Biggest Geothermal Power Station in South Germany

Project Description:
The by now biggest geothermal heat and power generation plant in South Germany has been built at Unterhaching which is located south of Munich.

The implementation of the resolution of the Municipal Council to install a geothermal doublet started with the foundation of the Geothermie Unterhaching GmbH & Co KG in 2002.

Since 2007, the own heating network has been supplied reliably, and since 2009, power has been fed into the public grid.
The breakthrough for geothermal energy use in the Bavarian Molasse Basin was achieved thanks to the successful development of the Malm aquifer by means of two deep wells which surpassed all expectations at that time. Thus, the Unterhaching geothermal undertaking became known as a beacon project far beyond the Federal State‘s borders, continuing to set standards in the field of deep geothermal energy use via constant innovations (e.g., production technologies).

Still today, Geothermie Unterhaching GmbH & Co KG is a 100 % subsidiary of the Unterhaching Municipality. Meanwhile, the provided heating capacity amounts to the consumption of 5,000 households.

Facts and Figures:

• Drilling-engineering design, geological planning, and supervision of the drilling and completion of the deep wells
• Planning, supervision, and evaluation of the hydraulic tests and trial run
• Licensing procedures under the Mining Code and the Water Act
• Design and commissioning of the thermal water loop incl. dimensioning of the submersible pump, design and supervision of the initial installation
• Planning, supervision and documentation of pump replacements and acidizing
• Geochemical and process data monitoring, technical consultancy services to the operator

Facts and Figures:

• Wells: 3,325 and 3,413 mTVD
• Length of thermal water pipeline: 3.6 km
• Production temperature: 122 °C
• Production flow rate: 150 l/s
• Output, thermal: max. 38 MW
• Output, electric: max. 3.36 MW
• Avoided CO2 emission in 2010: 31,781 t