IEA HPT Annex 52, Long-term performance measurement of GSHP systems serving commercial, institutional and multi-family buildings, started in January 2018 and will close in December 2021. Within the annex, a large number of larger ground source heat pump (GSHP) systems in seven countries are monitored and analyzed from a long-term performance perspective. By the end of 2019, 40 GSHP performance-monitoring case studies, located in Sweden, the Netherlands, the UK, Finland, Germany, Norway and the USA, form part of the Annex 52 work. These case studies cover a range of building types, system applications and ground sources. Annex 52 offers unique experience and information on GSHP system performance, which will result in guidance on instrumentation, monitoring, uncertainty analysis, data analytics, performance analysis and suitable performance indices based on international experience. This paper gives an overview of Annex 52, including the active monitoring projects and the work and findings so far.Peer reviewedMechanical and Aerospace Engineerin
