Heat networks for a more sustainable heat supply

Increased use of renewable energies through district heating

District heating plays a major role in the energy transition. Compared to decentralized heating systems, centralized heat generation in conjunction with a heat network enables the integration of renewable heat sources and is a cost-effective alternative, especially in densely populated urban areas. Planning and expanding of the piped heat supply is therefore essential for the energy transition.

The heating sector is energy-intensive and a key factor in achieving climate protection targets. Piped heat supplies have numerous advantages that are necessary for a sustainable heat supply. They enable increased efficiency and greater use of renewable energy sources in heat supply, thus contributing to reducing CO2 emissions or achieving climate neutrality.

The advantages of district heating networks include:

  • Utilization of waste heat potentials (industry, waste water) and combined heat and power generation
  • Large-scale integration of natural heat sources, e.g. through (large-scale) heat pumps (air, geothermal, water)
  • Efficient heat supply in high-density regions with low space requirements
  • Easy step-by-step conversion to renewable energy sources with lower investment costs
  • Support of sector coupling through storage potentials

Establishing efficient heating networks with the help of potential analyses

To ensure the economic operation of heating networks, planning is enormously important with regard to investment and operating costs. The number of connections as well as the possible sales volume in relation to the necessary pipeline expansion in the supply area are decisive factors. In view of the current restructuring of the heating market, potential analyses are of immense importance. Fraunhofer IFAM with a comprehensive range of services at the smallscale level using geographic information systems, such as inventory and potential analyses, calculations of heat production costs, definitions of priority areas, and the development of a target scenario for climate neutrality.

These analyses meet the requirements of district heat planning. Researchers transfer the findings from the analyses are into a heat transition strategy and derive recommendations. They provide competent support throughout, from the analysis of the existing situation to the development of the heat transition strategy.

Our experts support the path to a more sustainable and forward-looking heat supply by taking a holistic view of the potential of expanding or building new piped heat supply systems and integrating renewable heat sources.

Innovative ceiling elements improve dynamics of surface heating systems

In the Hybrid-FHKL project, a new type of surface heating and cooling system was developed, which also performs air conditioning functions. By using cellular metallic structures, the temperature ripple at the surface could be significantly improved. Integrated ventilation channels allow fresh air to be locally preconditioned for the space to meet global and local comfort criteria. Researchers built and evaluated demonstrators using numerical simulations and experimental investigations. They provided functional proof of the hybrid element was provided, and it and classified it energetically to existing systems. In the requested follow-up project Hybrid-FHKLPraxis, the hybrid elements will be subjected to a field test under real conditions, which will take place at the Fraunhofer IFAM in Dresden. The field test will provide reliable information on the system integration of the element and its influence on the indoor climate based on assessments by the room users.