Concept of a Geothermal Extended Reach Well in Munich

In order to maximize the potential of deep geothermal energy in Munich, while at the same time reducing the number of drilling sites, development costs and the implementation time of geothermal projects, it is important that individual well sites achieve the highest possible production rates. One evident strategy to enhance the productivity of a drilling site is to expand the development radius around the location as well as the number of boreholes. Wells in the Munich area have been drilled up to 3,000 m horizontal departure (HD), but there is potential for further horizontal reach. However, this requires the outer wells to be drilled at a considerable distance, almost horizontally, from the surface starting point to the landing point. This increasing horizontal distance of the target from the well site inevitably leads to increased technical effort, cost and risk. This paper presents the challenges and limitations arising when applying conventional drilling and liner running methods on wells with extended reach. A thorough risk analysis is provided, detailing the identified limitations. Additionally, various aspects of the well design are highlighted and reviewed.