Project Deep Heat Mining Basel
Harvesting geothermal energy outside volcanic areas
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Enhanced geothermal systems (EGS), also known as Hot-Dry-Rock (HDR) or Hot-Fractured-Rock (HFR) systems, enable the exploration of the Earth's interior heat outside known geothermal provinces. In contrast to a geothermal field in one of these volcanic/tectonic anomalies, an EGS depends on the artificial stimulation of otherwise tight formations. Fluid will be circulated in a closed circuit mode, whereby reservoir pressures and fluid throughputs are managed by balanced production and injection rates in multiple well array.
In Basel/Switzerland a pilot plant is being developed to use energy won by EGS technology for co-generation of electrical power and heating energy. The aim is to develop the first co-generation power plant from an enhanced geothermal reservoir with a power production of 3 MWe and a heat production of 20 MWe for the local district heating grid.
A first reconnaissance well was successfully drilled in 2001 to a depth of 2755 m. The first exploration well to the target depth of 5009 m was successfully completed in October 2006.
The hydraulic injections to create permeability in the crystalline basement rock produced a seismic event of magnitude 3.4 and shocked the urban population. According to a pre-defined alarm system, the operation was immediately suspended. An independent risk analysis has been initiated to investigate the risks of further operations.
The entire injection process and the related seismic activity is very well documented by a previously installed monitoring network. These records are a unique data set that will provide vital information for future EGS developments.
The client Geopower Basel AG ordered Geothermal Explorers LTD to investigate the events and further develop the technology to exclude induced seismicity of unacceptable magnitudes.
Geothermal Explorers Ltd. ist responsible for the project development and project management. Geopower Basel AG is a consortium with the following partners:
