Energy services for the optimised summer utilization of district heating systems

Development of practicable energy services for the summer utilization of district heating systems with reference to existing technologies to improve the efficiency and potentialities for the integration of renewable energy.

Short Description




The subject and a goal of the project is the development from marketable innovative energy services to the increase of the energy efficiency in existing district heating nets. Focus is the summer use of the district heating net and the improvement of the framework conditions for the feed-in of renewable energies (e.g. decrease of the return flow temperatures of the district heating net).

Energy services such as Contracting are a promising instrument for the increase of energy efficiency. The energy services shall serve as door openers and to overcome existing market barriers for new energy-efficient technologies. In particular Contracting contributes considerably to the market penetration of innovative technologies, as proved by a lot of projects.

Numerous projects with innovative technologies lack the coordination and common optimization of planning, establishment and operation as well as the service aspect, i.e. support and continuous plant optimization during the operation. Furthermore a lot of good projects failed not at least because of the financiability. Elements of energy services especially Contracting are very useful, even if higher investment costs occur through new technologies.

In this project energy services (especially Contracting models) shall be developed on basis of concrete technologies, which improve the summer use of district heating, which increase efficiency of the nets and improve the possibilities for the integration of renewable energies.

On the basis of a market survey (technologies and possible areas of application/groups of customers) an estimation of the market potential takes place. Based on it, market-focused service packages for the following areas are compiled:

  • cooling with district heating
  • optimization for heat transfer stations and heat distribution systems to reduce the return flow temperatures and increase efficiency
  • extension of the district heating use in existing heat supply systems for residential buildings
  • integration of heat pumps into the net structure

Results of the project:

  • market analysis
  • comparison of different technologies
  • areas of application for cooling with district heating
  • optimization potentials of heat transfer stations and heat distribution systems (manual)
  • measures to increase the density of the existing district heating net especially for residential buildings
  • possibilities of the integration of heat pumps into district heating nets
  • custom-made energy services and/or Contracting-models
  • dissemination of the results in form of a Workshop, info material, internet presentation and final report

Project Partners

Project leader

DI Karin Schweyer, Grazer Energieagentur Ges.m.b.H.


Grazer Energieagentur Ges.m.b.H.

Contact address

Grazer Energieagentur Ges.m.b.H
Kaiserfeldgasse 13/1, A - 8010 Graz
Tel.: +43 (0) 316 811848
Fax.: +43 (0) 316 811848 -9
Internet: Grazer Energieagentur

DI Karin Schweyer
DI Gerhard Bucar

Project partners

  • TU Graz, IWT - Arbeitsgruppe Heizung-Kälte-Klimatechnik
  • TB Meißner