The lead project for the intelligent and sustainable heat supply of the future

In 2016, Austria's space heating requirement amounted to approx. 87 TWh/a (total energy requirement: 311 TWh/a)1. A quarter of this is provided by grid-connected heat supply through more than 2000 district heating systems.

This means that the local and district heating sector already plays a central role in Austria's energy supply. Around 5,400 kilometres of valuable heat pipe infrastructure have currently been laid in Austria. They pass sewage treatment plants as well as industrial and commercial enterprises whose residual and waste heat could be used in many ways, and on their way there are open spaces on which solar heating systems and heat accumulators could be installed. The already installed infrastructure, the existing expansion potential, especially in dense urban areas, the use of new concepts, technologies and renewable energy sources, the use of opportunities for sector coupling and the resulting contributions to the decarbonisation of our energy system will increase the importance of the sector in the future.

Already today, every fourth house in Austria is supplied via heating networks - the aim of the ThermaFLEX lead project is to make them more flexible. A consistent integration of renewable energies and waste heat into the heating networks of the future would not only improve the air in the cities, but would also avoid considerable CO2 emissions, increase security of supply and protect consumers from rising oil and gas prices in the long term.


This is precisely where the lead project "Thermaflex" comes in, which within the showcase region "GreenEnergyLab" focuses on increasing energy flexibility and the resulting CO2 emission reductions in the district heating sector. At the beginning of the year, the Climate and Energy Fund, financed by funds from the Federal Ministry of Transport, Innovation and Technology, launched the ThermaFLEX lead project to develop such alternative energy sources for heating networks in the future. The aim of the project, which is scheduled to run for four years, is to develop strategies for making heating networks more flexible in order to increase the proportion of CO2-free heat. And this is exactly where ThermaFLEX comes in, which is headed by the Austrian research institute AEE - Institute for Sustainable Technologies (AEE INTEC). In eight work packages, 27 project partners from the energy industry and research as well as technology providers are working on the identification, simulation-supported planning, evaluation and selection as well as the implementation in combination with detailed monitoring and the resulting optimisation of flexibilisation measures. Over the next four years, they will support the implementation of seven demonstration plants for the flexibilisation of heating networks.

Procedure and methodology

In a sustainable and fully decarbonised energy system, e.g. large proportions of renewable, sometimes volatile energy sources, integrated sector coupling, decentralised energy conversion structures, etc. will lead to a considerably increased system complexity. At the same time, however, security of supply must be maintained and energy costs must remain affordable for end customers. This can only be achieved by increasing the flexibility of the overall system, which permits intelligent interaction between technical elements and non-technical elements.

District heating systems are ideally suited for measures to increase flexibility in terms of sector coupling, integration of renewable energy sources, waste heat utilisation, use of heat storage, new operating strategies and user integration. These flexibilisation potentials can be further increased if holistic approaches are pursued and new scientific methods for simulation and optimisation are used in planning, implementation and operation.

Funding and research landscape

ThermaFLEX is the largest project within the "Showcase Region Energy" programme initiated by the Climate and Energy Fund. This programme is to develop and demonstrate model solutions for intelligent, safe and affordable energy and supply systems using innovative energy technologies from Austria. ThermaFLEX is part of the "Green Energy Lab", one of three showcase regions. The other two are New Energy for Industry (NEFI) and Hydrogen Initiative Showcase Region Austria Power & Gas (WIVA P&G). By 2021, the Climate and Energy Fund intends to invest a total of 120 million euros in the overall programme.

In total, the Climate and Energy Fund provides around 8 million euros in funding for the ThermaFLEX research project and the demonstration projects, of which around 5 million euros are for investment promotion and almost 3 million euros for the accompanying research work. The research partners are providing targeted support to the heat network operators in the detailed development of the demonstration plants and systemic integration. The first measures are expected to be implemented at the end of 2019.


The focus is on seven exemplary demonstrators in district heating supply areas of small, medium-sized and large cities. The funding volume for Thermaflex and selected demonstrators amounts to approx. nine million € and makes this project the largest project in terms of the total funding volume in the course of the second call for tenders of the "Model Region Energy" programme.

The processing of the research project Thermaflex is based on the scientific monitoring of the seven selected demonstrators on a systemic level along the entire process from idea and concept development to planning and implementation, commissioning, monitoring as well as evaluation and continuous optimisation.


Theresia Vogel, Managing Director of the Climate and Energy Fund: "Heat networks are excellently suited for the integration of renewable energies and waste heat and enable coupling with other energy sectors or energy infrastructures. In this context, it is important to cushion the differences between generation and consumption through flexible storage capacities and "intelligent control strategies".

Norbert Hofer, Minister of Innovation: "With projects like this, which is being implemented in the Green Energy Lab, we are taking a future-oriented path towards innovative, safe and affordable energy. Only strong alliances between industry and science will make it possible to take this path successfully and thus implement our national climate and energy strategy #mission2030".

Christian Fink, responsible division manager at AEE INTEC: "A wide range of different technical measures and heat sources was important to us when defining the pilot projects, in order to generate the best possible learning effects for transferring the findings to other cities," reports