• Max-Julian Gerlach
The buildings sector in Germany has missed its greenhouse gas emission reduction target for two years in a row with the majority of the emissions relating to the use of fossil fuels for heating. Therefore, urgent action is required and new support schemes for district and individual heating have been introduced. While DH currently accounts for 14% of the heat demand, other countries have reached a share of more than 60%. This thesis therefore aims to answer the question which role district heating can play for German municipalities larger than 10,000 inhabitants in order to supply heat in an economically feasible way and reach climate neutrality in 2045 in light of the new support scheme BEW while considering the different potentials for renewable and waste heat?

The research design is based on the theories Multi-Level Perspective, which explains the transition of the heating sector and Choice Awareness, which explains how radical technological change towards renewable district heating can be implemented. In combination with the guidelines for municipal heat planning, this also leads to the selection of the methods. Besides data gathering, the heat demand and existence of district heating as well as the potential for renewable and waste heat for urban areas are analysed. This is followed by a cluster analysis and an energy system analysis in order to assess the feasibility of district heating.

The heat demand in urban areas with existing district heating is overall higher compared to areas with potential district heating. Furthermore, the heat demand is expected to decrease by around 35% until 2045, while the district heating distribution capital costs are doubled over the same time. Currently, on average around 90% of the heat demand can be covered by 4th Generation district heating. While waste heat and ambient heat from lakes is only available in less than 25% of urban areas, ambient heat from river and wastewater are the most promising heat sources in addition to solar thermal.

The cluster analysis showed the no optimal number of clusters could be determined based on the selected input variables. Therefore, max and min cluster are derived based on statistical criteria where the max cluster represents a large and a medium-sized urban area with all available renewable and waste heat potentials in urban areas with existing and potential district heating respectively. On the other hand, the min cluster represents a medium-sized and a small urban area with no heat potentials in urban areas with existing and potential district heating respectively.

While district heating is more feasible compared to individual heating for both the max and min cluster currently, it is only more feasible in 2045 for urban areas with existing district heating. On the other hand, establishing new district heating is only feasible in 2045 if sufficient waste heat potentials are available, but otherwise individual heating is more feasible. In general, waste heat is the cheapest heat potential available and otherwise large-scale heat pumps in combination with solar thermal and heat storage are used if available. Furthermore, combined infrastructure planning has the potential to reduce the costs of district heating and make it more feasible than individual heating.

Therefore, it can be concluded that district heating is feasible for urban areas with existing district heating, while the establishment of new district heating towards climate neutrality 2045 is uncertain and depends significantly on the time of investment or combined infrastructure planning.
SpecialisationSustainable Energy Planning and Management
Publication date2 Jun 2023
Number of pages128
External collaboratorBBH Consulting
Lars Dittmar lars.dittmar@bbh-beratung.de
ID: 532689158