Simulation and Measurement Results of a Smart District with Connected Heat Pumps, PV and CHP as a Model Project for Decarbonizing Existing Multifamily Buildings

Heat pumps are expected to play a central role in decarbonizing the building sector but face challenges in existing multifamily buildings. A smart district energy system connects heat pumps, PV modules and combined heat and power units to achieve an energy- and cost-efficient operation. Dynamic simulations indicate that CO2 emissions can be reduced by 52 % compared to the current energy system, without energetic refurbishment of the buildings. A further CO2 reduction could be achieved by a larger share of heat pumps, however at the cost of a lower economic profitability. Measurement results from the first heating period are presented and discussed. The dual source heat pump system achieves a coefficient of performance of 3.1, after lowering the heating curve and optimizing a peak load mixing valve. On district level, a high level of electrical autarky (88 %) and self-sufficiency (81%) was achieved in January 2022 and electricity for the heat pumps was fully supplied by the CHP and PV systems.