Future compatibility of district heating in urban areas — a case study analysis in the context of integrated spatial and energy planning

Background

District heating is widely used for thermal energy supply and offers a broad range of benefits like the possibility to integrate decentral heat supply technologies or to foster the utilisation of renewable energy sources. Thus, district heating has the potential to gradually contribute to a more sustainable thermal energy supply and to consequently facilitate the energy turn. However, due to specific requirements of this technology, strategic planning is required for the successful implementation of district heating networks. Previous research mainly focuses on either economic, environmental, or technological aspects of district heating. This study therefore aims to execute a comprehensive assessment of district heating systems in the following four sections: (1) integrated spatial and energy planning, (2) costs, (3) resources and (4) environment and climate.

Methods

To this end, the recently developed Eco.District.Heat kit (EDHk) is used to evaluate and rate eight case studies consisting of 14 different urban typologies, while considering the aforementioned sections of interest. The paper applies the EDHk to assess different spatial structures and grid configurations as well as a broad mix of different thermal energy sources.

Results

With regard to integrated spatial and energy planning (section 1), the assessment shows heterogenous ratings whereas the case studies exhibit quite constant positive ratings with regard to costs (2), environment and climate (4). Although a lot of material is used for the construction of networks (i.e. resources, section 3), the question whether or not to dismantle old grids for resource utilisation cannot be answered definitely. According to our results, future development scenarios in the context of climate change and building renovation until 2050 have little influence on the final ratings.

Conclusions

Based on the comprehensive assessment of eight case studies, it can be concluded that district heating systems offer a long-term and sustainable solution of heat supply for different spatial archetypes and types of urban fabrics. Furthermore, the proposed methodology allows users to critically examine planned projects and to detect shortcomings at an early planning stage. The EDHk thus provides a suitable methodology to support strategic decisions in integrated spatial and energy planning.