GEOFIT - Ground source heat pump systems for energy efficient building retrofitting

Activity: Talk or presentation / LecturePresentation at a scientific conference / workshop


In Europe, the building sector is responsible for 40% of the total energy consumption and represents about a third of Europe´s CO2 emissions. This is a huge socioeconomic and environmental problem, more if we consider that almost half of the EU buildings have boilers installed before 1992, with an efficiency rate of below 60%. Although energy renovation of existing buildings could help to achieve the EU climate and energy targets, the refurbishment rate is currently below 1% and renewables are not widely used in the building sector. Within the H2020 project GEOFIT, easy-to-install, economical and enhanced geothermal systems for energy efficient build-ing retrofitting are going to be implemented and demonstrated at five dedicated pilot sites across Europe - a historical building (ITA), a school (ESP), an indoor swimming pool (IRL), an office building (FRA) and a single-family house (IRL). The integration of ground systems with heating/cooling solutions and heat pumps to achieve maximum perfor-mance is a great challenge that demands a solution. In order to find the best solution for each pilot site with respect to increased supply temperatures compared to a new building, different heat pump configurations are analyzed. As working fluid, a Low Global Warming Potential (GWP) refrigerant (e.g. R1234ze(E)) with a GWP smaller than 10 will be used. The system will include alternative cost-effective heat exchangers to be used with the Low GWP refrigerant like plate heat exchangers made of Aluminum instead of Copper. One favorable heat pump configuration is a twin-cycle system which basically consists of two heat pumps with different condensa-tion temperatures but with the same temperature on the source side. Alternatively, a single-stage configuration which uses a significantly larger condenser for enhanced subcooling is also analyzed. Both systems allow a more efficient operation compared to state-of-the-art heat pump systems in the case of building retrofitting. So far, no residential ground source heat pump system exists where these technologies (Low GWP, Aluminum heat ex-changers) were combined. At the end of the demonstration phase in the GEOFIT project, the action will increase the commercial attractiveness of geothermal energy in combination with ground source heat pumps and there-fore increase the penetration of this renewable source in building retrofitting.
Period22 Oct 201923 Oct 2019
Event titleEuropean Heat Pump Summit 2019
Event typeOther
Degree of RecognitionInternational

Research Field

  • Efficiency in Industrial Processes and Systems