Lower Saxony maps reveal untapped deep geothermal energy potential beneath ancient rock

Deep geothermal energy is gaining momentum in Lower Saxony as a key part of the region’s energy transition. A new map series, published by the Lower Saxony Geothermal Service (NGD), now highlights the most promising areas for extraction. The data aims to help municipalities, utilities, and industries tap into this underused resource. The maps focus on ancient rock layers from the Keuper-era Exter Formation, which are over 200 million years old. These layers contain water-permeable sandstones that can hold thermal water at temperatures above 100 degrees Celsius, found at depths of up to 2,600 metres.

Deep geothermal systems work by extracting hot water through boreholes and reinjecting it after capturing the heat. This process supplies district heating or large-scale consumers with renewable energy. Most of Germany’s existing geothermal wells already reach depths between 2,000 and 3,500 metres. The NGD analysed data from over 1,100 deep boreholes across Lower Saxony to create the series. While North Germany has significant untapped potential, high drilling costs and exploration risks have so far limited development. The new maps aim to reduce uncertainty by pinpointing the best sites for future projects. Interest in deep geothermal energy is growing rapidly among local councils, energy providers, and industries. The maps are now available online, with further details provided on the LBEG website.

The publication of these maps provides a clearer path for expanding deep geothermal energy in Lower Saxony. By identifying viable locations, the NGD hopes to lower barriers and accelerate investment. This could make geothermal a central part of the region’s shift toward sustainable heating and power.