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Upgrading the performance of district heating networks in Europe

Periodic Reporting for period 2 - Upgrade DH (Upgrading the performance of district heating networks in Europe)

Reporting period: 2019-11-01 to 2021-09-30

According to the EU Strategy on Heating and Cooling (2016), the contribution of district heating (DH) in the EU accounts for 12% of the total final heating and cooling energy consumption. Furthermore, it is highly concentrated in a few Member States and only a limited share of DH networks is highly efficient and based on renewables. However, district heating networks present a high potential for the transition of the heat sector, both technically and organizationally. They are able to integrate efficiently biomass and other renewable energies and they could facilitate sector coupling (coupling between heating, electricity and mobility).
In order to use this potential, many district heating networks must first upgrade the existing distribution system, including the substations and consumer connections: reaching lower leakage rates and heat losses, reducing operation temperatures, adapting piping dimensions and hydraulic, introducing modern IT-based management systems and options for user control. This makes the heat distribution more efficient, but also improves the efficiency of the heat generation. Moreover, DH systems allow the integration of biomass, other renewable energies, excess and waste heat. In order to have an optimized impact, the retrofitting measures should therefore begin with the retrofitting of the distribution network, including measures regarding substations and heating system of the connected buildings. In a further step, efficiency measures can be implemented on the generation side and the share of renewable and waste heat can be introduced and increased gradually. This must go hand-in-hand with predictions of future heat demand as well as with efficiency measures on the end use of heat.
The EU project Upgrade DH (H2020; Contract No. 785014; supported the upgrading and retrofitting process of DH systems in different climate regions of Europe, covering various countries. The target countries of the Upgrade DH project were Bosnia-Herzegovina, Denmark, Croatia, Germany, Italy, Lithuania, Poland, and The Netherlands. In each of the target countries, the upgrading process was initiated for concrete DH systems of the so-called Upgrade DH demonstration cases (demo cases). The gained knowledge and experiences were replicated to other European countries and DH systems to leverage the impact.
Core activities of the Upgrade DH project included the collection of the best upgrading measures and tools, the support of the upgrading process for selected district heating networks, the organisation of capacity building measures about DH upgrading, financing and business models, as well as the development of national and regional action plans. In addition, an image raising campaign for modern DH networks was carried out in the Upgrade DH project.
In conclusion, the Upgrade DH project was very successful as it surpassed the foreseen impacts as shown below. A highlight is that several of the upgrading measures were already implemented during the lifetime of the project, which was not expected. This shows the high need and value to upgrade DH systems.
The Upgrade DH project was implemented from 1 May 2018 to 30 September 2021 (41 months). The following work has been performed and the following results have been achieved:

- 16 Best Practice (BP) examples on project which have undergone already an upgrading process have been collected and described.
- A “Catalogue on “Best practice instruments and tools to diagnosing and retrofitting inefficient networks” was elaborated and includes descriptions of tools that can be used for calculations, modelling, planning, mapping and decision-making. The document contains 12 software-based tools and 4 instruments.
- Several study tours and site visits have been organised for project partners and stakeholders to best practice examples and demo cases. Approximately 150 participants attended these events in total.
- A handbook on “Upgrading the performance of district heating networks - Technical and non-technical approaches” was elaborated and is available in 6 languages. The contents have been communicated and are already used as a basis in another European research projects (LowTemp). The handbook was printed and is widely disseminated.
- A guideline on successful business models and financing schemes for upgrading DH networks has been elaborated and is available on the webpage.
- In each target country, working groups have been set up consisting of local stakeholders of the Upgrade DH demo cases in order to help identify and discuss about the upgrading measures and processes.
- For each Upgrade DH demo case, a global assessment and diagnosis of the current status of the DH system was made. Various upgrading measures were identified, and their feasibility was checked. Business models for each upgrading measure were elaborated. Several upgrading measures are already implemented, which is a big success.
- 8 replication cases with most promising upgrading potentials have been identified and supported with expertise from the Upgrade DH consortium.
- Many dissemination activities were made to raise awareness among the different stakeholders and to promote the project.
- A public image raising campaign was implemented to increase the public awareness and to improve the perception of DH. The campaign was very successful as more than 50,000 citizens were reached.
- Eight national action plans for district heating networks development and retrofitting in the Upgrade DH target countries were elaborated. They include an overview of the current policy framework relevant for DH development, market analysis and challenges, as well as proposed solutions.
The expected potential impact categories of the Upgrade DH project are:
- The overall impact of Upgrade DH is significant. The proposed measures for upgrading lead to a reduction of 16.9% of the primary energy demand and 51.9% reduction of greenhouse gases of the DH systems at the eight demo sites. In absolute numbers, this is a reduction of more than 150,000 t of CO2 equivalent per year. Furthermore, the share of using waste heat increased by 3.3% and the share of renewable energies increased by 21.7%. Several of the upgrading measures were already implemented during the lifetime of the project.
- The Upgrade DH project has managed to raise very significant interest at EU level amongst key members of the DHC industry. Whenever abstracts were submitted to important conferences (e.g. Smart Energy Systems Conference, EUBCE, IEA Symposium), they were accepted and presentations showed a high degree of participation and engagement. The potential for replication has repeatedly been highlighted as a key factor to increase impacts in the medium run and the pragmatic and holistic approach regarded by third parties as a key strength of the project.
- The “Upgrade DH” brand became recognised as a best practice itself, which is obviously very beneficial to partners from the consortium to present their services. It is expected that, also due to the synergies that have been initiated with the Celsius Initiative, the capacity of the project to inform and inspire a large fraction of EU utilities undertaking upgrading measures, will live beyond the project’s termination, and so will the established collaboration between many project partners, all with the aim of upgrading district heating systems towards more sustainable ones.
Site visit in Bosnia and Herzegovina
Stakeholder meeting in Ferrara
Project meeting in Lithuania
Project meeting in Denmark
Project interview in Bosnia and Herzegovina
Study tour in Denmark
DHCitizen campaign
Project meeting in Lithuania
Study tour in Denmark
Study tour in Denmark