Evaluation of the temperature regimes of multi-level thermal networks in urban areas through exergy analysis

The overall objective of this study is to explore the potentials of district heating systems (DHS) operating on more than two high temperature levels. This characteristic allows integrating decentralized and renewable thermal energy sources. It also enables the network to minimize inefficiencies caused by mismatches between supply and demand exergy levels. This paper studies the effects of better suited exergy levels for DHS with two, three and four supply temperature levels. It is shown that having more than two temperature levels is in many cases advantageous both exergetically and economically.