Title: Erdwärmepumpen für die energieeffiziente Gebäudesanierung
Authors: Michael Lauermann (*1), Johann Emhofer (*1), Edith Haslinger (*1), Karl Ochsner (*2)
*1: AIT Austrian Institute of Technology GmbH, Center for Energy,
*2: Ochsner Wärmepumpen GmbH
Summary: The integration of geothermal systems for heating / cooling solutions in conjunction with heat pump technology is a major challenge, particularly in the case of renovation. In order to find the best solution for the increased flow temperatures compared to a new building for the renovation, various heat pump configurations are evaluated according to energy and economic criteria. A refrigerant with low greenhouse gas potential (GWP) is used as the working medium, e.g. R1234ze (E)) less than 10 used. A favorable refrigeration circuit configuration for high flow temperatures is a twin-circuit system, which essentially consists of two heat pumps with different condensing temperatures and the same evaporation temperatures. An alternative to this is a single-stage configuration with a significantly larger condenser for improved supercooling. Both systems should enable efficient operation when renovating buildings.