Evaluation of interactions between buildings and district heating networks

In the context of district energy systems, changes in a building’s heat demand also affect the energy efficiency of the whole district heating network. We present an integral dynamic model of a district heating network branch with three buildings. By comparing simulations of a reference case and a retrofit scenario we show that reducing the buildings’ heat demands also reduces the mass flow rate in the network branch. We discuss the effects of this mass flow reduction on the energy efficiency of the district heating network and deduce that a district-level system perspective can lead to more comprehensive evaluations of retrofit efforts.