DESIGN AND PERFORMANCE OF BOREHOLE HEAT EXCHANGER / HEAT PUMP SYSTEMS

The ubiquitous shallow geothermal resources can feasibly be utilized by borehole heat exchanger (BHE) / heat pump (HP) systems. BHEs can be installed in nearly all kinds of geologic material. Design and installation must consider numerous influence factors. It is shown how the sizing needs to be done, at the example of Switzerland. Also the economic advantages of such systems are demonstrated. Finally, the basic questions of long-term operation are addressed, for a single BHE, by a combined experimental and theoretical (=numerical modelling) approach. It turns out that BHE/HP systems operate, if properly designed, fully reliable on the long term.