Final Project Report: Heat Highway

FTI Initiative Energy Model Region - 3. Call for Projects Federal Climate and E nergy Fund – Handling by T h e A ustr i an Re sea rch P romoti on Agency FFG Page 1 of 91 FTI Initiative Energy Model Region Publishable final report Programme control: Climate and Energy Fund Programme management: The Austrian Research Promotion Agency (FFG) Final Report created on 30/11/2025 (version Rev. 01) Project title: Heat Highway Project number: 880797 FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 2 of 91 Call 3. Call FTI Initiative Energy Model Region Project Starting Date 2021-03-01 Project Ending Date 2024-08-31 Total duration of project (in months) 42 months Project holder (Institution) Energieinstitut an der Johannes Kepler Universität Linz Contact person Simon Moser Postal address Altenberger Straße 69, 4040 Linz Telephone +43 732 2468 5658 Fax - E-mail [email protected] Website https://energieinstitut-linz.at FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 3 of 91 Heat Highway Interregional heat transmission networks to enable industrial waste heat usage and fossil-free industry Authors: Simon Moser, Michael Denk, Anja Gahleitner, Michael Haml, Marie-Theres Holzleitner-Senck, Gabriela Jauschnik, Magdalena Pflügl, Stefan Puschnigg, Valerie Rodin, Katharina Rusch, Energieinstitut an der Johannes Kepler Universität Linz Helmut Berger, Myroslav Buryy, Thomas Eisenhut, Manuela Farghadan, Michael Feichtinger, Ambra Muca, Nicole Strommer, Allplan GmbH Philipp Gartlehner, Ars Electronica Linz GmbH & Co KG Verena Alton, Riel Blakcori, Tobias Forster, Klara Maggauer, Nicolas Marx, Stefan Reuter, Ralf-Roman Schmidt, Janik Trauner, Austrian Institute of Technology Gregor Offenthaler, Dorian Wessely, Business Upper Austria Wolfgang Baumgartner, Gregor Winkler, Energie AG OÖ Erzeugung GmbH Stephan Hofer, Thomas Berger, Energie AG OÖ Umwelt Service GmbH Philipp Oberndorfer, Markus Novak, eww AG Harald Dehner, Alois Resch, Christian Wagner, FH Oberösterreich F&E GmbH Rudolf Dimmler, Kremsmüller Anlagenbau GmbH Robert Schlesinger, LAT Nitrogen Linz GmbH Simon Glaser, Hubert Pauli, Linz Strom Gas Wärme GmbH Thomas Kienberger, Josef Steinegger, MU Leoben – Lehrstuhl für EVT (MU Leoben) Christine Öhlinger, OÖ Energiesparverband Thomas Steinparzer, Primetals Technologies Austria GmbH Michael Schwaiger, voestalpine Stahl Donawitz GmbH Thomas Keplinger, Thomas Moser, voestalpine Stahl GmbH FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 4 of 91 Table of content 1 Introduction ..................................................................................................................... 6 2 Content presentation ....................................................................................................... 9 2.1 Framework assessment for heat transmission networks ......................................... 9 2.1.1 Review of national/international best practice ................................................... 9 2.1.2 Legal requirements .........................................................................................13 2.1.3 Development of characteristic model cases ....................................................16 2.1.4 Potentials in addition to industrial waste heat: solar thermal, geothermal ........17 2.1.5 Competing solutions: mobile energy storage systems .....................................18 2.1.6 Replicability in Austria and Europe ..................................................................20 2.2 Tools for developing and evaluating heat transmission networks ...........................23 2.2.1 Toolbox development ......................................................................................23 2.2.2 Semi-dynamic flow calculation tools ................................................................24 2.2.3 Control algorithms ...........................................................................................24 2.2.4 Organizational aspects of heat transmission networks (network codes) ..........28 2.2.5 Business models and new players ..................................................................31 2.2.6 Lean HTN pipe technology ..............................................................................35 2.3 Use Case #1: HTN Linz ..........................................................................................39 2.3.1 Identification and Description of Heat Sinks ....................................................39 2.3.2 Defining the waste heat potential ....................................................................41 2.3.3 Identification of future waste heat sources .......................................................42 2.3.4 Identification of today waste heat sources .......................................................45 2.3.5 Pipe routing .....................................................................................................45 2.3.6 Business model ...............................................................................................46 2.4 Use Cases #2: HTN Upper Austria – Connection Wels-Linz ...................................47 2.4.1 Analysis of energy and waste heat potentials between Wels and Linz ............47 2.4.2 Heat Merit Order .............................................................................................50 2.5 Use Cases #2: HTN Upper Austria – other potentials .............................................53 2.5.1 Potentials in Upper Austria (outside the Wels-Linz region) ..............................54 2.5.2 Salzkammergut ...............................................................................................56 2.5.3 Ennshafen .......................................................................................................57 2.6 Use Case #3: HTN Styria .......................................................................................57 2.7 Follower Case #1: HTN Inntal ................................................................................60 2.8 Follower Case #2: HTN Innviertel ...........................................................................68 2.9 Follower potentials .................................................................................................72 3 Results and conclusions ................................................................................................76 3.1 Findings & Results (Lessons Learned) ...................................................................76 3.2 Communication & Dissemination ............................................................................78 3.2.1 Virtual demonstrator & Prototype ....................................................................78 3.2.2 Stakeholder participation & local involvement, Dissemination & international visibility 83 FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 5 of 91 4 Outlook and recommendations ......................................................................................86 5 Bibliography ...................................................................................................................87 6 Appendix ........................................................................................................................90 7 Contact details ...............................................................................................................91 FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 6 of 91 1 Introduction This report is the publishable final report for the Heat Highway project, which was carried out by 17 project partners between March 2021 and August 2024. The Heat Highway project focussed on supra-regional district heating networks and the resulting opportunity to make better use of industrial waste heat. Heat Highway was funded by the Klimaund Energiefonds as part of the 3rd call for proposals of the FTI Initiative Energy Model Region and co-funded by the regional government of Upper Austria. The project was handled by FFG Österreichische Forschungsförderungsgesellschaft mbH. The project is assigned to the Energy Model Region New Energy For Industry. The Heat Highway project contributes to the innovation fields of the New Energy For Industry Energy Model Region, namely in the areas of ‘Industry to Grid’, ‘System Solutions & Infrastructure’ and ‘New Business Models’. Supra-regional district heating networks and the resulting opportunity to utilise industrial waste heat more effectively are the central themes of Heat Highway. This results in two major topics: Firstly, it is about the feasibility and realisation of supra-regional district heating networks. These exist in practice in a few individual cases, but are either smaller than those considered in the project or involve fewer players. The Heat Highway project is the first major research project to address the theory of supra-regional district heating networks, while at the same time aims to advance practical use cases towards implementation. Secondly, industrial waste heat is underutilised. This is also due to the fact that waste heat is increasingly generated in the summer and local heating networks mainly need waste heat in the winter. In addition, the capacity that local heating networks can absorb is often limited; supra-regional connections can increase the sales volume, which provides the thematic link between the two areas. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 7 of 91 Figure 1: Overview of the concept of a supra-regional heating network and the derived objects of investigation. Illustration taken from: Moser, Puschnigg (2021). Supra-Regional District Heating Networks: A Missing Infrastructure for a Sustainable Energy System. Energies. 14(12):3380. https://doi.org/10.3390/en14123380 The use of industrial waste heat is essential for the decarbonisation of the heat supply. While the electricity transmission network connects many generation, storage and consumption units, the current options for waste heat feed-in and (supra)regional exchange are limited. Heat Highway is therefore investigating (supra)regional heat transmission networks (HTNs) that connect four areas: industrial waste heat and other sustainable sources, district heating networks, industrial process heat sinks and storage. These HTNs connect consumption centres and industrial sites and thereby cross areas with other heat sources and sinks. The project reduces risks by incorporating many supply and demand nodes and creating innovative business models. The concept goes beyond state of the art in terms of the number of players, (supra)regionality and networking. Heat Highway is developing two 100 km long HTNs in Upper Austria and Styria and is driving forward three sections for practical implementation, particularly in the central region of Upper Austria and in Linz. Furthermore, Heat Highway analysed an HTN in Styria, especially in the Mur-Mürz area, and initiated the next steps and stakeholder participation. The analyses in four ‘follower regions’ ensures the reproducibility. Various areas/disciplines are considered theoretically. These include regulatory, systemic-technical, economic and legal analyses. The HTN implementation is evaluated using all of these analyses/tools. Heat Highway aims to develop an interdisciplinary toolbox for anticipating the medium-term utilisation of waste heat from innovative processes and to develop a cost-effective pipe system. A highlight of the project is the prototype, which is a large district heating pipe with illustrative elements, designed FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 8 of 91 for the exhibition, as well as a virtual HTN demonstrator, which demonstrates the technical controllability of a system with several players. The following chapters describe the work carried out in the Heat Highway project and the results achieved. The division into sub-chapters in this report essentially corresponds to the work packages of the project and their underlying tasks. All work packages and tasks follow their own specific methods, which is why these are also presented in the content presentation. In Heat Highway, the aim was to disseminate scientific results in the best possible way, and therefore several research papers and conference contributions were produced. As these publications shall not to be repeated here in their entirety, short summaries are included or reference is made to the publications. This means that although the content and results are fully accessible, larger work packages or tasks can sometimes be relatively short. A central and integral part of the project was dissemination to the general public. This work is described in more detail in the chapter dissemination. Table 1: Overview (Sub)-Chapters corresponding to Work Packages and Tasks (Sub)-Chapters Work packages/Task 2.1 T2,1 Review of national/international best practice T2,2 Legal requirements T2,3 Development of characteristic model case T2,4 Competing solutions, further potentials s 2.2 T3,1 Toolbox development T3,2 Semi-dynamic flow calculation tools T3,3 Control algorithms T3,4 HTN organization (network codes) T3,5 Business models and new players T3,6 Lean HTN pipe technology 2.3 WP 4 Case 1: HTN Upper Austria – section LINZ (T4,1 – 4,5) 2.4 WP 5 Case 2: HTN Upper Austria – section WELS-LINZ (T5.2 – T5,5) 2.5 WP 5 Case 2: HTN Upper Austria – section OTHER AREAS (T5,1) 2.6 WP 6 Case 3: HTN Styria (T6,1 – 6,5) 2.7 WP 7 Follower Cases & Replicability (T7,1 INNTAL) 2.8 WP 7 Follower Cases & Replicability (T7,2 INNVIERTEL) 2.9 WP 7 Follower Cases & Replicability (T7,3 – T7,4) 3.1 WP 8 Virtual demonstration & Dissemination (T8,4 Lessons learned) 3.2 T8,1 Virtual demonstrator T8,2 Stakeholder participation & local involvement T8,3 Dissemination & international visibility T3,6 Prototype FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 9 of 91 2 Content presentation This chapter contains the central work content of the Heat Highway project. It is structured in the work packages or underlying tasks, each of which represents a subchapter. The content presentation therefore describes the objectives, methodology and results of the individual work packages or tasks. The results, particularly for tasks that deal with company-specific data, can only be presented to the extent that the required confidentiality of the data allows. Please note that reference is made to available publications such as scientific papers or conference contributions if the results have already been disseminated in this way by the project team before. 2.1 Framework assessment for heat transmission networks The results from the work package on the framework conditions for heat transport networks are presented in this subsection. 2.1.1 Review of national/international best practice In the effort to decarbonize energy systems, long-distance heat transport networks (HTNs) have emerged as a critical infrastructure for the efficient distribution of waste heat and renewable energy over large areas. Countries such as Austria, Germany, Denmark and the Netherlands are pioneering these systems and showcased different models of successful implementation. Further information can be found in the deliverable “Heat Highway - Review of Best Practice Examples” (see chapter 6 Appendix). Heat transport networks, classified here into unidirectional pipelines (HTP) and bidirectional transmission systems (HTN), allow for the movement of thermal energy across extended distances. These networks serve multiple regions and cities, integrating industrial waste heat, renewable energy, and biomass to provide a stable heat supply. They also contribute to a significant reduction in emissions by replacing traditional fossil-fuel-based heating systems. Table 2: Overview of long heat transport networks with basic information. In some cases, different parameters were found for identical networks (values in brackets). HTP = unidirectional transport pipe, HTN = heat transfer network. Location Country Type Lengt h in km Rated Power in MW Annual heating demand in GWh/a Pipe diameter in mm Dürnrohr-St. Pölten AT HTP 31 50 200 450 / 400 Hallein-Salzburg AT HTP 14 (19) 7,5 120 (80) 200 Pöls-Judenburg HTP Aichfeld AT HTN 18 30 100 300 / 250 FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 16 of 91 2.1.2.2.5 Status and Terminology of Waste Heat Waste heat, though not renewable energy, is equated with renewables in district heating assessments under RED III. However, its classification remains unclear, particularly when associated with fossil-driven processes. Introducing a unified term, such as "low-carbon heat," to encompass both waste heat and renewable energy-based heat could simplify its categorization and emphasize its climate-friendly potential. The proposed adjustments aim to clarify and expand the definition of waste heat, making it more inclusive, practical, and aligned with the goals of energy efficiency and decarbonization. These reforms would enable waste heat to play a more prominent role in transitioning to a sustainable, low-carbon energy system. 2.1.3 Development of characteristic model cases To facilitate the classification and derivation of different model cases for district heating networks, four key distinguishing features have been identified. These key characteristics are the generation, topology, network level, and structure of a district heating network. These characteristics are thoroughly analysed and detailed in Steinegger (2025) 3 . For an overview, they are briefly subdivided below. • Generations • First generation of district heating • Second generation of district heating • Third generation of district heating • Fourth generation of district heating • (Fifth and Sixth generation) • Topology • Radial grid • Ring grid • Meshed grid • Network level • Primary network level • Secondary network level • Structure • One central location • Central base load • Large integrated network • Peripheral base load • Common transmission pipe 3 Steinegger (2025). Assessing the Technical and Economic Feasibility of Supra-Regional District Heating Networks. Doctoral thesis, currently under review. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 17 of 91 A Heat Highway, as outlined and planned in this project, represents a supra-regional district heating network. This type of network can be described by the four key characteristics mentioned earlier and classified into different model cases, depending on how the characteristics outlined below are implemented. The supra-regional district heating network can exhibit characteristics of the second-generation district heating and higher, with the final generation level largely dependent on the temperature of the transmission line. This temperature is determined by the specific use case, as it must be sufficient to meet the highest temperature requirements of any connected district heating network within the supplied region. In terms of topology, the transmission line in a supra-regional district heating network typically follows a radial grid, while a ring grid may be used in special cases. Meshed grids are unlikely, as transmission lines carry the highest temperatures in the network, and minimising the length of these lines helps reduce temperature losses. The network level of the transmission line corresponds to a primary network level. The implementation of a supra regional district heating network may introduce an additional, previously undefined network level. This is because the transmission line could connect to DHNs that already have both primary and secondary network levels, requiring the reclassification of these networks as secondary and tertiary levels. Since a supra-regional district heating network is established by linking various DHNs and heat generation units through a heat transmission line, its structure would resemble that of a common transmission pipe. Furthermore, Moser et al. 4 define a supra-regional district heating network as one that spans large distances by using extended heat transmission lines. This network would link sources of industrial waste heat and renewable heat with heat sinks, such as district heating systems or large individual consumers, in a manner similar to the highvoltage grid in the electricity sector. 2.1.4 Potentials in addition to industrial waste heat: solar thermal, geothermal Within this project, a tool was developed to perform an approximate economic sensitivity analysis for large-scale solar thermal systems. The main purpose of the tool is to compare the economics of solar-supported district heating systems with those of conventional district heating systems. This includes the calculation of the levelized cost of heat (LCoH) of the solar thermal system and a comparison with the LCoH of conventionally operated district heating systems. The calculation of the LCoH considers the energy prices, lifetime of the components, costs for CO2-emissions, investment costs etc. As the initial calculation of investment costs is often a challenge, the tool provides the ability to estimate these with specific cost curves. This enables an initial estimation of the economic viability to be obtained at the outset of planning activities or feasibility studies with minimal effort. The comparison between the solar-supported 4 Moser (2021). Supra-Regional District Heating Networks: A Missing Infrastructure for a Sustainable Energy System. doi.org/10.3390/en14123380. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 18 of 91 and conventional district heating system is done via the cost ratio (CR) of the two calculated LCoH., see Figure 2. Figure 2: Result of the sensitivity analysis. In this manner, the parameters with the most substantial impact on the LCoH can be identified. In the shown case in Figure 2, the most significant parameters are the energy prices. In order to validate the developed tool, it was applied to real projects. The results show a consistent correlation between the individual project results and the calculation methods used in the developed tool. More details on this topic can be found in Wagner and Dehner (2024) 5 . 2.1.5 Competing solutions: mobile energy storage systems District heating networks (DHN) are contributing to an efficient and reliable heat supply, mostly for residential applications in urban areas. The energy sources for DHN are various, with a decreasing share of fossil fuels, as renewable energy technologies like biomass are steadily rising their contribution. Industrial waste heat can be considered as another renewable energy source with high potential for supplying DHN, however, industrial plants are usually located in the periphery, outside the economic range of DHN. The concept of mobile thermal energy storages (M-TES), as depicted by Figure 3, aims to bridge this distance between industrial heat source and DHN or other heat sinks by transporting the heat on already available infrastructure like roads or railways, and therefore, avoiding the need for extending the DHN. 5 Wagner, Dehner (2024). Sensitivity Analysis Of Solar District Heating Systems. Conference Proceedings EuroSun 2024, Paper accepted. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 19 of 91 Figure 3: Schematic illustration of the M-TES concept 6 During the project Heat Highway, the M-TES concept was thoroughly investigated, with the main goal to assess its economic viability in comparison to DHN. Therefore, three different kinds of storage technologies were considered, which were sensible storages, phase change materials (PCM) and thermochemical storage materials (TCM). Moreover, several types of storage material were analysed for each storage technology, with regard to their meaningful application in terms of temperature range, which is usually defined by the available heat source and the demanding heat sink. An economic model based on VDI2067 was developed that takes into account all boundary conditions given by the particular combination of storage technology and storage material, e.g. the energy density, which determines the number of required runs for transporting a certain amount of energy. The results of this economic analysis are illustrated by Figure 4. The considered M-TES configurations are categorised in three temperature ranges, defined by the source and sink temperatures. For each case, the costs of transported heat (COTH) are presented in €/MWh. The costs of heat provided by conventional DHN in Austria in 2022 serves as benchmark for the results of heat transport by M-TES. This comparison reveals that M-TES working with PCM and TCM, namely Sodium Acetate Trihydrate (SAT), Erythritol, Zeolite 13X and Zeolite 4A, can provide lower COTH than DHN. The cheapest solution would be the M-TES configuration using Zeolite 13X, resulting in COTH of 89.5 €/MWh, equal to a relative economic benefit of 40.3 % compared to DHN. 6 Resch, Dehner (2023). Economic Analysis of Mobile Thermal Energy Storages as Complement to District Heating. Environmental and Climate Technologies, Jg. 27, Nr. 1, S. 516-531. https://doi.org/10.2478/rtuect-2023-0038. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 20 of 91 Figure 4: Costs of transported heat (COTH) for the analysed M-TES configurations, in comparison to the heat costs of conventional DHN in Austria in 2022 However, these results are only valid for a distance of 7 km between heat source and sink, with a transported amount of energy of 1092 MWh/a. More detailed results, all economic parameters and considered material properties are documented in the corresponding publication from Resch and Dehner (2023) 7 . This investigation revealed that M-TES can be economically competitive to conventional DHN for distances below 10 km. Therefore, M-TES can serve as complementary technology to accelerate the integration of industrial excess heat as energy source for DHN. 2.1.6 Replicability in Austria and Europe Each region must be examined in detail to determine its suitability for a supra-regional district heating network. However, some regions are more favourable due to a high concentration of energy-intensive industries and the proximity of large district heating networks. Based on this, individual regions were analysed, focusing on existing heating networks near significant energy-intensive industries with substantial waste heat potential in Europe. For this purpose, many of the largest district heating networks in Europe, which are described in detail in Steinegger (2025) 8 , are analysed, along with the European heat road map 9 . Based on the potential length of the transmission lines for a supra-regional district heating network, the maximum annual heat consumption of district heating networks near industrial waste heat sources, and the technical potential (assumed to be 6% of the theoretical potential) of industrial waste heat, considering 3,000 full load hours, rough estimates for linear heat 7 Resch, Dehner (2023). Economic Analysis of Mobile Thermal Energy Storages as Complement to District Heating. Environmental and Climate Technologies, Jg. 27, Nr. 1, S. 516-531. https://doi.org/10.2478/rtuect-2023-0038. 8 Steinegger (2025). Assessing the Technical and Economic Feasibility of Supra-Regional District Heating Networks. Doctoral thesis, currently under review. 9 Europa-Universität Flensburg and Halmstad University (2018). Pan-European Thermal Atlas 4.3.heatroadmap.eu/peta4/ (Abgerufen am: 17.12.2024). FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 21 of 91 density were made, and potential regions were identified. These regions are listed in the following table: Table 4: Analysed regions Large Sinks Nation Heat Demand in GWh Theoretical Potential in GWh Technical Potential adjusted to 3000 FLH Length transmission line in km linear heat density in MWh/(m*a) Berlin GER 9578 7463 155 99 1.6 Warsaw POL 9472 11491 239 110 2.2 Espoo-Helsinki-Vantaa FIN 9987 5655 118 58 2.0 Ruhrgebiet GER Researched but not realised (still high potential) Bucharest ROU 5533 1933 40 65 0.6 Paris FRA 5500 9500 198 203 1.0 Munich GER 4800 5186 108 95 1.1 Gothenburg SWE 4400 5278 110 106 1.0 Krakow POL 2631 4844 101 33 3.1 Budapest HUN 2184 2653 55 27 2.0 → Leipzig GER 1735 5219 109 52 2.1 → Milan ITA 1226 6933 144 78 1.8 → Rotterdam NED Has already been partially implemented → Saarland GER 808 5139 107 6 17.8 → Breda-Tilburg NED 722 2042 42 21 2.0 → Amsterdam NED 611 5186 108 27 4.0 Due to the more precise data available on industrial waste heat in Austria compared to the rest of Europe, potential supra-regional district heating networks regions are identified by combining data from the Austrian Heat Map 10 with the calculation of the potential linear heat density. The given technical potential is standardised to 3000 full load hours, and only sources with temperatures above 50°C are considered. Regions previously identified and analysed in the Heat Highway Project, such as Lower Inntal in Tyrol, Innviertel, St. Pölten–Krems, Vienna South, Linz, and Styria, are excluded from this analysis. The results are presented in the following table: 10 Bundesministerium für Klimaschutz, Umwelt, Energie, Mobilität, Innovation und Technologie (2021). Austrian Heat Map. www.austrian-heatmap.gv.at (Abgerufen am:17.12.2024) FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 22 of 91 Table 5: Additional potential supra-regional district heating networks regions in Austria Location IWH Technical Potential in GWh IWH Technical Potential adjusted to 3000 FLH Length transmission line in km LHD in MWh/(m*a) Salzkammergut 299.9 102.71 34 3.02 Deutschlandsberg 102.4 35.07 21 1.67 Völkermarkt 163.2 55.89 12 4.66 St. Veit an der Glan 119.6 40.96 36 1.14 FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 23 of 91 2.2 Tools for developing and evaluating heat transmission networks The results from the work package on developed tools for heat transport networks are presented in this subsection. 2.2.1 Toolbox development To establish a consistent and structured framework for utilizing and interacting with the various simulation and calculation models from Work Package 3, the toolbox was developed as an overarching task. This toolbox aimed to ensure coherence within the work package and provided a unified starting point for the development of individual tools. These tools include the semi-dynamic flow calculation tool, control algorithms, HTN organization (network codes), business models and new players, and the lean HTN pipe technology & prototype. During the project, we identified that a bottom-up approach was most effective in gaining a comprehensive understanding of data and information requirements. Because of the heterogeneous of the tools, the critical questions were addressed within the individual tools, and the findings were discussed and consolidated in joint Work Package meetings and feedback loops. This collaborative process focused on defining data requirements, selecting appropriate databases, and ensuring interfaces and interoperability between the tools. Additionally, potential barriers and boundary conditions were evaluated that might impact the application of the tools and methodologies. By analysing the requirements of each individual tools, it has turned out that completely different data is required in the different tools. However, if you are dealing with the topic of industrial waste heat feed-in and/or supra-regional heating networks and would like to approach the topic, the following data should be analysed in advance as a very positive initial input, because this can help in almost all tools: • What is the situation regarding heat source or waste heat? Parameters: o Quantity o Performance o Profile o Temperature o Time horizon: all year vs. summer, all week vs weekend, weekdays, 24 hours per day vs 8 hours by day • Are there heating networks nearby? And if yes, what size do they have, what temperature level and what is the annual sales? • What alternative heat sources are available in the area (possibilities such as geothermal energy, solar thermal energy, etc.)? FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 24 of 91 • What alternative sources of waste heat are there in the area? • Are there any legal restrictions that can be circumvented by using waste heat? • Are there hydraulic guidelines that must be observed? • Which economic efficiency parameters are available individually and collectively? • Are there summer sinks? Who could take the waste heat in summer in order to utilise it all year round? 2.2.2 Semi-dynamic flow calculation tools For the following simulations of the different scenarios in the use cases, a new load flow calculation tool was developed, as detailed in Steinegger et al. (2022) 11 and Steinegger (2025) 12 . This tool was designed to meet the key requirements for calculating supra-regional district heating networks: • An easy implementation into existing multi-energy-system (MES) simulation frameworks, especially the HyFlow 13 framework. • The accurate calculations for small and large district heating networks, highly branched district heating networks, or district heating networks with long transmission lines, considering that these properties can occur individually or in combination. • The capability to consider temporally varying temperature changes within the district heating networks. • The ability to incorporate changes in the directions of the volume flows within the district heating network over various time steps. • Ensuring sufficiently fast calculation speeds. • The inclusion of typical elements of a heating network in the calculations. • The availability of a freely accessible code that allows for the integration of new operating strategies. The developed tool is based on a quasi-dynamic approach that satisfies all the mentioned requirements. Compared to other tools in the literature, this method offers lower calculation times than dynamic approaches and higher accuracy than steady-state approaches. 2.2.3 Control algorithms The report discusses technical challenges in implementing interregional heat transmission networks for the Heat Highway project. It focuses on the development and validation of control algorithms and operational strategies, incorporating available flexibility options. 11 Steinegger (2022). A new quasi-dynamic load flow calculation for district heating networks, doi.org/10.1016/j.energy.2022.126410. 12 Steinegger (2025). Assessing the Technical and Economic Feasibility of Supra-Regional District Heating Networks. currently under review. 13 Greiml (2022). Modelling and simulation/optimization of Austria’s national multi-energy system with a high degree of spatial and temporal resolution, https://doi.org/10.3390/en15103581. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 25 of 91 Further information can be found in the deliverable “Heat Highway - Control Algorithms (general)” (see chapter 6 Appendix). 2.2.3.1 Key Control Strategies for Heat Transmission Networks There are six basic control strategies 14 which operate simultaneously in a traditional DH network. These are usually implemented in the form of classical control such as rule based or PID. A graphical depiction is shown in Figure 5. (A to E are implemented at the production and pumping station level, whereas the control strategy F is implemented at the user substation level.) Basic Control in District Heating (DH) Systems: • Supply temperature control: Modulates heat generation to maintain a fixed supply temperature based on external conditions. • Minimum supply temperature control: Ensures sufficient supply temperature during lowdemand periods. • Pressure controls: Maintain minimum and maximum pressure limits to avoid system damage. • Heat demand and flow control: Implements climatic control at substations, ensuring proper heat delivery. Temperature Management in HTNs: • Heat exchange between industrial sources and HTNs requires balancing differing temperature levels, often needing heat pumps or post-heating systems to raise the temperature before heat enters the main network. • Managing multiple heat sources of varying temperatures can be optimized with additional lower-temperature lines and centralized post-heating to reduce energy loss. Thermal Energy Storage (TES): • Centralized TES can balance fluctuations in heat demand, while decentralized TES systems at substations or buildings enhance flexibility and reduce the need for larger distribution infrastructure. • TES is essential in long-distance heat transfer networks (LDHTNs) for decoupling production from demand, aiding in response to peak demands. 14 Buffa, Fouladfar, Franchini, Lozano Gabarre, Andrés Chicote (2021). Advanced Control and Fault Detection Strategies for District Heating and Cooling Systems—A Review, Applied Sciences, vol. 11, no. 1, p. 455, doi: 10.3390/app11010455. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 32 of 91 2.2.5.1.1 Domestic and commercial hot water use In Linz, DH for space heating and hot water can be obtained separately. According to DH experts, the potential of hot water to be utilized as a summer heat sink in the central Linz area is limited. This assessment is based on the fact that more than 80 % of heat consumers use DH for both hot water and space heating. The remaining share of customers obtain hot water from electrically operated boilers. It is possible to supply these consumers with hot water as part of a large-scale retrofit campaign, which is already being implemented in some cases. However, this conversion involves a great deal of effort (many buildings/flats to be retrofitted in comparison to low hot water demand) and investment costs. 2.2.5.1.2 Heat-to-cold / waste heat-to-cold During the summer months, waste heat could be harnessed by generating cold and feeding it into a district cooling network. The waste heat can power thermally driven absorption chillers, providing cooling for end customers. Linz already has some district cooling systems in place that utilize electrically driven chillers. In recent years, the demand for cooling in the city centre has grown significantly. As a result, there are plans to further expand the existing district cooling network and its generation capacity to meet the rising demand. Thermal chillers are technically complex and involve high investment costs, while the supply of cold is still limited to a low number of full load hours. 15 2.2.5.1.3 Low temperature process heat Waste heat generated during industrial processes can be utilised both inside and outside the production plant. The excess heat generated by primary industrial processes at higher temperatures can be recovered and utilised for secondary processes at lower temperatures. In this way, waste heat from primary processes can be used to replace other (fossil) fuels. It was shown that bilateral connections to provide process heat are feasible. 16 In order to deliver the waste heat at the highest usable temperature and to actually replace fossil process heat, DH networks would need to run at higher temperatures in summer, which is contradicting the current state of the art, as low temperatures decrease losses and increase pipeline lifetime. 17 2.2.5.1.4 Seasonal heat storage The FutureDHSystem Linz project 18 investigated how a large-scale heat storage system can contribute to shifting thermal energy from the summer to the winter period and whether this 15 Kapeller et al (2023) The effects of climate change-induced cooling demand on power grids. Energy Reports, Volume 11, June 2024, Pages 674-691. https://doi.org/10.1016/j.egyr.2023.07.028 16 Moser, Lassacher (2020). External use of industrial waste heat - An analysis of existing implementations in Austria, Journal of Cleaner Production, Volume 264, 10 August 2020, 121531, https://doi.org/10.1016/j.jclepro.2020.121531. 17 Moser, Puschnigg (2021). Supra-Regional District Heating Networks: A Missing Infrastructure for a Sustainable Energy System. Energies. 14(12):3380. https://doi.org/10.3390/en14123380 18 Moser et al (2017). FutureDHSystem Linz - Sondierung neuer Konzepte für zukünftige Energietransformationen im Linzer Wärmesystem. Final project report. Available: https://energieinstitut-linz.at/wpcontent/uploads/2023/04/Future-District-Heating-System-Linz-Endbericht.pdf (Abgerufen am: 19.12.2024). FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 33 of 91 large-scale heat storage system can be operated economically. The results found there and methodology applied are still valid, given an update to changed price levels. 2.2.5.1.5 Supply of new DHN or substitution of fuel-based DH energy The DH network in Linz supplies the city's consumers with thermal energy. The majority of the city area is supplied by LINZ AG. In addition to this large DH network, the company operates other smaller decentralised local heating networks in Haid and Marchtrenk. These local networks primarily use biomass and gas for heat generation, which could theoretically be substituted by industries’ excess heat. However, the extent of these networks’ summer heat demand is limited. 2.2.5.1.6 Heat-to-power / waste heat-to-power Linz and the central region of Upper Austria are home to many heat-intensive industries. These include, for example, the chemical industry as well as food, paper and cement production, among others. In the course of these industrial processes, the temperature level drops until waste heat is finally available. If this waste heat cannot be further utilised for the primary process due to the low temperature level, it can potentially be used for other internal processes. Another alternative is to convert the low-value thermal energy contained in the waste heat into electrical energy. The electrical energy generated can be utilised internally or fed into the local power grid. Low-temperature ORC processes are expensive and exhibit low efficiency levels while electricity prices are expected to be lower in summer. However, a Heat Highway can collect waste heat from multiple sources and may provide economies of scale. 2.2.5.2 Business models for industrial waste heat cooperations The aim of the national research project Industrial Excess Heat (INXS) 19 was to record and evaluate the existing waste heat potential of Austrian industry as completely as possible. As part of this effort, a national survey on existing waste heat cooperations was conducted. INXS was carried out in conjunction with the work and insights gained of the project Heat Highway; thus, the survey results are attributed to both projects and are presented below. The detailed scientific findings can be accessed in Moser and Jauschnik (2023) 20 . In order to obtain information on existing implementations of external waste heat utilisation in Austria, a questionnaire was created to generate a database for further analyses. The 45 waste heat cooperations surveyed by Moser and Lassacher (2020) 21 in 2018 served as the basis for establishing contacts. After publication of the paper, six further case studies were added to the list by December 2021, also by extending the system boundary applied. 19 More information on the project: https://energieforschung.at/projekt/industrial-excess-heat-erhebungindustrieller-abwaermepotentiale-in-oesterreich/ (Abgerufen am: 17.12.2024). 20 Moser, Jauschnik (2023). Using Industrial Waste Heat in District Heating: Insights on Effective Project Initiation and Business Models, Sustainability, Volume 15(13), 4 July 2023, 10559, https://doi.org/10.3390/su151310559. 21 Moser, Lassacher (2020). External use of industrial waste heat - An analysis of existing implementations in Austria, Journal of Cleaner Production, Volume 264, 10 August 2020, 121531, https://doi.org/10.1016/j.jclepro.2020.121531. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 34 of 91 The original questionnaire is five pages long and, in addition to an information sheet and general information on the cooperation, is divided into the following sections: • Section 1: How did the cooperation come about? • Section 2: How does the external heat supply work from a technical point of view? • Section 3: How does the external heat supply work from an economic point of view? • Section 4: How could risks and uncertainties be overcome? The questionnaire was sent out in December 2021, and responses were provided by means of written entries in the questionnaire or via a web or telephone interview, which made it possible to go into more detail on causality (internal validity). The survey was closed at the end of March. In total, responses were obtained for 24 of the 51 implementations, with 4 companies responding for more than one case and responses from 16 companies in total. It should be emphasised in advance that these were individual projects and the solutions are correspondingly specific. This also means that the limited number of cases means that the results are not statistically significant - however, the questions asked and the fact that interviews were also used to obtain the answers guarantee an argumentative causality. The following success factors and business models can be derived from the answers received. 2.2.5.2.1 Success factors • Open handling of information gives the cooperation partners certainty about the business model and allows them to better weigh up risks. • Major changes on the part of one of the cooperation partners prompt the active search for partners and the pursuit of the necessary negotiations. Only very good, existing relationships between the cooperation partners make it possible for projects to be initiated even without the impetus of such major changes. • Third parties can also initiate co-operations: Municipal politicians, interest groups, agencies are in some cases decisive for initiation. • External waste heat utilisation takes place between two partners. As soon as one partner does not feel fairly treated in the allocation of profits, failure is likely. A high level of transparency regarding the necessary costs and achievable savings increases trust. • Existing generation systems bridge planned production downtimes and act as a backup in the event of unplanned outages of the waste heat supplier. Their presence also provides a cost reference. • It is necessary to recognise the risks of waste heat utilisation and that they are difficult to outsource in a joint project. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 35 of 91 2.2.5.2.2 Business models • The majority of implementations creates clarity through an exact interface, e.g. a heat exchanger or heat metering. At this point, the separation of investment, responsibility (maintenance) and billing takes place. This is not an obligation for success but increases clarity. • In most cases, billing is primarily in euros/MWh, often (but not always) supplemented by individual special provisions such as minimum quantities. Rents allow the heat network operator to locate its property on the industrial premises. • Fairness is created on the one hand by covering the costs and on the other - which can be observed almost everywhere - by indexing the value of the waste heat. • ‘Risks lead to contractual content’: this includes the aforementioned indexation and minimum quantities, but also prohibitions on potential alternatives, rights of first refusal on land or generation plants, etc. • Taking fewer risks, giving fewer guarantees or making fewer investments than the cooperation partner leads to a lower share of the joint revenue. The heat network operators often invest ‘into’ the industrial company via the interface, which also reduces the price of the waste heat. If industrial companies act as full-service suppliers of a heating network, the price of the waste heat increases. 2.2.6 Lean HTN pipe technology Selecting the right combination of DH pipeline technologies is key to efficient district heating systems. Planners and engineers must consider factors like area layout, energy demand, available resources, environmental impact, and economic feasibility. Each choice affects system efficiency, maintenance needs, and costs. Recent advancements in DH pipeline materials, such as high-density polyethylene and cross-linked polyethylene, are offering alternatives to traditional steel, valued for their corrosion resistance and flexibility. This task consolidates research and case studies to guide stakeholders in optimizing DH pipeline design and management for sustainable, energy-efficient heating. Another objective is to construct a lean, physical Heat Highway demonstrator at the Ars Electronica Center, highlighting sustainable district heating’s role in modern energy systems and raising public awareness. Further details are available in deliverable “Heat Highway - DH pipeline technologies” (see chapter 6 Appendix). An overview of the pipe technologies regarding their characteristics is shown in Table 6, and illustrated in Figure 6. The existing pipe technologies are: • KMR: Plastic composite pipe (Kunststoffverbundmantelrohr) • PMR: Plastic medium pipe (Kunststoffmediumrohr) • MMR: Metal medium pipe (Metallmediumrohr) • GRP: Glass fibre reinforced plastic pipe (Glasfaserverstärktes Kunststoffrohr) FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 36 of 91 • HTR: Pre-insulated high-temperature pipes (Hochtemperaturrohr) • SMR: Steel casing pipe (Stahlmantelrohr) Table 6: Overview of the pipe systems and their most important properties 22 Tube system Scope Available lengths Double pipe design up to DN Feature Maximum permissible operating temperature Continuous operating temperature Nominal pressure PN Nominal diameter DN Rods Rollers °C °C bar - m m - - PMR 95 80 6 20-150 12* Up to 780 DN50 Relatively favourable Limited pressure and temperature resistance KMR 160 Up to 130 (140 only for peak temp.) 25 201200 (usually DN20 - DN800) 6/12/16* - DN200 Due to the standardization and robustness the most widely used pipe system GRP 160 160 16 251000 6* - - Relatively expensive, only for special corrosion resistance requirements MMR 180 Up to 160 25 20-150 12* Until 1000 DN50 Relatively expensive, justified if the laying conditions make it necessary HTR - 250 - 20-400 - - - Relatively expensive, only if temperature 22 Nussbaumer, Thalmann, Ködel (2017). Planungshandbuch Fernwärme, Schweiz: Energieschweiz und QM Fernwärme Logstor Industry, "Vorgedämmte HT-Rohre – wie geschaffen für hohe Temperaturen," [Online]. (Abgerufen am: 27 01 2020) Kremsmüller A., Interview zu Projekterfahrungen. 2023 FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 37 of 91 Tube system Scope Available lengths Double pipe design up to DN Feature Maximum permissible operating temperature Continuous operating temperature Nominal pressure PN Nominal diameter DN Rods Rollers °C °C bar - m m - - conditions make it necessary SMR 400 400 64 251200 16* - ** Relatively expensive, only if the pressure, temperature or installation conditions make it necessary *Standard length/s, other lengths available on request. ** Special designs possible on request (e.g. multiple tube design). Figure 6: Existing pipe technologies on the market Constructing a lean district heating pipe system involves optimizing various factors to achieve minimal heat losses, temperature requirements, ease of installation, cost efficiency, and reliable welding processes. To minimize heat losses, it is essential to select pipe diameters that balance minimal heat loss with manageable pressure losses. Effective insulation is crucial, and using high-performance materials like polyurethane foam or mineral wool with optimized FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 38 of 91 thickness helps balance heat loss reduction and cost, but they must be economically viable. Consequently, the design and implementation of DH pipes and systems involve a careful balance of various factors to optimize efficiency, cost, and reliability. The critical aspects of district heating pipes include: • Pipe dimension and heat losses • Insulation thickness • CAPEX • Pressure losses • Buried vs. above ground laying • Flexibility and parallel pipes • Installation under pre-tension • Integration with heat pumps • Operational processes • Economic considerations Cost comparisons were based on the KMR pipe technology. PMR pipes are approximately 20% less expensive, while MMR pipes are roughly twice as expensive. No general pricing data is available for glass fibre pipes (GRP). HTR pipes are estimated to cost 5 to 10 times more, and SMR pipes about 10 times more. Although pipe technology prices provide a rough estimate for cost calculations, they need to be evaluated on a case-specific basis. In addition, a physical "Heat Highway" prototype was developed and constructed, incorporating the technical characteristics and requirements discussed. The prototype was exhibited at the at the Ars Electronica Center (AEC) in Linz. This prototype, in combination with a developed virtual demonstrator, showcases cutting-edge thermal energy technology and engineering innovation, offering visitors an engaging and interactive experience. Designed with key characteristics in mind, the prototype aligns with exhibition standards to effectively communicate the basic principles of sustainable district heating and raise awareness of heat supply. Its design enables visitors to easily comprehend the core concepts of sustainable district heating, emphasizing its critical role in modern energy systems and its potential to reduce environmental impacts. The prototype integrates the fields of energy engineering, research, and exhibition design, providing visitors with an optimal learning experience. This collaborative effort ensures that the prototype is both informative and accessible, making complex engineering concepts easy to understand and relatable for a broad audience. More information to the virtual and physical prototype can be found in the chapter 3.2.1, respectively. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 39 of 91 2.3 Use Case #1: HTN Linz 2.3.1 Identification and Description of Heat Sinks There are two district heating networks in Linz – the Linz AG and the Kelag network. As the Kelag network is already supplied with waste heat by voestalpine, the focus was on the Linz AG district heating network. The identification and description of suitable heat sinks in the Linz AG network is a decisive step in order to better utilise the potential for the use of waste heat and renewable energy. This requires a detailed analysis of the existing infrastructure, consumption profiles and heat demand dynamics. It is important to analyse the Linz AG plants so that they can be used as a benchmark. Figure 7: Illustration of the Linz AG district heating generation mix 23 (Financial year 2023, district heating mix changes annually depending on the operation of the systems) 2.3.1.1 Brief overview of two Linz AG heating plants 2.3.1.1.1 District heating plant Linz-Mitte 24 25 • District heating power plant with storage facility, gas and steam turbine plant, biomass plant and waste-to-energy plant 23 Linz AG (2023). Aktualisierte Umwelterklärung. Für den Bereich Energieerzeugung GJ 2023. https://www.linzag.at/media/dokumente/linzag/energieerzeugung/umwelterklaerung-gj23.pdf (Abgerufen am: 26.09.2024). 24 Linz AG (ohne Jahr): Fernheizkraftwerk Linz-Mitte. https://www.linzag.at/portal/de/ueber_die_linzag/unternehmen/gesellschaften/linz_strom_gas_waerme_gmbh/ene rgieerzeugung/fernheizkraftwerk_linz_mitte# (Abgerufen am: 26.09.2024). 25 Linz AG (2022). Pressekonferenz: Ein Öko-Turbo für mehr Erneuerbare Energie. https://www.linzag.at/portal/de/ueber_die_linzag/unternehmen/gesellschaften/linz_strom_gas_waerme_gmbh/ene rgieerzeugung# (Abgerufen am: 26.09.2024). // Linz AG (ohne Jahr): Energieerzeugung. https://www.linzag.at/media/dokumente/presse_2/linz_ag_gas_waerme_5/PK_Erneuerbaren_Offensive_Startsch uss.pdf (Abgerufen am: 26.09.2024). FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 40 of 91 • Annual electricity generation: 741 GWh and annual district heating generation 906 GWh • Storage facility: With a height of 65 metres and a storage volume of 35 million litres, the district heating storage facility at the FHKW Linz-Mitte is one of the largest storage facilities in the world. The storage system is used to reduce the utilization of peak-load boilers. • The waste-to-energy unit has a thermal capacity of 47 MW and an electrical capacity of 15 MW. The biomass unit provides a thermal capacity of 21 MW and an electrical capacity of 9 MW. • The total capacity of the gas-fired CHP unit is 171 MW thermal (unit 1a: 85 MWth, unit 1b: 86 MWth) and 227 MW electrical. The electrical capacity is divided into 73 MW from the gas turbine and 30 MW from the steam turbine at unit 1a, and 77 MW from the gas turbine and 47 MW from the steam turbine at unit 1b. The overall efficiency of the Linz-Mitte gas CHP unit is 88%, with an electrical efficiency of 50%. 2.3.1.1.2 District heating plant Linz-Süd 26 27 • The main components are three gas turbine units with an electrical output of 40 MW each, three downstream waste heat boilers (to utilise the waste heat from the gas turbines and to generate steam) and two steam turbine units with an electrical output of 36 MW and 16 MW respectively. • Annual electricity generation: 490 GWh and annual district heating generation 350 GWh • The total thermal capacity of the gas CHP unit is 150 MW. • The overall efficiency of this gas-fired CHP unit is 87%, with an electrical efficiency of 46%. To meet additional heat demand, a gas heat only boiler to cover peak-demand with a total capacity of 116 MWth is also available. Looking ahead, a flue gas heat exchanger is planned to address Linz’s growing district heating demand. With an additional capacity of 25 MWth, producing approximately 130,000 MWh of heat annually, this system will further increase the share of renewable energy in district heating production. // Moser et al (2017). FutureDHSystem Linz Sondierung neuer Konzepte für zukünftige Energietransformationen im Linzer Wärmesystem,“Energieinstitut an der Johannes Kepler Universität Linz. Linz AG, Linz und Wien: AIT Austrian Institute of Technology GmbH. 26 Linz AG (ohne Jahr): Fernheizkraftwerk Linz-Süd. https://www.linzag.at/portal/de/ueber_die_linzag/unternehmen/gesellschaften/linz_strom_gas_waerme_gmbh/ene rgieerzeugung/fernheizkraftwerk_linz_sued# (Abgerufen am 26.09.2024). 27 Linz AG (2022). Pressekonferenz: Ein Öko-Turbo für mehr Erneuerbare Energie. https://www.linzag.at/portal/de/ueber_die_linzag/unternehmen/gesellschaften/linz_strom_gas_waerme_gmbh/ene rgieerzeugung# (Abgerufen am 26.09.2024).// Linz AG (ohne Jahr): Energieerzeugung. https://www.linzag.at/media/dokumente/presse_2/linz_ag_gas_waerme_5/PK_Erneuerbaren_Offensive_Startsch uss.pdf (Abgerufen am 26.09.2024). // Moser et al (2017). FutureDHSystem Linz sondierung neuer Konzepte für zukünftige Energietransformationen im Linzer Wärmesystem,“Energieinstitut an der Johannes Kepler Universität Linz. Linz AG, Linz und Wien: AIT Austrian Institute of Technology GmbH. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 41 of 91 2.3.2 Defining the waste heat potential An important step in the joint preparation of the situation for waste heat recovery and waste heat reintegration was the agreement on waste heat terminology. This chapter provides an overview of various potential concepts, focusing on the definition of potential. In his fifth excursus, Michael Piot offers detailed definitions of individual potentials to ensure consistent use of terminology. His excursus serves as an excellent summary, which will be briefly presented in the following chapter. 28 • Theoretical potential: ‘The theoretical potential of a renewable energy describes the energy supply that can theoretically be physically utilised within a given region at a given time or within a given period of time.’ 29 • Technical potential (see Figure 8): ‘It is the proportion of the theoretical potential that can be utilised, taking into account the given technical restrictions.’ 30 The following diagram is intended to provide an overview of how the various concepts of technical potential can be differentiated. Figure 8: Technical Potential - terms in graphical representation (numbers = partial areas) Source: Michel Piot (2006) 5. Exkurs: Potenzialbegriffe. In: Schweizerisches Bundesamt für Energie (2007) Die Energieperspektiven 2035 – Band 4. Exkurse. 28 Piot (2006). 5. Exkurs: Potenzialbegriffe. In: Schweizerisches Bundesamt für Energie (2007) Die Energieperspektiven 2035 – Band 4. Exkurse. Link: https://inis.iaea.org/collection/NCLCollectionStore/_Public/43/004/43004108.pdf (Abgerufen am: 09.12.2024). 29 Kaltschmitt, Streicher, Wiese (2005). Erneuerbare Energien: Systemtechnik, Wirtschaftlichkeit, Umweltaspekte, Springer, Berlin. 30 Kaltschmitt, Streicher, Wiese (2005). Erneuerbare Energien: Systemtechnik, Wirtschaftlichkeit, Umweltaspekte, Springer, Berlin. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 48 of 91 Figure 12: Map showing the locations of the companies identified and analysed in terms of their energy requirements and waste heat potential along the Wels-Linz route. The survey gathered information from participating companies to assess their energy needs and waste heat potential. Companies were asked about their energy consumption, including their annual heating and hot water demand and the types of energy sources they use. Furthermore, companies were questioned about the presence of processes that produce waste heat, the quantity and temperature of this heat, and whether it varies by season or operating schedule. They were also asked if the waste heat is utilized internally and whether certain processes require cooling to dissipate heat. Additionally, the survey explored the cooling requirements of the companies, both for room cooling and process-specific needs, including their annual cooling demand and the processes relying on cooling. This data aimed to provide insights into potential synergies for waste heat recovery and energy optimization along the Wels-Linz corridor. 2.4.1.1 Key findings Out of the 200 identified companies, 90 were contacted and 25 responded, yielding a response rate of approximately 28%. As illustrated in Figure 13 the responding companies were predominantly from the metal and food industries. Most participating companies were large enterprises, with small and medium-sized enterprises accounting for only three of the responses. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 49 of 91 Figure 13: Sector distribution showing the percentage shares of various industries. 2.4.1.1.1 Heating Demand The 25 responding companies reported a combined annual demand for heating and hot water of approximately 40 GWh/a. About 6 GWh/a of this demand is currently met by district heating networks. Extrapolating this data for the 90 relevant companies suggests a total heating and hot water demand of up to 150 GW/a. However, due to the greater focus on the more relevant companies, the actual total is probably lower. 2.4.1.1.2 Waste Heat Potential Out of 25 surveyed companies, 18 indicated that their processes generate waste heat. Waste heat is generated from various operations such as chemical production, food manufacturing, compressor systems, cooling and refrigeration units, glass tempering furnaces, baking ovens, thermoforming, and drying processes. 11 companies already utilize the waste heat internally, while no external use was reported. Common applications include heat recovery from compressors, refrigeration systems, and production equipment. For most companies, waste heat is generated continuously. However, nearly none provided quantitative data on the temperature or quantity of waste heat, often due to a lack of measurements. There are minimal operational differences between summer and winter, though waste heat utilization is mostly limited to winter months. 2.4.1.1.3 Cooling Demand Among the surveyed companies, 11 out of 25 reported having processes that require cooling. These processes are primarily related to the cooling of machinery and casting systems, as well as the use of refrigerators and freezers. Nine companies provided information on their cooling energy requirements, which collectively amount to an estimated 8 GWh/a. However, the data indicates significant uncertainties regarding the exact quantities of cooling needed, the timing FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 50 of 91 and duration of cooling operations, and the specific temperatures required. This underscores the need for more precise data collection to better understand and optimize cooling energy demands. 2.4.1.2 Conclusion The surveyed companies showed a general interest in the Heat Highway project and in utilizing waste heat. The findings suggest that there is no significant waste heat potential in this area. However, there is a notable demand for space heating and hot water. The 25 responding companies reported a combined heating and hot water demand of around 40 GWh/a. When extrapolated to the 90 targeted companies, or the total of 200 companies in the region, the overall energy demand is estimated to be significantly higher. Additionally, there is further potential for waste heat utilization from smaller businesses and residential buildings. Local district heating networks, particularly in Marchtrenk and Haid, present potential sinks for the Heat Highway. Their consumption should also be considered. Existing district heating networks could replace biomass with waste heat, although the heating plant capacities themselves must remain intact. The combined heating demand of the surveyed companies, alongside the broader potential across all identified firms, underscores the significant energy needs in the area. However, precise quantification of waste heat and its characteristics remains challenging due to data gaps. 2.4.2 Heat Merit Order 38 As part of the Heat Highway project, a tool was developed to economically analyse the integration and connection of multiple players in a district heating network, including the feedin of renewable energy sources, waste incineration units and industrial waste heat. The socalled ‘heat merit order’ ranks the marginal costs of the generation units of the district heating system and thus represents the actual supply curve of the district heating network. The term ‘merit order’ is used to describe the ranking of power plants for operation in the electricity sector. Based on this term, the operating order of the heat generation units is referred to as the ‘heat merit order’. From the perspective of economic theory, the heat merit order represents the short-term supply curve or marginal cost curve for the local district heating market. The heat merit order is shown in a cost curve, where the price is shown on the ordinate and the current output is shown on the abscissa (MW) and not the amount of energy (MWh). The merit order curve orders the heat generation units according to their current variable costs, starting with the most cost38 Moser, Puschnigg, Rodin (2020). Designing the Heat Merit Order to determine the value of industrial waste heat for district heating systems. Energy 200, 117579. // Rusch, Moser (2025) Economic feasibility of implementing supra-regional connections of existing district heating networks. Submitted/Forthcoming. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 51 of 91 effective unit on the left. Due to the manageable number of relevant heat generation plants in a local district heating system, the individual generation units can be identified in the merit order curve. The data used for the development and application of the heat merit order model mainly comes from publicly available sources. The capacities of the heat generation units are generally known or were collected as part of expert interviews with project partners from industry. The following variable cost parameters were identified and included in the development of the heat merit order: energy input costs of the heat generation plant (e.g. gas costs), electricity output revenues of cogeneration units (e.g. spot market for electricity), costs for CO₂ certificates (e.g. from the emissions trading system), energy taxes: taxes on energy inputs (e.g. gas tax), variable network tariffs for energy input (e.g. gas grid), variable grid charges for energy outputs (e.g. electricity grid), costs directly associated with generation (e.g. disposal of ash, operationdependent maintenance). The marginal costs for the heat units were developed based on these cost parameters and adjusted with the technology-dependent efficiencies. To apply the heat merit order, three steps must be followed. (1) First, the heat demand of a district heating network is calculated using a temperature-based approach, (2) then the marginal costs of each generation unit are calculated and (3) finally, the heat generation units are ranked for each hour in ascending order based on the marginal costs. Based on this, it can be determined hour by hour which heat generation units cover the specific heat demand. First, the unit with the lowest marginal costs is utilised up to its maximum capacity, followed by the next unit with the second-lowest marginal costs. Generation units are utilised in this order until the entire heat demand for the respective hour is covered. Finally, the total cost of meeting the heat demand is calculated by summing the costs for each hour. For each hour, the marginal cost value of a unit is multiplied by the amount of heat generated. The following figures show two examples of an order of heat generation units in Linz. The examples are taken from the publication by Moser et al. (2020). In both figures, one Waste-toEnergy CHP, one Biomass CHP, two Gas CHP and three Gas Heat Only Boilers are ranked in ascending order based on their marginal costs. Figure 14 describes the scenario of one exemplary hour in winter. In winter, the demand for heat is high, so that the Waste-to-Energy CHP, the Biomass CHP and the first Gas CHP are utilised at full thermal capacity and the second Gas CHP is utilised at part of its thermal capacity in order to cover the heat demand in Linz. Figure 15, on the other hand, shows an exemplary hour in summer. As the demand for heat is low in summer, the Waste-to-Energy CHP is sufficient to cover the demand. Both examples are based on the price of a unit of heat, which is positive in Figure 14 and negative in Figure 15. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 52 of 91 Figure 14: Order of units in the heat merit order model in an exemplary hour in the winter. According to marginal costs, the first three units are utilized to their full thermal capacity. The thermal capacity of the fourth unit is only partly useduntil the total heat demand is fully covered. Source: Moser, Puschnigg, Rodin (2020). Designing the Heat Merit Order to determine the value of industrial waste heat for district heating systems. Energy 200, 117579. Figure 15: Order of units in the heat merit order model in an exemplary hour in the summer. To cover the total heat demand, only parts of the thermal capacity of the first unit – according to marginal costs – is utilized. Source: Moser, Puschnigg, Rodin (2020). Designing the Heat Merit Order to determine the value of industrial waste heat for district heating systems. Energy 200, 117579. The heat merit order is currently subject to restrictions that prevent the reflection of actual technical and economic conditions. These include the flexibility and ramp behaviour of heat generation units, heat losses, transport times among others. In addition, the fixed costs of heat generation units are not taken into account. Fixed costs include investment and construction costs as well as personnel, who are also indispensable during a shutdown. The fact that fixed costs are not considered is the main difference between the heat merit order approach and the LCOE (Levelized Cost of Energy) approach. Moreover, electricity prices can become negative, which is not taken into account in the heat merit order. As part of the Heat Highway project, the heat merit order was used to analyse the economic viability to create a Heat Highway, i.e. a connection by means of a Supra-Regional District FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 53 of 91 Heating Network (SR-DHN) (Moser and Puschnigg, 2021) between Linz and Wels, cities 30 km apart from each other. SR-DHN link existing district heating systems and can thus increase the security of supply, reduce the risk of outages and make better use of sustainable and costeffective energy sources. The heat merit order was applied to the use case ex-post over a period of four years, from January 2018 to December 2021. The system comprises a total of ten units, with the base load being covered by two Waste-to-Energy CHP units. These are supplemented by one Biomass CHP unit and five Gas CHP units in Linz and one Gas Heat Only Boiler unit in each city for peak loads and as a reserve. Essential for understanding the results is that the connection introduced in the simulation always enables optimisation, the savings are always ≥ 0. In the worst case, the simulation would not use the SR-DHN and operate the local plants as before. It is therefore clear that the savings must first justify the construction and operation of the line and that no simple statement on the economic viability of the line can be derived from the result. The substitution of units follows a clear seasonal pattern: when demand is high in winter, the units primarily cover their own district heating networks’ heat demand, so there is little heat left to be shifted. In summer, the two Waste-to-Energy CHP cover local demand. Particularly in the transitional periods in spring and autumn, heat from the Wels is shifted to Linz in the simulation. In Linz the dispatch of Gas CHP is significantly reduced. Overall, the establishment of a SR-DHN leads to a reduction in the variable costs of heat generation by an average of 16.3% per year (other cost components of district heating provision such as network costs or fixed costs of the plants are not considered in the simulation; for economic feasibility, the cost reductions must outweigh necessary investment costs). 2.5 Use Cases #2: HTN Upper Austria – other potentials The Upper Austrian central region, which includes the cities of Linz, Wels, Steyr and Enns, as well as the northern Salzkammergut, is relatively densely populated. There is also a pronounced industrial structure along the main transport route, such as the A1 motorway, the B1 federal road and the Westbahn train corridor. In the analysis by Moser and Puschnigg (2021), a potential course of a heat transmission network in Upper Austria was analysed. This process is based on consumption centres, industrial waste heat potential and existing combined heat and power plants or district heating networks. The process is based purely on this information and does not take into account technical and economic feasibility or detailed data on the networks and companies. Moser and Puschnigg (2021) estimated that the total waste heat potential of the analysed companies is approximately 230 MW in the summer period and 130 MW in the winter. Additional potential comes from thermal power plants and waste incineration plants, contributing around 200 MW. Moreover, the two largest industrial companies were assessed with a minimum potential, as they report no (economic) waste heat potential. However, if their waste heat potential were to account for just 1% of their energy consumption, the total industrial waste heat potential would double. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 54 of 91 The Heat Highway project also takes into account other possible decarbonised resources such as geothermal energy and solar thermal energy, which also have regional potential and would not be exploited without the Heat Highway. Figure 16: Case study results: possible routing of a SR-DHN in Upper Austria. Illustration taken from: Moser, Puschnigg (2021). Supra-Regional District Heating Networks: A Missing Infrastructure for a Sustainable Energy System. Energies. 14(12):3380. https://doi.org/10.3390/en14123380 Three analyses are described in more detail below, which analyse specific topics (waste heat and demand from companies) and the implementation of certain potentials. 2.5.1 Potentials in Upper Austria (outside the Wels-Linz region) 2.5.1.1 WKO survey on industrial waste heat potentials in Upper Austria In May 2022, a survey on waste heat potentials of the Upper Austrian industry was sent out to around 600 industrial companies in cooperation with the Upper Austrian Chamber of Commerce. The goal of the survey was to assess the waste heat potential of local businesses and, ideally, identify opportunities for heat-related collaboration. Additionally, the questionnaire FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 55 of 91 highlighted key aspects for the companies, such as the potential to utilise their waste heat externally or benefit from the waste heat generated by other companies. The industrial companies surveyed were able to provide information in the following areas: • General information about the company (e.g., name, address) • Number of production sites • Description of waste heat at production site(s) • General questions (e.g., payback periods, energy cost) An analysis of the survey results revealed that 47 out of 600 companies responded, with more than half being large enterprises. The remaining respondents were small and medium-sized enterprises (SMEs), highlighting that energy management is also a significant concern for smaller businesses. Half of the respondents, representing various sectors, reported that they do not utilize waste heat, either internally or externally. The sources of waste heat were highly specific to each company. While four of the responding companies are located within the city centre of Linz, the others are spread across Upper Austria. Although the limited data prevents drawing significant conclusions for Linz, the survey still provided valuable insights into the current waste heat management practices of local industrial companies. 2.5.1.1.1 Conclusion & Results The use of waste heat and the topic of energy are important not only for large companies but also for small and medium-sized enterprises. Waste heat at the main production site: Around half of the responding companies have unused waste heat that they do not use internally or pass on to third parties (mainly district heating networks). Companies with waste heat come from all sectors of the economy, from the food industry to the non-ferrous metals, paper, stone and wood industries through to the chemical and steel industries. The type of waste heat is very company-specific - from a few kW of heat output to high waste heat quantities in the double-digit GWh range and from low temperatures of 25°C to well over 300°C. Despite known efforts in some cases, there is still no customer for this. The temperatures and energy quantities recorded in the survey show that companies should consider using the waste heat of another company as a heat input for their own company. CO2 neutrality: Around 10% of companies state that their production is already CO2-neutral and around 50% state that they have a roadmap, strategy or concept for switching to CO2neutral production. Compensation measures to fulfil CO2 neutrality play a key role for around a third of the companies. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 56 of 91 The years from 2027 to 2040 are primarily stated as the time horizon for achieving the target; only three of the companies define 2050 as the target horizon. Only a quarter of the companies would like advice on switching to CO2-neutral production. Energy prices, amortisation: With regard to the current developments in energy prices (since the last year of the survey) and in Ukraine, the companies stated that there have been enormous price increases in some cases, although in some cases these are secured by longerterm contracts. This is also driving the implementation of measures. Although amortisation periods have decreased due to energy prices, the amortisation periods for energy-related projects have increased from approx. 5 years to 5.5 years according to the companies (20192022). 2.5.2 Salzkammergut The potential for the extended, additional utilisation of an existing waste heat source was evaluated and the utilisation possibilities were analysed. This resulted in the utilisation of the waste heat, especially in the summer months for other customers outside of Gmunden (these are already supplied via the current district heating system based primarily on waste heat and natural gas), which have an almost constant heat consumption throughout the year. For the substitution natural gas-based district heating, there is the potential for a total of 16 GWh/a. In order to expand the utilisation of the existing waste heat source and to ensure the required flow temperature of around 120 °C for the customers' technological processes, an expansion of the existing industrial heat extraction system was evaluated. The concept envisages further waste heat extraction parallel to the existing extraction for the Gmunden district heating network. The existing Gmunden network is primarily supplied by the existing recovery system. Further available waste heat can be utilised by other customers via the connecting pipeline. The course of the route was optimised and defined. Route inspections were carried out on site for the realisation of the pipeline planning. The project has the potential to achieve CO₂ savings of approximately 3,600 tons per year. Key investments include the expansion of waste heat recovery systems, the construction of a 5 km district heating pipeline (DN200), and the integration of the customer system. The total project costs are estimated at around €10.5 million. Following main findings have been identified: • CO2 price has little impact on profitability • Upcoming funding opportunity: transformation of the industry • Real reduction in the amount of usable waste heat due to existing waste heat source in the target system • Not economically viable due to falling natural gas prices (reference prices) FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 57 of 91 2.5.3 Ennshafen This was a highly successful example in identifying potentials and initiating negotiations. An additional output of the WKO survey on industrial waste heat potentials in Upper Austria was, that companies responded to have a waste heat potential. Based on previous projects, neighbouring and involved companies were contacted. Potentials for industrial steam and/or hot water networks in Enns were assessed. The energy institute moderated the first joint meetings and first data provision. Finally, cooperation of two companies turned out to be most feasible and further assessments took place. On 14 July 2022 a first meeting took place, where the Heat Highway project was presented. On 26 January 2023, a meeting took place in which the use case ‘Ennshafen’ business models for the use of industrial waste heat for external process heat were presented. Possible barriers were identified, success factors presented and the project group defined (specific companies as supplier, operator and customers as well as the constructing company). The individual situations of the companies were presented in order to create a basis for discussion. The project was clearly illustrated with examples. A total of 14 people from 6 companies from the Ennshafen area were present at the meeting. This use case has made a significant contribution to business model development in WP3. The business model has benefited significantly as a result. 2.6 Use Case #3: HTN Styria The investigation of Styria was conducted in three key phases: a preliminary study, a main study, and a detailed study, all adhering to the standards of a techno-economic evaluation. The preliminary study focused on gathering relevant data and background information, as well as analysing the fundamental components required for developing a supra-regional district heating network. In the main study, both the technical and economic feasibility of the project were thoroughly examined. Finally, in the detailed study, the economic viability was further scrutinised, with a closer focus on critical influencing factors. The methodology used for the analysis in the preliminary study and the technical analysis in the main study is detailed in Steinegger et al. (2024) 39 . Similarly, the approach for conducting the economic analysis in the main study, as well as the detailed study, is outlined in Steinegger et al. (2025) 40 . A comprehensive summary of these topics, along with additional results, can be found in Steinegger (2024) 41 . 39 Steinegger (2024). Revolutionizing heat distribution: A method for harnessing industrial waste. heat with supra-regional district heating networks, doi.org/10.1016/j.apenergy.2024.123769. 40 Steinegger (2025) Assessing the Technical and Economic Feasibility of Supra-Regional District Heating Networks. currently under review. 41 Steinegger (2024). Supra-Regional District Heating Networks: Harnessing Industrial Waste Heat for a CarbonFree Heat Future, Current under review. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 64 of 91 Company Municipa lity Currentl y supplie s a DH Network Main Processes Prognosis improves, the waste heat availability might decrease further. Tyrolit Schleifmittel Schwaz Schwaz No Mechanical processes Waste heat is limited since most of Tyrolit’s mechanical processes are not high-temperature. Unless there are auxiliary systems like cooling that generate recoverable heat, the potential is low. Sandoz Schaftenau Schaften au No Electricity, steam generation; waste heat: drying equipment, compressed air compressors Steam generation by heat pump may reduce waste heat availability. 2.7.1.2 Basic Routing A basic routing of the HTN was derived, based on the existing HTN between Innsbruck and Wattens in the western part of the inn Valley, which follows the Inn valley highway (see Figure 20). The proposed HTN will also follow the Inn Valley highway, supplying all 32 municipalities along the way. For this purpose, existing district heating distribution networks and municipalities without networks, where it would have to be built, were taken into consideration. The preliminary route is shown in Figure 20 and depicts a total of approximately 82 km of heating pipeline from Wattens to Kufstein and to Fügen in the Ziller Valley. Approximately 34 km pass through urban areas, while 48 km pass through rural, unpaved terrain. Figure 20: Proposed routing of the HTN in the eastern Inntal FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 65 of 91 2.7.1.3 Techno-economic feasibility evaluation More details can be found in Marx et al. (2023) 47 . To model and mitigate economic risks, a Monte Carlo simulation was used, analysing 10,000 scenarios with varying energy costs and waste heat availability and compares a maximum configuration where close to 90% of the heating demand in the municipalities is provided by the HTN, including the construction of new supply networks, to an individual configuration, where the existing district heating network remains unchanged. For individual heating systems, specific decarbonization pathways for heat supply to municipalities and regions at the building level were considered (shifting fossil fuel demand to decarbonized alternatives). The simulation considers fluctuations in energy prices for electricity, biomass, and waste heat, as well as potential shifts in waste heat supply. This probabilistic approach allowed for evaluating the network’s levelized cost of heat (LCOH) and economic resilience under diverse conditions. Key findings from the simulation indicate that diversified heat sources, such as industrial waste heat, CHP, and biomass, provide a stable economic basis for the HTN. Flexible pricing mechanisms, such as a heat merit order (HMO), enable prioritized use of cost-effective sources, maximizing economic efficiency and reducing vulnerability to individual prices spikes. Key cost components, besides the HTN and the construction and enlargement of the distribution networks, include heat supply units, such as combined heat and power (CHP) plants and heat pumps, along with storage facilities to support peak demand and ensure operational flexibility. Operational expenditures (OPEX) account for maintenance, auxiliary energy, waste heat costs, and network expansion, reflecting a balanced financial structure to sustain long-term network viability. General cost assumptions based on local information and databases were the basis for the individual heat supply. Comparatively, the HTN model demonstrated a lower economic risk than individual heating systems, with LCOH variability of +/-4% versus +/-9% in individual configurations. This is due to the HTN’s ability to optimize lower-cost waste heat and deploy heat pumps at low electricity prices, as well as CHP units at higher electricity prices, to manage costs effectively. The result is a more stable, resilient heat supply network that reduces reliance on volatile energy sources, offering substantial risk reduction and economic sustainability over isolated heating systems. 47 Marx, Blakcori, Forster, Maggauer, Schmidt (2023). Risk assessment in district heating: Evaluating the economic risks of inter-regional heat transfer networks with regards to uncertainties of energy prices and waste heat availability using Monte Carlo simulations. Smart Energy, Volume 12, November 2023, 100119, https://doi.org/10.1016/j.segy.2023.100119. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 66 of 91 Figure 21: Comparison of the LCOH for the HTN and the individual configuration at different waste heat prices 2.7.1.4 Heat Highway WebApp 48 To also compare possible configurations for different district heating demands, modelled with the district heating potential economic assessment, and energy price scenarios, an optimiser 49 was used to decide on the optimal supply infrastructure in the HTN Inntal, based on existing infrastructure, local potentials, energy prices, CAPEX and OPEX. Results were visualized in a web application (https://ies-apps.ait.ac.at/hhw) for different district heating demands and energy price scenarios. Figure 22 below outlines the possibilities for the optimiser for the district heating supply. The town or municipality represents the overall heating demand, including residential and service sector demand. Supply elements can include: • Biomass CHPs • Waste heat sources • Storages • Large heat pumps • Biomass boilers • Connections to other towns and municipalities 48 https://ies-apps.ait.ac.at/hhw (Abgerufen am: 17.12.2024) 49 https://github.com/ait-energy/iesopt (Abgerufen am: 17.12.2024) FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 67 of 91 Figure 22: Potential heat supply setup 2.7.1.5 Business & Action Plan The implementation of the HTN Inntal depends on a multi-faceted approach including funding, stakeholder engagement and a clear action plan. More information can be found in the deliverable “Heat Highway - Follower Inntal (Business Case)”. 2.7.1.5.1 Financing Strategy The financing will combine debt capital from banks, private investors, and national and European subsidies. Notable funding sources include the Climate and Energy Fund (KLIEN), the Umweltförderung managed by Kommunalkredit Public Consulting (KPC), and European programs like Horizon. Current funding schemes focus on capital expenditures (CAPEX) while offering limited support for operational expenditures (OPEX). A detailed review of available funding options is essential during advanced planning stages to ensure financial stability and sufficient capital for network expansion. 2.7.1.5.2 Stakeholder Engagement Engaging local stakeholders is crucial for the successful implementation of the HTN. This includes conducting consultations to align the project's objectives with community needs and securing commitments from industrial players to supply waste heat. The development of a collaborative business model involving operational stakeholders will help identify cost benchmarks and financing options. 2.7.1.5.3 Action Plan Possible next steps for the implementation of the HTN Inntal are listed below: FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 68 of 91 • Market Analysis and Feasibility Study: Conduct a detailed feasibility study to validate demand and supply data. The initial findings should guide further investigations into untapped waste heat sources and existing infrastructure. • Technical Planning: Finalize the optimal routing of the HTN using GIS analysis to identify suitable locations and ensure compliance with environmental regulations, including necessary permits. • Securing Financing: Intensively pursue funding from identified sources, emphasizing the establishment of clear collateral and payment structures to attract investors. • Construction Phase: Execute the construction plan, ensuring the installation of pipes and auxiliary components, followed by rigorous testing to guarantee operational reliability. • Commissioning and Start-Up: Upon successful commissioning, coordinate activities with local district heating networks to facilitate integration and optimize operating conditions. By implementing these steps, the Inntal HTN aims to provide a reliable, climate-friendly heat supply to the region while fostering economic sustainability and community involvement. 2.7.1.6 Conclusion The success of the existing heat transfer network (HTN) between Innsbruck and Wattens in the Inn Valley, Tyrol, has highlighted the potential of such systems. Consequently, several regional stakeholders are exploring ways to expand this concept throughout other parts of the Inntal, potentially achieving a continuous connection from Kufstein to Wattens. This expansion would allow for the utilization of otherwise unused waste heat, improve the reliability of heat supply, and open new economic opportunities for industrial companies in the region. 2.8 Follower Case #2: HTN Innviertel As part of work package 7, task 7-2 “Follower case HTN Innviertel”, a concept, inspired by the method of a business model plan, was developed for the implementation of a potential heat transmission network (HTN) in the Innviertel region in Upper Austria. The concept aligns with the structure of a business model plan where applicable. A summary of the approach is provided below. The full report is available online. 50 Further information can be found in the deliverable for Task 7.2 (see “Innviertel” in chapter 6 Appendix). The necessary steps and measures required to implement a HTN for the Innviertel region were outlined. The follower case HTN Innviertel is a conceptual HTN, which interconnects many industrial waste heat and other sustainable sources, district heating networks, and industrial process heat sinks. A presentation of the product, analysis of the market, marketing strategies, 50 Jauschnik, Rodin, Moser (2024) Heat Transmission Network „Innviertel“, Projekt Heat Highway, Task 7.2 Concept and Business Model. Final Task Report, August 2024. Available https://energieinstitut-linz.at/wpcontent/uploads/2023/04/Business-Model-Plan-HTN-Innviertel.pdf (2024-12-09). FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 69 of 91 financial forecasts (with a focus on the capital expenditures) economic estimates and plans for implementation have been made. First, a comprehensive analysis of the potential for implementing an HTN was carried out, including the identification of waste heat sources and potential heat sinks through the utilisation of both existing open data sources and first-hand information obtained from district heating operators and industrial companies. The Innviertel region, especially Ried im Innkreis and the municipalities in its North, is home to approx. 28,500 people, various industrial companies, commercial business and public entities. Furthermore, some municipalities already have district heating networks available, which could be connected in a HTN. These already implemented heating networks can be found in Mehrnbach, Ried im Innkreis, Tumeltsham, Utzenaich, St. Martin im Innkreis and Reichersberg. On the other hand, individual heating systems are still a common choice, e.g. based on oil and gas heaters but also biomass. The total energy consumption in the Innviertel region amounts to 1.07 TWh/year, of which almost 35 % is accounted for by the industrial and commercial sector and 26 % by the residential sector. The remaining energy consumption is split between the mobility (22 %), services (14 %) and agriculture and forestry (2 %) sectors. The heat demand has a share of about 36 % of the total energy demand, with households accounting for 22 % alone and 5 % by industry. Figure 23: Heat demand of agriculture/forestry, industry and living in the different municipalities of the Innviertel region in 2019. Order of municipalities: North to South. Data source: Abart-Heriszt und Erker 2019, Datensatz Energiemosaik Austria. In addition, there are numerous companies in the region that could represent further potential heat sources and sinks for the HTN (listed in the Appendix of the report). These include companies in the food, composite, wood, stone and ceramics, metal and chemical industries, among others. From this assessment, a preliminary pipe routing plan from South to North was developed. The main route of the HTN is planned to connect Ried/Innkreis, Aurolzmünster (optional), St. 0 20 000 40 000 60 000 80 000 100 000 120 000 140 000 Heat demand [MWh/year] heat demand agriculture / forestry (MWh / a) heat demand industry / trade (MWh / a) heat demand living (MWh / a) FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 70 of 91 Martin/Innkreis, Ort/Innkreis, Reichersberg and Antiesenhofen. In the South-West of Ried/Innkreis, a connection to Mehrnbach is also an option to be discussed as the geothermal source of the Ried/Innkreis DHN is in the Mehrnbach area, as regarding population Mehrnbach is in the top three of the eleven municipalities. The areas of Eitzing and Senftenbach are less populated, however, in Senftenbach a brick factory as well as the geothermal source of the DHN St. Martin are located. Thus, the main piping route ideally follows the B141 from Mehrnbach to Ried/Innkreis, then the B143 from Ried/Innkreis to Ort/Innkreis, followed by A8 and/or L522 to Antiesenhofen. The preliminary route is shown in Figure 24 and depicts a total of approximately 50 km in one direction of heating pipelines from Ried im Innkreis to Antiesenhofen. The existing main heating network in Ried extends approximately 13.5 km (blue), while the connection to Mehrnbach is just over 2 km (green). The main pipelines of the St. Martin DHN span about 8 km (purple). The new pipelines to be constructed (indicated in orange) will add a length of just over 27 km. All lengths are indicated in one direction only. Figure 24: Proposed route of the HTN Innviertel. Source: Energieinstitut an der JKU Linz. The capital requirements for a new HTN include a variety of large, long-term and up-front costs, and need to be carefully planned and calculated. Key CAPEX includes investments in the three system parts: heat generation facilities, distribution system including pipelines and substations, and installations at the consumer side. In addition, costs for setting up the company, including legal and administrative expenses as well as regulatory and administrative costs associated with complying with legal regulations and official requirements must also be included in the overall calculation. Detailed and careful planning of these capital requirements FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 71 of 91 ensures that all financial aspects of the project are covered and potential risks are minimized. The length of the new heating pipeline to be constructed is approximately 27 km (one way) with an assumed DN 300 at a base cost of 350 € per meter (one way). The cost for the pipeline itself excludes additional expenses such as installation, permits, and other relevant work. As a result, according to DH experts the actual cost per meter is likely to be two to three times higher when considering all associated factors. A subsequent capital expenditure assessment was carried out to evaluate the feasibility of the proposed HTN in the follower region and resulted in investment cost for simple supply and return pipelines of around 19 million €, based on expert opinions. This estimation will need to be adjusted to account for the specific conditions and requirements of the project. The concept was presented to local stakeholders. Table 9: SWOT-Analysis for the HTN Innviertel. Strengths Opportunities Integration and combination of various sustainable energy sources Rising demand for climate-friendly district heating Increased flexibility, and thus, reliability and sustainability of the network Financial incentives from the government to facilitate implementation of district heating Use of currently unused but abundant resources such as waste heat from local industry, making optimal use of existing energy resources and reducing environmental impact Possibility of building a new DHN in Aurolzmünster (municipality in the north of the Innviertel region) in parallel to the HTN development Contribution to achieving climate targets due to increased renewable (geothermal, biomass, solar) and waste heat utilization Expanded use of the region's geothermal potential and high levels of solar radiation to integrate sustainable and renewable heat sources in the HTN Reducing dependence on fossil fuels, such as gas and oil based individual heating systems Bringing various stakeholders together in the HTN development and operation creates local value and win-win situations. Weaknesses Threats High investment costs in the network infrastructure and the associated technology The long-term planning horizons of DH projects could be jeopardized by changing factors such as political or economic conditions Increased complexity of network management in terms of technical and organizational aspects Changes in regulatory framework conditions Currently, there is no existing DHN in Aurolzmünster, leading to long distances between Ried and St. Martin. This could lead to high transport losses and low acceptance by third parties with no access on the route Discordance of stakeholders DHNs are long-term investments, which require careful planning and securing financing Deteriorating competitiveness due to new, innovative or alternative (individual heating) technologies FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 72 of 91 The connection of existing DHN via the HTN might lead to technical challenges (direct/indirect connection, temperature and pressure levels, water quality) Decreasing heating demand Further, a SWOT-analysis was carried out. The risks of an HTN can be reduced by including many supply and demand nodes, leading to increased flexibility and reliability of the network, as a large number of sustainable energy sources can be used in the event of supply failure by a single source or planned shutdown. Thus, a more robust and reliable heat supply for consumers is enabled. Finally, a preliminary implementation plan for the HTN Innviertel was created, offering a recommended roadmap for the implementation process. The plan outlines the following key steps: conducting a market analysis and feasibility study, developing a business model, carrying out technical planning, navigating the authorization process, securing financing, moving into the construction phase, commissioning, start-up, and ultimately the official opening. 2.9 Follower potentials 2.9.1.1 Description of the Case Study / Region Task 7.3 aims to identify and analyse the waste heat potentials in the regions of Southern Vienna and St. Pölten – Krems, focusing on energy-intensive companies where waste heat, a byproduct of industrial processes, often goes unused. The study's objective is to comprehensively quantify this waste heat potential and identify local heat sinks. Special attention is given to energy-intensive companies to gather precise data on the type and amount of waste heat produced and its potential uses. Direct contact with companies ensures an accurate information collection, providing detailed insights and a solid basis for future waste heat utilization decisions in these regions. Further information can be found in the deliverable for Task 7.3 (see chapter 6 Appendix). 2.9.1.2 Methodology & Data Basis The research began with a comprehensive literature review to standardize the definition and understanding of waste heat across various industrial sectors, such as steel, aluminium, chemicals, textiles, and food production. Next, an industrial map of Lower Austria was used to identify companies that might generate waste heat, highlighting locations with a high concentration of industrial enterprises. Each identified company was thoroughly analysed to assess its waste heat potential based on its industry, size, and activities. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 73 of 91 After identifying relevant companies, contact was initiated through emails and phone calls, including a customized Excel questionnaire to gather data on their waste heat potential. Due to low response rates, the Austrian Heat Map was used as an alternative to estimate waste heat potentials for power plants, district heating networks, and industrial sites, using 2019 data. In addition, research was conducted on potential heat sinks, such as large energy consumers (e.g., commercial buildings and institutions). Where data was unavailable, estimates were made based on building size from online atlases. The heating energy performance indicator was used to estimate energy demand, calculated by multiplying the building's floor area by energy performance indicators. This helped in planning efficient heating systems and integrating waste heat recovery solutions. 2.9.1.3 Results 2.9.1.3.1 Contact Initiation Upon contacting companies by phone, it became evident that staff at general telephone switchboards often hesitated to provide the contact details of responsible personnel. They typically requested a brief project description to be sent to the office email address. In rare cases, direct contact with a responsible person was established, enabling the exchange of contact details and transmission of informational material and distribution of the questionnaire. Despite these efforts, both direct telephone acquisition and email outreach resulted in an insufficient response rate regarding waste heat potential information. Only a limited number of companies responded with follow-up questions or completed questionnaires. Possible reasons for the low response rate include company distrust towards consulting firms and limited time resources. 2.9.1.3.2 Waste Heat Potentials Due to insufficient direct data collection, waste heat potentials were evaluated using heat map research. Waste Heat Potential in the Southern Vienna Region: Heat map research identified several companies with waste heat potential, categorized into three levels: below 50°C, between 50°C and 100°C, and above 100°C. The identified waste heat potentials are as follow: • Waste heat potential < 50°C: 111 GWh/a • Waste heat potential 50°C – 100°C: 10 GWh/a • Waste heat potential > 100°C: 5.5 GWh/a Figure 25 displays the precise locations and temperature levels of the waste heat potentials using Power Map in Excel. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 80 of 91 students, but often also teachers on further education programmes or members of NGOs or educational initiatives. 3.2.1.1 Methods of presentation • Area mediation: Info trainer colleagues convey the content of the exhibition in dialogue as required. All colleagues were trained in September 2022 and given a "study hour" to learn the content. • Highlight tour: Heat Highway is often a favourite stop on guided tours as a representative station for the "There is no Planet B" area. • Planet B themed tour: Heat Highway is an integral part of the themed tour. Industrial waste heat utilisation is presented as part of the energy transition and as a link to circular economy. • Teacher training programmes: The Heat Highway project is discussed intensively in teacher training courses on climate and energy topics. • Heat Highway on the website: Heat Highway is made available on the website in the exhibitions section, including an animation of the virtual demonstrator (AE Solutions) and images of the physical demonstrator. https://ars.electronica.art/center/de/heat-highway/ • Heat Highway video shoot: A video was produced as an internal training video. It provides a compact and comprehensible explanation. More detailed information is supplemented by written documents. Showing complexity, price levels, ecological footprint of different sources of waste heat, the important players, the infrastructure/network and the heatsinks and suppliers at different situations around the year with summer season, winter season and spring/fall season. A suitable screen was purchased for the virtual demonstrator, as the project was added to an existing exhibition. The headphones and platform for the screen come from the existing inventory. For the pipe-demonstrator LED lights, power sources and additional material was purchased. 3.2.1.2 Virtual demonstrator The following scenarios were developed, incorporating considerations for summer, winter, and spring/fall seasons, both with and without HHW integration: 3.2.1.2.1 Scenario Summer: • Existing HHW: The total heat demand in summer is the lowest, although the heat demand of the industry is rather constant over the year. Only the must-run waste incineration plant is in operation for heat supply. Companies feed waste heat into the HHW and thus support the heat supply. A seasonal storage is integrated to store excess heat. The average CO2 footprint and marginal costs are the lowest. • No-built HHW: Although the total heat demand is at its lowest, combined heat and power plants (gas, biomass) have to support the heat supply to cover peak demands. Reason: FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 81 of 91 There is no HHW and thus companies can only partially feed waste heat into the local grid or not at all. This results in an unused waste heat potential and to an increase in the average CO2 footprint and marginal costs. Figure 31: AEC Demo Heat Highway Summer Scenario existing Heat Highway 3.2.1.2.2 Scenario Transition: • Existing HHW: Due to an increase in the heat demand of households, a medium heat demand exists. Whereas the must-run waste incineration plants are still in operation, companies providing waste heat and biomass fired combined heat and power plants are necessary to cover peak demands. The seasonal storage either supports in covering the peak demands or stores available excess heat. The average CO2 footprint and marginal costs are on a medium level. • No-built HHW: Without the HHW, an additional operation of the gas fired combined heat and power plant is required to cover the heat demand. This results in an increase of the average CO2 footprint and marginal costs. In addition, an unused waste heat potential occurs, which could otherwise be integrated into the HHW. Compared to the HHW connection, the average CO2 footprint and marginal costs become worse. 3.2.1.2.3 Scenario Winter: • Existing HHW: The highest heat demand occurs in winter (sum from households and industry). Waste incineration, combined heat and power (gas, biomass), and industrial waste heat are necessary to cover the heat demand. The stored excess heat from the summer can be utilized now to support the heat supply. This results in a positive effect of the average CO2 footprint and marginal costs. • No-built HHW: Due to the highest heat demand in winter and the non-built HHW, the average CO2 footprint of the heat supply is intense and costs are expensive. Companies can only partly feed into the local grid and an unused waste heat potential exists. FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 82 of 91 3.2.1.3 Prototype A physical "Heat Highway" prototype was developed and constructed, incorporating the technical characteristics and requirements discussed. The prototype was exhibited at the at the Ars Electronica Center (AEC) in Linz. This prototype, in combination with a developed virtual demonstrator, showcases cutting-edge thermal energy technology and engineering innovation, offering visitors an engaging and interactive experience. Designed with key characteristics in mind, the prototype aligns with exhibition standards to effectively communicate the basic principles of sustainable district heating and raise awareness of heat supply. Its design enables visitors to easily comprehend the core concepts of sustainable district heating, emphasizing its critical role in modern energy systems and its potential to reduce environmental impacts. The prototype integrates the fields of energy engineering, research, and exhibition design, providing visitors with an optimal learning experience. This collaborative effort ensures that the prototype is both informative and accessible, making complex engineering concepts easy to understand and relatable for a broad audience. In preparation for the design, construction, and installation of the demonstrator by Kremsmüller, it is crucial to establish the necessary framework conditions in collaboration with the AEC. The plan was to integrate the prototype into the “There is no planet B” exhibition. The following conditions were considered and discussed: positioning options, space requirements, dimensions, environmental considerations, logistics and accessibility, safety and compliance, integration with AEC infrastructure and visualization. This collaborative effort helped to determine the optimal location and setup for the demonstrator, ensuring it meets both practical and aesthetic requirements. Based on the developed variants, two demonstrators were finally built, which also optimally fit in the exhibition "There is No Planet B." FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 83 of 91 Figure 32: Demonstrator I at the AEC exhibition The demonstrator itself includes several key components to illustrate the project concept: • Main heat transfer pipe (Heat Highway): This serves as the primary pipe for transferring heat. • Feed-in of industrial waste heat: This demonstrates how industrial waste heat is fed into the system. • Provision of process heat: This section shows how the system provides heat for various industrial processes. • Section of heat transfer pipe structure: A cross-sectional view of the pipe structure to explain its construction and functionality (pipe and insulation). • Feed into the district heating network: This illustrates how heat is ultimately distributed into the district heating network. 3.2.2 Stakeholder participation & local involvement, Dissemination & international visibility 3.2.2.1 Stakeholder participation & local involvement Three workshops were conducted by partner BIZ, with a total of 69 participants. 3.2.2.1.1 1st Heat Highway Workshop “Waste heat” at Business Upper Austria, 14.07.22 The main objectives of the workshop were to introduce the Heat Highway project, discuss the possibilities and challenges of industrial waste heat utilization, and provide a platform for experts and stakeholders to exchange ideas and experiences. The workshop aimed to bring together industry, academia, and policy-makers to facilitate collaboration and knowledgesharing on the topic. The first session of the workshop focused on the theoretical and practical FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 84 of 91 aspects of operational-external use of industrial waste heat and the use of high-temperature steam-producing heat pumps for reusing waste heat in other companies. The second session was dedicated to practical examples of industrial waste heat utilization. After the expert-input presentations, the workshop provided a platform for discussions and exchange of ideas. The Heat Highway Workshop was a successful event that brought together experts and stakeholders from various fields and facilitated knowledge-sharing and collaboration among the participants. The discussions helped to identify potential solutions to the existing challenges and opportunities for further collaboration in this important area. The workshop was an excellent platform for networking and collaboration and helped to advance the goals of the Heat Highway project. 3.2.2.1.2 2nd Heat Highway Workshop “Summer sinks” at Business Upper Austria, 25.01.23 In this workshop new insights into possible approaches in seasonal heat storage and usage were shown, namely summer sinks. It provided a platform for experts and stakeholders to exchange ideas and experiences. The workshop aimed to bring together industry, academia, and policy-makers to facilitate collaboration and knowledge-sharing on the topic, as well as the input of new expert knowledge into the consortium. After the expert-input presentations (on excess heat in summer, seasonal storage, waste heat for process heat, new and innovative concepts with absorption chillers, local heating networks as heat sinks in summer) the workshop provided a platform for discussions and exchange of ideas. The presentations brought new insights (feedback was great) to all participants and a lot of networking was done after the workshop. 3.2.2.1.3 3rd Heat Highway Workshop at Business Upper Austria, 25.06.2024 The main objectives of the event were to present the results of the project and to bring all workshop participants up to the same level of knowledge. Additionally, the projects “Lessons learned” were collected, which provide valuable insights into which waste heat potentials could already be utilised technically and economically in the opinion of the companies and where there is still a need for further research and development The expert event of the Ars Electronica Center "Economic efficiency of energy storage" held on 19.03.24, aimed to provide a platform for different energy storage areas to express their views, explain established and expected business models, present the economic viability in terms of costs and benefits, and discuss the requirements for economic establishment. During the event, the stakeholders also examined the demonstrator. 3.2.2.2 Dissemination & international visibility 3.2.2.2.1 DHC+ Summer School From 25 to 30 August 2024, the 12th edition of the DHC+ summer school took place in Linz, focusing on "Industrial urban symbiosis as an enabler for climate-neutral district heating." The summer school was organised by Euroheat & Power in collaboration with the Energieinstitut an der JKU Linz. The event was designed to raise awareness of the main topic and make it FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 85 of 91 more approachable for participants. This year's edition brought together 40 participants from 21 countries and 33 different organisations. Throughout the immersive week, attendees gained valuable insights into the district heating and cooling sector, networked with peers, and learned from leading industry professionals and academics. The program encouraged collaboration and innovation, with lectures and workshops led by experts from DHC+ platform member organisations and Austrian partners. The presentations covered a wide range of topics, starting with an introduction to district heating and cooling (DHC) including the current DHC situation in Austria. Further, relevant EU legislation and policy, industrial waste heat recovery, sector coupling and business models were presented. In addition, the lectures covered financing instruments, district cooling engineering, efforts to decarbonise DH systems, insights into the Austrian Heat Map, and the implementation of large-scale thermal energy storage solutions. The summer school highlighted the project Heat Highway. In addition to the presentation by our experts on industrial waste heat recovery from existing and future processes, participants visited the Ars Electronica Center, the "museum of the future," to explore the Heat Highway virtual demonstrator and view the prototype first-hand. 3.2.2.2.2 International Workshop The online workshop "Heat Highway: Using Decarbonised Heat Sources via Supra-Regional Heat Networks" online workshop on 3rd March 2023 organised in the context of the international conference World Sustainable Energy Days ensured a wide dissemination of the project topics and international visibility. The workshop was attended by more than 50 participants and dedicated to the exchange of experiences with interregional heating networks in Europe. International speakers from Denmark (example Copenhagen) and the DHC+ Platform (Euroheat and Power) were part of the programme, thus contributing to the international visibility of the project. 3.2.2.2.3 International Conference Being part of the NEFI network offered manifold dissemination and networking opportunities at NEFI events (e.g. NEFI Technology Talks, Workshop 19th March 24). Especially the second international NEFI conference (13th-14th Oct. 2022, Linz), in which parallel sessions and workshops were included (e.g. IEA IETS Task 19 workshop), presented a unique opportunity for exchange and networking. The Energy Institute at the JKU and the AIT delivered presentations at the international Smart Energy Systems Conference 2023 in Copenhagen on the topic "How can industrial waste heat be used in district heating networks? Insights on effective project initiation and business models." and on the topic “Heat transmission network design optimization and robustness analysis for a case study in Tyrol – Methodology” The conference aims to serve as a platform for presenting and discussing both scientific findings and industrial experiences related to Smart Energy Systems. Over the years, it has evolved into a primary venue for impactful FTI Initiative Energy Model Region - 3. Call for Projects Fede r al Climat e and E nergy Fund – Ha ndl ing b y T h e A ustr i an Re sea rch P romoti on Agency FFG Page 86 of 91 presentations and stimulating discussions on the development and implementation of smart energy systems to meet national and international objectives. 3.2.2.2.4 International Seminar The AIT held a seminar “Séminaire Énergie - Environement” at the Université de Genève in March 2023 about “Risk minimization for decarbonizing heating networks via network temperature reductions: opportunities and challenges, Experience from Austria and outlook”. The seminar was for employees and students from the Université de Genève. 3.2.2.2.5 Additional dissemination & broad visibility • Peer-reviewed scientific papers • Scientific papers under review • Doctoral thesis, master thesis, 6 bachelor theses • Conference papers or posters • Workshops, and presentations • Award for innovation from the regional government of Upper Austria • Broad visibility showcasing of the virtual demonstrator at the ARS Electronica Museum of future (guided tours, 1000s visitors (national & international) - visibility for the general public) 4 Outlook and recommendations In particular, the following recommendations should be made for further research: • Tools for the initial determination of techno-economic feasibility • Tools for more detailed technical analysis • Tools for detailed economic analysis • Models for the description of the regional market including heat price and remuneration for reserve capacity FTI Initiative Energy Model Region - 3. 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