For four years, a consortium of research and industry has been pushing the development of so-called "Advanced Geothermal Systems". These promise to make the Swiss energy system more independent, sustainable and resilient. The basis is a new drilling technology using high-voltage pulses. This drilling technology is at the heart of the Innosuisse flagship project "AEGIS-CH", in which the Amberg Group is involved.
When the term geothermal energy is mentioned, voices are usually raised quickly about high drilling costs and man-made earthquakes. Thanks to the Innosuisse project "AEGIS-CH", this could be history in the near future.
For the project led by ETH Zurich, a comprehensive analysis includes the Swiss energy system, considering a new generation of small geothermal power plants. Together with the Paul Scherrer Institute, the University of Applied Sciences OST, and the industrial partners SwissGeoPower, Amberg Group, Basler & Hofmann, Kibag/Geotherm and Sika, the so-called "Advanced Geothermal Systems", or AGS for short, are being advanced.
The Amberg Group is contributing its expertise in geotechnical engineering and underground construction to the project and is driving the further development and marketing of AGS technology through SwissGeoPower.
Simplified, AGS can be thought of as a giant geothermal probe. Two boreholes up to 10 kilometers deep are connected by several cross-connections. Together they form a closed circuit in which CO² circulates as a heat transport medium. An AGS can produce an electrical output of about 1MW or a thermal output of about 10MW.
A new drilling technology called "Plasma Pulse Geo Drilling" makes AGS possible. This uses high-voltage pulses to blast open the rock at depth by forming a plasma. The new drilling method solves two problems of the previous fracking technology: On the one hand, it is much cheaper, since the massive effort for replacing the drill heads at depth is eliminated and only tensile stresses have to be overcome. Secondly, there is no danger of vibrations or even earthquakes with this technology.
The consortium is convinced that the new "Advanced Geothermal Systems" can significantly help to reduce energy imports and cushion the fluctuating solar and wind energy.