Lower Saxony's deep geothermal maps reveal untapped clean energy potential

Deep geothermal energy is gaining momentum in Lower Saxony as towns, utilities, and heavy energy users seek cleaner heating solutions. The technology taps into hot water from deep underground rock layers to supply district heating networks and large consumers. Now, a new set of maps aims to unlock more of this potential across the region. The Lower Saxony Geothermal Service (NGD), part of the State Office for Mining, Energy, and Geology (LBEG), has released a detailed map series to support geothermal development. These maps focus on the Exter Formation, a Keuper-era rock layer over 200 million years old. Found at depths up to 2,600 meters, this formation holds water hotter than 100 degrees Celsius—ideal for energy extraction.

To create the maps, LBEG experts analysed data from more than 1,100 deep boreholes. The results pinpoint areas in Lower Saxony where conditions are best suited for drilling. Most of Germany’s existing geothermal wells already reach depths between 2,000 and 3,500 meters, proving the technology’s feasibility. Despite its promise, deep geothermal energy remains underused in northern Germany. High drilling costs and the risks of exploration have slowed progress. Yet with growing demand from municipalities and industries, the sector is poised for expansion.

The new maps provide a clearer picture of where geothermal energy can be most effectively harnessed in Lower Saxony. By reducing uncertainty for developers, they could help accelerate projects and cut heating emissions. The region’s push for geothermal aligns with broader efforts to make deep underground heat a cornerstone of Germany’s energy transition.