Submit Your Proceedings

Thank you for considering to join us with your high-quality scientific content. Note that our service is free for website users as well as organizers/publishers, the rightsholders nor no membership is required.

You can submit all your questions, opinions, suggestions and complaints using the contact form.

Optimal dimensioning of low-energy district heating networks with operational planning - Case study for existing buildings

Submit Your Proceedings

You can submit all your questions, opinions, suggestions and complaints using the contact form

Optimal dimensioning of low-energy district heating networks with operational planning - Case study for existing buildings

Publication Date: 28.10.2011 |   Pages: 37-46
Hakan İbrahim Tol and Svend Svendsen
Technical University of Denmark, DK-2800, Denmark

DOI: -


Low-temperature operation in low-energy District Heating (DH) systems is rewarding for increased exploitation of lowtemperature renewable energy sources, heightened efficiency at heat extraction, and intensified energy efficiency at heat distribution. Success of heat delivery in low-temperature operation such as 55 °C in terms of supply and 25 °C in terms of return was achieved through real cases located at Lystrup in Denmark, and “Greenwatt Way” project located at Scotland in UK as demonstration of low-energy DH systems being considered to supply heat to new houses with low-energy class. In our former study the performance of in-house heating systems was investigated for changing levels of supply temperature with consideration given both to current high-heat demand and future low-heat demand value of an existing settlement. The over-dimensions obtained at in-house heating systems originally in design stage resulted in satisfaction of heat demand of the house in low temperature operation. In this paper the operational planning of the low-energy DH systems was investigated to reduce the dimensions of the distribution network with consideration given both to current high-heat and future low-heat demand situations. The operational planning was based on boosting (increasing) the supply temperature at peak-demand situations which occur rarely over a year period. Hence optimal pipe dimensions of low-energy DH systems were investigated based on the dynamic response of in-house heating systems with changing supply temperatures ranging between 55 – 95 °C. The boosting level of supply temperature was considered to be determined separately for current high and future low heat demand scenarios. As a conclusion it was found that 40% reduction in the pipe investment cost could be reached by use of operational planning in comparison to DH network dimensioned according to high heat demand situation.


low-temperature district heating


  • Benonysson, A., Bøhm, B., and Ravn, H. F. 1995. Operational optimization in a district heating system. Energy Conversion and Management, 36(5):297-314.
  • Christiansen, C. H., Paulsen, O., Bøhm, B., Thorsen, J. E., Ting Larsen, C., Jepsen, B. K., et al. 2009. Development and demonstration of low-energy district heating for low-energy buildings. Main report and appendices [in Danish]. Teknologisk Institut Report.
  • Coskun, C., Oktay, Z. and Dincer, I. 2009. New energy and exergy parameters for geothermal district heating systems. Applied Thermal Engineering. 29(11-12):2235-2242.
  • Coskun, C., Oktay, Z. and Dincer, I. 2011. Investigation of some renewable energy and exergy parameters for two Geothermal District Heating Systems. International Journal of Exergy. 8(1):1-15.
  • Gustafsson, J., Delsing, J., and van Deventer, J. 2010. Improved district heating substation efficiency with a new control strategy. Applied Energy. 87(6):1996-2004.
  • Kristjansson, H. 2009. District heating is tomorrow's heat market. EuroHeat&Power. 6:38-42.
  • Logstor calculator 2.1. Accessed on March 2012.
  • Lund, H., Möller, B., Mathiesen, B. V., and Dyrelund, A. (2010). The role of district heating in future renewable energy systems. Energy. 35(3):1381-1390.
  • Lund, H. 2010. Renewable energy systems: The choice and modeling of 100% renewable solutions. USA Academic Press, Elsevier.
  • Madsen, H., Sejling, K., Søgaard, H. T., and Palsson, O. P. (1994). On flow and supply temperature control in district heating systems. Heat Recovery Systems and CHP. 14(6):613-620.
  • Microsoft Support. About statistical analyses tools. Accessed on April 2012.
  • Oktay, Z., Coskun, C., and Dincer, I. 2008. Energetic and exergetic performance investigation of the Bigadic Geothermal District Heating System in Turkey, Energy and Buildings. 40(5):702-709.
  • Oktay, Z. and Dincer, I. 2009. Exergoeconomic analysis of the Gonen geothermal district heating system for buildings. Energy and Buildings. 41(2):154-163.
  • Olsen, P. K., Lambertsen, H., Hummelshøj, R., Bøhm, B., Christiansen, C. H., Svendsen, S., et al. 2008. A new low-temperature district heating system for low-energy buildings. In The 11th International Symposium on district heating and cooling. Aug 31-Sep 2, Reykjavik, Iceland.
  • Paulsen, O., Fan, J., Furbo, S., and Thorsen, J. E. 2008. Consumer unit for low energy district heating net. In The 11th International Symposium on district heating and cooling. Aug 31-Sep 2, Reykjavik, Iceland.
  • Phetteplace, G. 1995. Optimal design of piping systems for district heating. CRREL Report.
  • Sanks, R. L. 1998. Pumping station design. United States of America: Elsevier Gulf.
  • Serhan, K. 2007. The thermal effects of some control logics used in GDHS. Applied Thermal Engineering. 27(8-9):1495-1500.
  • Steer, K. C. B., Wirth, A., and Halgamuge, S. K. 2011. Control period selection for improved operating performance in district heating networks. Energy and Buildings. 43(2-3):605-613.
  • Thorsen, J. E., Christiansen, C. H. 2011. Experiences on low-temperature district heating in Lystrup - Denmark. In International conference on district energy. March 20-22. Portorož, Slovenia.
  • Tol, H. İ., and Svendsen, S. 2011a. Design of low-energy district heating system for a settlement with lowenergy buildings. In 3rd international symposium on environmental management. Oct. 26-28. Zagreb, Croatia.
  • Tol, H. İ., and Svendsen, S. 2011b. Improving the dimensioning of piping networks and network layouts in low-energy district heating systems connected to low-energy buildings: A case study in Roskilde, Denmark. Energy, 38(1):276-290.
  • Tol, H. İ., and Svendsen, S. 2011c. D Determination of Optimum Network Layout for Low-Energy District Heating Systems with Different Substation Types. In the third international renewable energy congress. Dec. 20-22. Hammamet, Tunisia.
  • Tol, H. İ., and Svendsen, S. 2012. Operational planning of low-energy district heating systems connected to in-house heating systems equipped at existing buildings. In International conference on renewable energy: generation and applications. March 4-7. Al-Ain, United Arab Emirates.
  • Vestergaard, J. B. 2010. The distribution network (August). Lecture note presented at summer school district energy, Århus, Denmark.
  • Winter, W., Haslauer, T., and Obernberger, I. 2001. Simultaneity surveys in district heating networks: Results and project experience [Untersuchungen zur gleich-zeitigkeit in nahwärmenetzen: Ergebnisse und projekterfahrungen] [in German]. Euroheat&Power, 30:42-47.
  • Christiansen CH, Worm J, Jørgensen H, Thorsen JE, Bennetsen J, Larsen CT, et al. 2011. Demonstration of low energy district heating system for low energy building in Ringgårdens Afd. 34 in Lystrup [in Danish]. Teknologisk Institut Report.


Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, proceedings citation and DOI.
Open Access
Citation Download
  • 22 Total Downloads
  • 1507 Total Scanning
Share this article