Starting with on overview of the IEA HPT Annex 61, the state of the art of positive energy districts has been summarized in term of definitions, applied certification schemes and the role of heat pumps. For the Swiss 2000-W-site label, for instance, which comprise 50 districts in planning, in operation or in transition, heat pumps are the most applied heating and cooling technology.
Furthermore, an overview of the Swiss contribution dedicated to the analysis and optimization of a retrofitted district, which will be further developed until 2035 to 1,000 flats and 1,000 office workplaces. The district is equipped with an entirely renewable heating and cooling system by four centralized ammonia heat pumps of 4 MW capacity in the final development stage. 192 ground probes and river water serve as source for space heating and cooling, which comprise also operation modes of ground-coupled freecooling and regeneration of the probes. The distruct is certified according to the Swiss 2000-W-site label and has been award with the Watt d’Or of the Swiss Federal Office of Energy in 2024.
The conference is held in German/French with simultaneous translation and contributions will be published as proceedings.