A Method to Analyze the Performance of Geocooling Systems with Borehole Heat Exchangers. Results in a Monitored Residential Building in Southern Alps

Geothermal heat is an increasingly adopted source for satisfying all thermal purposes in buildings by reversible pumps (HP). However, residential located moderate climates, geocooling, that implies the use of geothermal cooling without operation HP, efficient alternative space not yet explored enough. Geocooling allows two main benefits: to cool high energy efficiencies improving summer comfort; recharge ground if heating provided HP exploiting (GSHP). In these cases, geocooling avoid decreasing performances GSHP over years. To explore issues, a method has been developed and tested on real case: new building Lugano (southern Switzerland) coupled with 13 borehole exchangers. The system provides winter geocooling. During 40 months monitoring campaign, data such as temperatures, flows electricity consumptions were recorded calibrate model verify benefits configuration. Focusing operation, efficiency system, after improvements implemented, above 30, confirming, at least similar contexts, feasibility Achieved results knowledge future installations, underlining replication potential possible limits.