An evaluation of the Hotmaps toolbox for national strategic heat planning

This paper assesses the Hotmaps tool design and its properties for application in national strategic heat planning. As part of this evaluation, the tool design is compared with the EnergyPLAN tool which has been applied for the Heat Roadmap Europe studies, among others. The purpose of this comparison is to achieve a better understanding of both tools and achieve a better understanding of the role of Hotmaps tools in national strategic heat planning processes.
Included in the process is two basic functionalities of the toolbox, 1) a functionality that estimates heat demand and heat density at geographical locations and therefore can be used to estimate district heating potentials and 2) a dispatch tool that can be used to model heat supply for certain heat demand of district heating grids.
The first part of the document has the main focus on the Hotmaps dispatch tool. The conclusions highlight that the Hotmaps dispatch tool has important properties for heat planning, emphasising its dependence on inputs from the user and local conditions. The tool is a relatively fast computing optimisation tool. This basic structure helps sustain and stimulate an explorative and iterative approach when searching for the technical solutions that may best fulfill the strategic objectives of the heat planning.
The analysis, however, also point out some limitations and attention points when applied for national strategic heat planning. This includes properties such as exogenously given electricity price based dispatch, lack of representation of other energy sectors and the absence of individual heating areas. The document further describes some possible extensions and adaptations of the Hotmaps tool for future work, beyond the Hotmaps project duration.
In conclusion, the Hotmaps dispatch tool – as a stand-alone tool – is best suited for local optimization rather than national strategic heat planning.
For strategic heat planning at national level, the functionalities for estimating district heating potentials can be combined with a tool like EnergyPLAN. Since EnergyPLAN is not designed to estimate heat demands and heat densities but treat these factors as inputs, the Hotmaps tool supplements well by feeding EnergyPLAN with these inputs.
A comparison is carried out between district heating potentials found in Heat Roadmap Europe and in the Hotmaps tool. The potentials found in Hotmaps (based on the corresponding functionalities in the toolbox, with default values applied) are generally smaller than the potentials identified in Heat Roadmap Europe. The effect of smaller district heating shares is subsequently evaluated at national system level in EnergyPLAN. This exercise is partly carried out to demonstrate how Hotmaps and EnergyPLAN may supplement each other in strategic heat planning analysis. The exercise shows that reduced potentials overall increase total fuel consumption at energy system level. While the district heating potentials must be subject to further research, the exercise demonstrates; 1) how Hotmaps toolbox can be applied in national strategic heat planning processes and 2) how district heating potentials below the Heat Roadmap Europe benchmark will increase fuel consumptions under the given assumptions.