Heating and Cooling with Renewable Energy from Wastewater

A Large-Scale Case Study from Vienna


  • Flora Prenner Rabmer GreenTech GmbH
  • Rainer Wiedemann Rabmer GreenTech GmbH




Energy from Wastewater, Decarbonization, Building Sector, Heating and Cooling, Monitoring


Energy from wastewater is recognized as a renewable energy source and can add a valuable contribution to the EU’s path to decarbonization. With modern heat exchangers and heat pumps, buildings and districts can be supplied with energy for heating, cooling and water heating. Based on the successful results of the implementation in Vienna Blumental, another project in Vienna has been rolled out: The Vio Plaza building complex will be supplied with energy from wastewater for heating (1.2 MW) and cooling (6 MW). This article presents the case study at Vio Plaza, gives a detail description of the system design and delivers first-hand information about operation of the installed system. Special focus is put on the innovative monitoring system and resulting monitoring data, which prove the good operation of the system. Based on these results, further knowledge about these systems will be gained to support the increasing implementation of this technology.


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How to Cite

Prenner, F., & Wiedemann, R. (2024). Heating and Cooling with Renewable Energy from Wastewater: A Large-Scale Case Study from Vienna. International Sustainable Energy Conference - Proceedings, 1. https://doi.org/10.52825/isec.v1i.1230

Conference Proceedings Volume


Solutions for Energy Efficiency