Measurement Data-Based Estimation of the Suitability of Existing Properties for the Operation of x to Water Heat Pumps Using a Seed of 100 Multi-Family Houses and Different Power Shifting Approaches

The German government’s ambitious goal of achieving CO 2 neutrality by 2045 has prompted a focus on improving building insulation as a vital step toward energy efficiency. However, in this process, existing radiators and boilers are often left unchanged. Moreover, during the construction of buildings, heating systems are often designed with excess capacity to ensure there is no risk of insufficient heat supply during operation. This research presents various approaches to reduce the required radiator supply temperature, utilizing data from a study conducted in 100 multifamily buildings. The approaches encompass reducing the heat reserve, shifting the heat output, optimizing radiator utilization, and conducting heat demand analysis. The findings reveal that in pre-existing buildings equipped with radiators, it is possible to significantly lower supply temperatures without affecting the indoor temperature. Applied on the seed, reducing the heat reserve could reduce the median temperature by 18.5 K, thus curtailed by the most utilized radiator in the median to 7 K. Furthermore, the heat demand analysis showed that the consumption could decrease in the median by 13%, the peaks in median even by 29%. While each approach is analyzed individually, their combined implementation has the potential to considerably enhance the efficiency of water-to-water heat pumps, thanks to the reduced requirement for high supply temperatures.