A design originally based on a 10.6 kW heat output heat pump and two conventional 32 mm diameter double-u heat loops each 125 m long was proposed for a detached house in Schellenberg, Liechtenstein. From the results of thermal simulations, the designers proved that by using JANSEN power wave single-u ground source heat loops, a borehole length of 100 m each was more than adequate, which represented a 20% reduction. Temperature monitoring began from the time the system went into operation at the end of 2015. According to meteorological records, January 2017 was the coldest month for 30 years. However, the measured brine temperatures at the heat pump never fell below +4° C. Another example project in Mannheim shows just how well near-surface soils can perform as an energy source.
Strict borehole depth restrictions applied to a ground source heat pump system for a two-storey end terrace house (newbuild). A 6.1 kW heat output heat pump extracts a nominal 4.8 kW of heat energy from the ground below. A conventional design would have required a borehole depth of 140 m. However, a depth restriction of barely 37 m applied to this site. It would have been illegal to drill down into groundwater resources at this location. So where would the required thermal energy come from? By using two JANSEN powerwave single-u ground source heat loops, a ground source heat pump system could be relied upon to provide heating, hot water and cooling. These projects share a single common feature: out of a situation with supposedly questionable feasibility, it was possible to design a customised ground source heat pump solution that had higher output, required less space and ran less risk of encountering problems during installation.