Modeling and Integration of a Reversible Multi-Circuit Heat Pump for Flexible Operation in Thermal Source Networks
Reversible heat pumps (HPs) capable of providing simultaneous heating and cooling are well known at component level, but their role within Thermal Source Networks (TSNs) is still insufficiently explored with fast, system-level simulation models. This paper presents what we believe to be the first implementation of a modular, reversible multi-circuit heat pump model explicitly designed for integration into thermal source network (TSN) simulations with annual horizons. A reversible multi-circuit HP model is developed for a representative building sub-station at incampus in Ingolstadt, Germany. The MATLAB/Simscape model represents three hydraulic circuits (TSN, building heating, building cooling) and five active operating modes plus standby, using a quasi-steady Carnot-based formulation that is lightweight enough for year-long dynamic simulations. The sub-station is embedded in a simplified TSN boundary model and driven by hourly heating and cooling demand profiles. Annual results show that the reversible HP supplies about 93% of the building’s 223 MWh heating demand and 93% of its 244 MWh cooling demand, with auxiliary district heating and district cooling covering the remaining peaks. During dual operating modes, internal heat recovery from the cooling to the heating circuit contributes around 100 MWh, i.e. almost half of the annual heating demand, substantially reducing extraction from the TSN. A comparison with a reference concept using a separate heating HP and chiller indicates that the reversible multi-circuit configuration can reduce TSN heating/cooling extraction by more than half while keeping total compressor electricity almost same. The model therefore provides a practical tool for assessing buildingsubstation design and control strategies in TSNs with simultaneous heating and cooling demands.