IEA HPT Annex 61 – Heat Pumps in Positive Energy Districts

The building sector plays a key role in reducing CO2 emissions and achieving climate protection goals. Districts offer the potential for further efficiency improvements through coordinated solutions for different building uses and load patterns, which can create synergies on both the electrical and thermal sides. The overarching goal of Annex 61 is to evaluate the role of heat pumps (HP) in Positive Energy Districts (PEDs). Specifically, it aims to highlight the efficiency potentials of districts that can be unlocked by using HPs to achieve a positive energy balance.

Annex 61 builds on the work of Annex 49, which focused on the design and integration of HPs in nearly Zero Energy Buildings (nZEBs). While HPs, when combined with on-site renewable energy generation, demonstrate high efficiency, achieving a positive energy balance in larger buildings or building complexes remains a challenge. Potential solutions may arise from the combination of old and new buildings, for which strategies will be developed in Annex 61.

In PEDs, buildings become net energy producers and thus active parts of the energy system. At the district level, HPs are a key technology for sector coupling, linking heating and cooling needs with electricity generation and the integration of renewable energy sources.

Multiple stakeholders are involved in the development of new concepts for PEDs. Manufacturers must further develop components and system solutions for integration into individual buildings, building groups, and districts. Policymakers require insights into how the energy transition can be implemented at the district level, both for newly constructed and existing districts.