For the "Greenbrothers" in Zevenbergen in the Netherlands, everything revolves around ideal conditions for growing eggplants. Heating should be as climate-friendly as possible, preferably with renewable geothermal energy. The concept is very simple: a well raises the warm water from a depth of 1,535 meters. Then, after the heat has been extracted, the cold water is pumped back down a second well into the reservoir.
A Herrenknecht Slant Directional Drilling Rig (SDD) was used for both boreholes. With entry angles between 8° and 90°, the SDD drilling method combines the strengths of horizontal and vertical drilling technology to safely and efficiently tap near-surface energy sources up to a maximum depth of 2,000 meters. Drilling of the two boreholes in Zevenbergen, at angles of 90° and 68° and depths of 818 and 840 meters respectively, began in October 2017. In February 2018 the work was successfully completed. With a capacity of 6-15 megawatts, since commissioning the environmentally friendly geothermal plant has reduced the ecological footprint of the greenhouses significantly.