildings are considered, and successively generic concepts on neighborhood level will be evaluated taking into account limitations on the individual building level. Thereby, the role of heat pumps for positive energy neighborhoods shall be defined and a road-map to positive energy district with heat pumps shall be developed.

Contact Person

Prof. Carsten Wemhöner,

Participating Countries

Austria, Germany, Italy, Japan, Switzerland, the USA


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