Evaluating the Efficiency of Fifth-Generation District Heating and Cooling Using Sector-Coupled Co-Simulation

Fifth-generation district heating and cooling (5GDHC) can significantly advance the decarbonization of the heating and cooling sector. It supplies thermal energy at low operating temperatures, which improves efficiency and allows for using low-grade heat sources. This study evaluates the energy efficiency of sector-coupled 5GDHC systems, as such systems rely on heat pumps, they are closely integrated with the power grid. We adopt a co-simulation approach that incorporates a dedicated building simulation tool to capture the dynamic interactions between the 5GDHC network, buildings, and the power grid. For comparison, we define a baseline scenario with air-source heat pumps. The study then quantitatively compares this baseline with two 5GDHC scenarios, one with and one without waste heat. Their performance is evaluated using the system coefficient of performance and exergy efficiency. Results show that the 5GDHC scenario achieves the highest overall energy efficiency. However, adding a waste-heat source can marginally reduce system performance. The findings also indicate that a balanced seasonal demand profile enhances overall efficiency.