Drilling and installing geothermal probes is a challenge. We were in the field, interviewed and observed experts. For heavy equipment, the space conditions between existing buildings are often cramped and accessibility is limited. And you are immediately exposed to the elements — the workplace is cold, wet and dirty. We found the greatest potential in the preparation, insertion and unwinding of the probes. After an extensive analysis of the competitor's products and the manufacturing capabilities of our client, we carried out studies on various pipe arrangements, winding and insertion methods and the reduction of bore diameters. Welding variants to reduce diameter and increase strength have been developed. We tested different probe foot geometries and corresponding manufacturing concepts with CFD flow simulations in order to optimize the hydraulic resistance.

The new geotwin takes its name from the patented double tube winding developed in this project. The reel assembly is simplified and unwinding is improved. The slender, robustly welded probe foot has an optimised hydraulic system and, thanks to its split with intermediate channels, displaces the water in the borehole effortlessly.