Hotmaps: New Open Source toolbox makes it possible for cities and regions to improve the analysis and planning of their heat supply

October 05, 2020

How is heat demand spread within regions or towns in Europe? Where are the available renewable energy sources to meet this demand? Researchers from Fraunhofer ISI worked on answering these questions in an EU-wide project called Hotmaps, as part of a consortium of research institutions and cities coordinated by the TU Wien. The project team has now published a web-based Open Source toolbox that enables cities, regions and countries in Europe to determine and model their heating and cooling demand, and then develop strategies based on this.

Among other things, the Hotmaps toolbox can plot the heating and cooling demand of EU member states in a GIS software environment, match this with the available renewably produced energy, and develop scenarios to meet this demand in a carbon-neutral way at local, regional and national level. The online tool can be used free of charge under an Open Source license and is ready to use quickly thanks to an extensive data set for all cities and municipalities in Europe.

Objective: To draw attention to unused potentials

In particular, the Fraunhofer ISI contributed its expertise in the field of industrial excess heat to developing the toolbox. This included (i) a database of the excess heat of industrial facilities and (ii) a tool to estimate the industrial excess heat for individual locations. Those involved in the project also developed an instrument to assess the potential of integrating excess heat into district heating networks (iii). This tool can be used, among other things, to estimate the transportation costs for integrating excess heat in district heating networks. The overriding objective is to direct the attention of municipalities, cities and countries towards unused potentials and to help them improve their planning. The toolbox has been successfully tested in six pilot regions in Europe, including Frankfurt am Main.

“We received positive feedback from our pilot areas, such as the Frankfurt Energy Department, that the Hotmaps toolbox provides effective support for regional and municipal heating planning,” says Ali Aydemir from Fraunhofer ISI. “By using the toolbox, municipal energy planners can quickly get an overview of where heat demand is high enough to warrant investments in district heating pipelines, for example. This makes it easier to identify hot spots, which can then be explored in more detail in additional analyses. The toolbox and its default data also provide a systematic framework for strategic heating planning.”


Context: More than half of the energy consumption in Germany is due to supplying heat, but less than20% of this is produced using renewable energies. In order to meet the national climate targets for 2050, therefore, rapid and decisive change is needed. Due to the local nature of heating systems, measures must be taken at local level that consider a multitude of participants. Strategic heating and cooling planning has proven an effective and efficient instrument in this respect and is therefore becoming increasingly important. For example, the amendment of the Climate Change Act in Baden-Wuerttemberg provides for obligatory heat planning for large cities. In the best case, heat planning is supported by the relevant software. Hotmaps meets this need.

The Fraunhofer Institute for Systems and Innovation Research ISI analyzes the origins and impacts of innovations. We research the short- and long-term developments of innovation processes and the impacts of new technologies and services on society. On this basis, we are able to provide our clients from industry, politics and science with recommendations for action and perspectives for key decisions. Our expertise is founded on our scientific competence as well as an interdisciplinary and systemic research approach.